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0:38

Today we are honored to welcome Dr. Brian Smiley for

0:41

a lecture on pulmonary Adeno. Adenocarcinoma atypical

0:44

pulmonary cyst and lung RADS.

0:48

Dr. Smiley completed his medical school at Wayne State University School

0:51

of Medicine and continued with residency as part

0:54

of the Detroit Medical Center WSU and Diagnostic

0:57

Imaging. He then trained at the

1:00

University of Michigan for a cardiothoracic Imaging Fellowship after

1:03

almost six years in private practice. He then joined

1:06

the faculty at UMass Memorial health system and Chan medical

1:09

school as assistant professor in the cardiothoracic division.

1:13

At the end of the lecture, please join Dr. Smiling a

1:16

Q&A session where he will address questions you may have on today's

1:19

topic.

1:20

Please remember to use a Q&A feature to submit your questions so

1:23

we can get to as many before our time is up with that.

1:26

We're ready to begin. Today's lecture Dr. Smiley. Please

1:29

take it from here.

1:31

Thank you for the kind introduction.

1:34

So as we as said we're gonna talk about pulmonary. I

1:37

know carcinoma atypical pulmonary cysts and get

1:40

into a little bit of lung rats. Now while any

1:43

of these topics could be quite interesting

1:47

on their own. I think it'll be good to look at them together. I

1:50

have no disclosures. So the way I'd like to to frame

1:53

this whole talk is that each one of

1:56

these has a lot that we can get into but I think

1:59

it's important to take a step back sometimes and

2:02

look at how these all are related and I

2:05

think that'll be a little more apparent once we

2:08

get into some of the details, but essentially it'll be a

2:11

little refresher on how many I know carcinoma get into a

2:14

little bit of atypical pulmonary cyst which then Segways to

2:17

some of the updates on the new version

2:20

of lung RADS which came out in late 2022. So I

2:23

think the way to look at them as

2:26

not separate any of these but they're all going to be related but then we'll

2:29

bolster that with a few cases which will kind of

2:32

bring it all together.

2:33

So I don't want to miss any time we

2:36

talk about lung cancer. I think it's very important to always

2:39

understand its place in the in

2:42

the world of cancer. So these are some of the most recent estimates

2:45

from the American Cancer Society and for the

2:49

2023 estimates and I think it's always important to note that

2:52

lung cancer is very high up there. It's the number

2:55

two new cancer diagnosis for both males and

2:58

females and then also it's by Far and

3:01

Away the highest cause of death. So that's always

3:04

something that hasn't really gone away in a while. So it's definitely

3:07

fruit for us to

3:10

make a lot of progress on so it's by far

3:13

the the most common cause of cancer death and like I said and

3:16

then the second most cancer diagnosis so all of the

3:19

all the cancer deaths in 2020, I think this is

3:22

very notable as well one cancer was much

3:25

more than breast prostate and colorectal

3:28

cancer is combined. So we have a lot of work to do

3:31

and I think that hopefully

3:33

this will help give you a different perspective on it.

3:37

So as a refresher, there are a few

3:40

lung cancer types and it's broken down into non-small cell

3:43

lung cancer and small cell lung cancer

3:46

of the of the non-small cell.

3:49

We break it down further into adenocarcinoma squamous cell

3:52

carcinoma and large cell carcinoma small cells a

3:55

little less interesting and mostly small cell and then

3:58

a combined small cell.

3:59

But to go into pulmonary to

4:02

carcinoma why we would do this of 81% of the

4:05

non-small cell lung cancers are of lung cancers

4:08

are non-small cell and then of that group over about

4:11

62% of the latest data shows

4:14

that those are adenocarcinoma. So we had to pick one thing

4:17

to attack. This would be one so getting into

4:20

the details is not important again, but knowing that it's the most common

4:23

lung cancer subtype is important and it has

4:26

been increasing prevalence. This will go back to

4:29

the the updated classification from 2014. But

4:32

we all should know that smoking is the most important factor

4:35

and a little bit of the presentation usually

4:38

cough dissemia chest pain then of

4:41

Hope unfortunately, hopefully if we don't see you homop just

4:44

this horse and weight loss. Those are a little more worrisome features.

4:48

So to just refresh the whole, you know,

4:51

it's to go into each little detail but of that pulmonary and of course

4:54

the normal classification from 2014.

4:57

I I think it's good to just to

5:00

step back and think of what the different

5:03

categories are, but then we'll look at them from a

5:06

distance and I think that'll help frame the rest of the talk as well.

5:09

So the atypical adenoma is hyperplasia the

5:12

lowest grade then adenocarcinoma and situ and then

5:15

minimally invasive adenocarcinoma and then invasive adenocarcinoma.

5:18

So one of the big differences from

5:21

the previous classification was that the lepidic predominant was

5:24

put up under the invasive side. So

5:27

if you just step back and look at it as maybe like pre-invasive lesion

5:30

that are usually very small and don't really

5:33

have any solid components to an invasive lesion

5:36

that that I think is something that we should be mindful

5:39

of but the interesting part about the typical pulmonary

5:42

cyst and some of the different ways to look at pulmonary lesions

5:45

in general I think is gonna tow this line

5:48

and it's not as simple as just pre-invasive and

5:52

invasive so just keep that in mind as we go forward.

5:55

And I think before even get into some

5:58

of the details of an atypical pulmonary cyst. It's always good to go

6:01

back to the inflation of society

6:04

glossary for terms for thoracic Imaging because knowing what

6:07

a cyst is is always going to be helpful when we

6:10

get into the more complicated ones. So this was the the main

6:13

the last version of the glossary from 2008

6:16

and what is described

6:19

as a a cyst is

6:22

they gave it in pathology terms and then

6:25

in our our radiographic or the CT terminology and

6:28

I think it's interesting to point out the we have a

6:31

thin wall cyst here and probably the most important part that will come into

6:34

play later is that assist was defined as

6:37

having a wall and usually a visible wall that we could see

6:40

on our Imaging studies but often less than two millimeters

6:43

thick. So that's something that will bring up

6:46

a little bit later when I bring come into the lung RADS, but

6:49

it's always good to keep this in mind as we move forward

6:52

to a little more in depth. So this is

6:55

A radiographics article for Cole from 2018 and

6:58

this was going into the topic of

7:01

lung Cancer's associated with cystic spaces and

7:04

pointing out that it's or an unorganized features

7:07

that you know, all these different unrecognized features of early disease. And

7:10

in the article they do they do

7:13

bring up the several examples of

7:16

cases that show how our low-grade pulmonary and

7:19

no carcinoma are pre-invasive lesion could progress to

7:22

an invasive lesion, but what I think they do a really

7:25

good job as they take a lot of the the more the

7:28

more recent and in the past studies that

7:31

were done looking at lung cancer is that were associated

7:34

with cystic spaces or just CIS in

7:37

general so they took a lot of those and I think it's good to

7:40

look at this this table so note that

7:43

most of these studies had anywhere from 15 to

7:46

30 patients when they were looking at Perry's sister's

7:49

and the main thing to take note of is

7:52

that I know carcinoma was by far the highest

7:55

energy that was found on pathology. So

7:58

of these cases they're anywhere from two thirds. So up

8:01

to 90% of the cases. They

8:04

looked at with the assists were adenocarcinoma. So that's another

8:07

reason why it's important to look at

8:10

them like this.

8:11

But you know, that's the this was

8:14

even discussed as far back as the 1940s. So

8:17

this is by no means something new but some of the big things

8:20

in the article that I really liked was the it

8:23

got into the the nomenclature and it's it's important to

8:26

note that this is 2018. So at the

8:29

time, you know, the the terminology wasn't really well

8:32

defined or is definitely not the newest lung RADS. So

8:35

they came to the conclusion. They were going to use cancers associated

8:38

with cystic spaces and this nomenclature really

8:41

again wasn't very defined it kind of fell under this

8:44

little broader term of cystic airspace

8:47

and that again goes back a little bit to the even farther

8:50

back to the inflation or Society glassery. But

8:53

what they did point out is the importance of identifying the

8:56

relationship of lung Cancer's and

8:59

the cystic spaces. So that's kind

9:02

of what we're gonna get into a little bit as well. And I

9:05

think it's important to just be mindful of because it's not just

9:08

as simple as our speculated nodule or does it have

9:11

suspicious features anymore so we can go a little further and

9:14

it did point out that there is a quite a little

9:17

bit of limitation in the debt the actual data at the how

9:20

many of these cancers we missed and some of that was looked

9:23

into even as with the Nelson trial there was

9:26

looking at what type of cancers were missed most often, but

9:29

this is definitely something these type of lesions in the lungs are

9:32

are much higher risk for delaying the diagnosis because

9:35

of these features.

9:37

And these these more subtleties that don't fully fit

9:40

into those prior categories.

9:43

So I think I definitely want to bring up this is this is a great resource.

9:46

So when we're looking at maybe the lung

9:49

RADS and all from from the ACR, we have a lot of resources and

9:52

I highly suggest everyone to check out this lecture

9:55

by Dr. Jared Christensen who's the chair of the Sarah

9:58

long rides committee. This was going into

10:01

more specifically the exact long RADS

10:04

like table that points out each little

10:07

Nuance of the not only the

10:10

newer features of the categories, but also like more

10:13

specific examples, I'll give some and do something similar but

10:16

again stepping back and looking at it in

10:19

a different perspective, but I highly suggest it's a really short talk. There's

10:22

links directly to the YouTube clip of

10:25

it and I even saw it at our last side of thoracic Radiology

10:28

meeting not too long ago.

10:31

But this is how I would like you to approach this

10:34

so back back with either the and

10:37

just even an incidental pulmonary nodule of

10:40

the fleischner guidelines or with lung RADS.

10:43

This is something just I even noticed in the

10:46

experience of working in the real world. I think it's not

10:49

as simple as just a nodule or the

10:52

sub solid nodule or putting it into these smaller buckets. I

10:55

think it's always good to take a step back and look at it as

10:58

each each of these quote lesions in the

11:01

long could have different features.

11:03

So if you really try to break it down into the most like obvious different

11:06

features, if you think of them as solid

11:09

and then ground glass components and then

11:12

cystic components, that's probably a good way to

11:15

look at as the building blocks for what these lesions can

11:18

look like or how they may progress. So if

11:21

you have only

11:23

if you have only one type of one of these components you

11:26

can consider that a relatively simple

11:29

lesion, but when you have more than one of

11:32

these components or potentially all three, it's it's

11:35

essentially a more complex lesion. So if instead of

11:38

having just a binary solid or non-solid,

11:41

I think looking at it as a simple and complex

11:44

and knowing that there's a lot of nuance in there that allows

11:47

you to be able to like apply these different components

11:50

to one of these lesions.

11:53

So it's always fun too to have a patient

11:56

that may have all of these lesions on in their

11:59

in their case, but also even on the same slide, so

12:02

it's also it's also fun to even have on the same image, but it's

12:05

also a good to be mindful of maybe a lesion

12:08

that has all of these features in one spot. So sometimes there's

12:11

gonna be lesions that are a little harder to characterize not just

12:14

on one image but might take a different look in

12:17

a coronal or sagittal plane to really appreciate all the components

12:20

of it when they are so complex.

12:23

so

12:24

One of the other fun things I wanted to bring up that came

12:27

up. So there was an article that looked into

12:30

looking at minimum intensity projections

12:33

for looking at covid-19 patients.

12:36

And when I started a UMass

12:39

we were going to play around with some of our CT protocols. I had never

12:42

used one of these minutes before but I kind

12:45

of liked it and I noticed there was a lot of different techniques

12:48

that were used but when I looked I found

12:51

this article because we were playing around trying to create our own and

12:54

maybe make a different style. Will this article

12:57

was looking at pretty much the ground glass components and

13:00

how to better assess them and they came up

13:03

with the various techniques and we're having axial criminal

13:06

and sagittal reconstructions in this minute format, but

13:09

we ended up taking what we had previously done and just

13:12

made it a little more thin slice. So what we

13:15

had was somewhere around seven millimeter slices and it

13:18

was just a coronal minute, but we ended up playing around and trying

13:21

a few and I kind of like this there was a two millimeter by one

13:24

Are spacing minute that we did and

13:27

it really helps show these cystic lesions quite

13:30

a bit and I actually really like him we're adding it to

13:33

all of our CTS now and one little tip to take note of

13:36

from it is that when you are creating

13:39

these if you create it from an actual lung filter

13:42

that has that higher resolution the space resolution it ends

13:45

up being noisy. So if you create it from a base

13:48

of soft tissue images the soft tissue filtered images,

13:51

it ends up being a little clearer and it

13:54

shows up quite beautifully actually and it's it's

13:57

simple just a typical Long window as displayed in

14:00

the packs, but I'll show you a few examples. It really

14:03

shows the way that these lesions can pop

14:06

out and this is a good one in particular which I'll

14:09

show a little bit later that there's definitely the solid component but the

14:12

cystic components are hard to associate if you don't catch them

14:15

in the exact right plane, and it's also very good

14:18

for showing emphysema. So emphysema really

14:21

pops on this and shows you

14:24

extent of it and sometimes the really really microscopic emphysema.

14:27

That's that barely visible. It'll really show

14:30

up on here a little bit more so you don't necessarily want to overcall but

14:33

if you're over on the fence this this is the sequence really helps.

14:36

So now moving forward to with

14:39

lung screening. I think we all

14:42

understand that the the major goal of of

14:45

lung screening is to find some of these really

14:48

low grade lesions and catch them when they start

14:51

to be slightly more high-grade, but definitely before they become

14:54

invasive so this would be like our typical

14:57

scenario that we would want to want to catch

15:00

a lung cancer patient because we want to avoid cases

15:03

like this because this is much different prognosis

15:06

for the patient and you know, so

15:09

catching these lesions early would be very helpful and

15:12

we definitely don't want to lead into something like this.

15:15

So these are the type of things. We're hoping to avoid by

15:18

catching these things early.

15:21

So which brings us to lungs the new version in 2022?

15:25

So overall there's a significantly expanded

15:28

note section and the major

15:31

addition of the pulmonary cyst is how I'll tile of this

15:34

together one of the other some of the other major features that I

15:37

like to point out are the progression that previously

15:40

when you had a category 4A and when

15:43

the there was a three-month follow-up or even on the

15:46

pet there was usually just only the option to either an act

15:49

on it or go back to a category 2, but if these

15:52

cases are stable and these lesions are stable or decreased be

15:55

able to go to a category 3 and get that six month

15:58

follow up rather than jump all the way to 12 and then

16:01

there's the removal of the percentage for the risk of pregnancy

16:04

in each category. So we found that's a little not as accurate

16:07

and made things a little confusing and

16:10

then the other interesting one that I particularly like

16:13

was the complete change of when you have a

16:16

suspicious findings of inflammatory or

16:19

infectious process instead of labeling into four

16:22

B to do these short-term follow up it's labeled.

16:25

Back as the category 0 which would determinology of

16:28

incomplete may not be you know, exactly but

16:31

I think it expands on that previous where you

16:34

just had partial images or something that couldn't be read

16:37

on its own. I think I like that allows that without giving

16:40

it this like really high number and suspicion. So

16:43

overall as you can see just from afar the

16:46

the actual document is quite more extensive than I was

16:49

in the past, but with particularly notes of

16:52

the the notes section and all the things we get into so I'll pull

16:55

up the most important to

16:58

this talk new part is the atypical pulmonary 6

17:01

sis section in the middle of the notes,

17:04

so

17:05

Overall, it kind of reminds us of that thinwald

17:08

cyst being the simple cyst

17:11

with less than two millimeter wall, but then

17:14

also goes into this the slightly more complicated lesions

17:17

and gives you a little bit more detail to remind

17:20

you about what these things can these lesions come

17:23

look like and then towards the very end. It also gets into

17:26

some of the more Nuance like conductor Christensen lecture. He'll

17:29

go into each one of these very well and show you some of

17:32

these different conundrums it brings up but also it

17:35

reminds us that in with the

17:38

link at the bottom to a link to more of

17:41

like a diffuse cystic lung disease, which we definitely have

17:44

to be mindful of especially in these settings of

17:48

When we're trying to decide whether this is

17:51

a lesion we need to act on in this in the vein

17:54

of lung cancer screen or lung screening. So what I'd

17:57

like to do here is also remind you of that so these

18:01

These lesions they could you could have

18:04

some lesions in the lung but we also have to remember that there

18:07

are these other conditions. So if

18:10

I showed you this and then said this was their their scan the

18:13

year prior you could go back and see that there's a few nodules. There's

18:16

maybe a few cystic spaces acystic areas there but we

18:19

got to be mindful of other conditions like langerhansol history.

18:22

So sometimes the cavity that can

18:25

form the can mimic cysts and it's definitely a smoking related

18:28

disease. So love of the diffuse slung diseases. I think

18:31

this would be the one to get the most familiar with so we're

18:34

not gonna go into too much detail there. But it's also just to

18:37

judge suppose with a more diffusive going disease

18:40

like bird Hog Day syndrome. So these are gonna have a lot

18:43

of thin wild cysts and they have different features, but

18:46

then all so something and I have all inflight

18:49

and traditional pneumonia and this is a patient with systemic lupus you're

18:52

mitosis and also notice they have the cardi

18:55

Maggie and some plural fusions.

18:58

But now to get into the actual details

19:01

of what these new categories have like in the actual

19:04

table and you know, I would encourage people to because

19:07

of the complexity of the table. I would never

19:10

hesitate to have this in a reading room even in subspecialty

19:13

Reading rooms that I've worked in. We've always had these

19:16

these out because it does get quite complicated and you

19:19

know, I have no intention of absolutely memorizing every

19:22

little corner and potentially for getting something.

19:25

So I always like to refer to it when I'm reading a case and there's

19:28

something I'm curious about. So I'll start kind of

19:31

from the more the more significant the the more severe

19:34

and I think it'll make sense going in this direction as to

19:37

what the changes were made.

19:39

So I'll bring your attention to the typical pulmonary

19:42

6th section here towards the end. So we left our

19:45

solid nodules in the part solid but then it really

19:48

does give you a little do you a lot more detail and bulleted

19:51

points for what the atypical pulmonary cyst it and

19:54

some of the features that we're gonna need to look for. So it brings up a thick

19:57

walled cyst and then with growing or well thickness

20:00

or nudularity. It'll have a growing multilocular

20:03

cyst and that's the overall mean diameter and

20:06

then I'm multilocular cyst with increased laculation or

20:09

new increased opacity. So we think of

20:12

that is that's that increased complexity of

20:15

lesion, which is gonna have those multiple components. So

20:18

it's not that that's probably the trickiest one to get into words, but

20:21

that's basically what it was referring to and then

20:24

for four, ah, the

20:27

atypical pulmonary cyst still comes up and

20:31

what they did here was that this is more if you have

20:34

a thick walled cyst and we're gonna still call it a

20:37

four with the three month recommendation and then a multilocular

20:40

system Baseline would fall under this category and then

20:43

a thinner thick walled cyst that becomes and

20:46

develops that multilocular character will fall

20:49

under the foray.

20:52

For three now. This is one of the things I'd like

20:55

so for three the typical pulmonary cyst will have a growing system component

20:58

and if there was already this established

21:01

cyst, but one thing I really liked was that this

21:04

is where we allowed the 4A nodule that was stable

21:07

or decreased to go to the three-month follow-up.

21:13

now the even the the zero one two

21:16

one and two categories, they are similar involved

21:19

when you look at the category 2 where it'll well the

21:22

zero like I mentioned for the one to three

21:25

month follow-up and then the category 2 which

21:28

accepts those the stability of those

21:31

categories through four and then after three and then

21:34

once you develop that stability you can go back to the two but I

21:37

really like the clarification on that. That's really helpful.

21:42

So here we have we'll go through a few cases and

21:45

if you were to get this case in the wild.

21:49

I think with a lot of these features and not necessarily

21:52

having a prior. I think it would be reasonable to

21:55

still use the Forex category on this which would

21:58

show some of these worrisome features

22:01

that we talked about and I I would say

22:04

don't hesitate in using this like you would have in the

22:07

past but I will say that once you really looked

22:10

look at a lot of these cancers and how subtly they

22:13

will develop. I was probably guilty of

22:16

this of maybe being overusing this a little bit when

22:19

I saw these really early before the long RADS was

22:22

updated and gave us the I guess the go ahead to

22:25

look at these lesions like that. So I I

22:28

think looking at more of the real complex ones and

22:31

now we have the ability to use the

22:34

other categories to characterize these lesions that maybe slow

22:37

growing or low grade, but they do usually develop into

22:40

a cancer. So that's just cautioning with that.

22:43

Now here's here's another case. So this is

22:46

the same case just add different levels. And this is always a

22:49

good way to bring up that one image

22:52

is really not gonna always show you the entirety of

22:55

Illusion. So this is just, you know, a slicer to apart

22:58

but seeing that there's a solid component that's really difficult

23:01

to measure and it's almost like a stellate but

23:04

there's definitely a solid component to it. And then when you

23:07

go a slice or so down you do see that there's a cystic

23:10

component to it. So if you had this as your case as a

23:13

baseline, you definitely want to look at another

23:16

plane. So I have one in the examples of that minute. It's

23:19

maybe the older style so it's not the super thin slice,

23:22

but it does give you an example of how these cystic portions

23:25

are related to the solid portion.

23:29

So

23:31

What would we give this? I think this you could

23:34

probably end up looking at it and oh, we have a

23:37

prior. So now looking at it in a 15 month progression that

23:40

completely changes everything because we really didn't have a good solid component

23:43

now when just looking at the case

23:46

in isolation, so seeing the 15 month progression, you can

23:49

see that there's this cystic component that is growing.

23:53

So with that in mind that would give this a category three

23:56

designation.

23:58

So here's another lesion now this lesion.

24:02

is much larger, but when you look at it, it

24:05

has multiple septations here and there

24:08

and

24:10

but there's really no solid component. So if this was your Baseline

24:13

exam

24:16

This would be a great example of what a for a for multilocular

24:19

cyst at Baseline would be.

24:22

now

24:24

Now that we have our multiple active system. Wow at

24:27

the time. There was really no good.

24:30

Recommendations for what to do? So this was just watched and

24:33

nothing really happened for two years. And now

24:36

you can see this lesion is quite a

24:39

bit bigger, but overall has essentially the same feature so

24:42

just multiloculates cyst and really

24:45

nothing in the way of a solid component

24:48

that would be actionable. So this brings up some other

24:51

conversations, too of what do you really do

24:54

with this because usually we would typically wait to

24:57

a solid component develop or something that would

25:00

potentially be positive on a PET CT but this

25:03

really would probably not be a good situation for

25:06

that. This would have a high risk for pneumothorax and

25:09

some of the surgeons probably would want to

25:12

to watch this but I would caution you

25:15

this is a good a really good example of the need for multidisciplinary discussion.

25:19

And so this being two

25:22

years later this would still fall under now

25:25

before B because you have this growing

25:28

cystic component.

25:30

Now, let's get to even more interesting looking back because if

25:33

we go farther back.

25:36

This lesion was present.

25:38

Over a nine so even nine years prior

25:41

this lesion was present and if you had this first case,

25:44

well, even those a contrast enhance if

25:47

you had a that case in the first in the current state of

25:50

lung RADS, you'd still probably give that a lock

25:53

multilocular cyst and that would have gone quite short-term

25:56

followed but as you can see the growth is overall

25:59

very slow. So not all of them are going to behave this this well

26:02

with and just grow

26:05

overall in size, but I think it does bring up the concept of

26:08

should we do something earlier because the that

26:11

current exam after the the full nine year progression

26:14

and even two years after the one lesion

26:17

You have a much broader plural attachment at this point.

26:20

So there's likely involvement of the plural and from

26:23

a surgical standpoint. This changes things quite a bit. So if we

26:26

can get these lesions a lot earlier, I think

26:29

it would be beneficial for the patient but it really

26:32

does help to look at it in these other points too because

26:35

it's quite a quite a broad attachment at this point.

26:39

So now we have a little bit more of a subtle. This

26:42

is a little more subtle lesion and going

26:45

through this.

26:47

You with just one image. It's a

26:50

little hard. There's maybe some laculate multilocular

26:53

components to this. But I guess you

26:56

could consider this a multilocular cyst with the information I gave

26:59

you and looking at in the coronal plane. There might have

27:02

been a septation down in the middle of it. But that's still gonna

27:05

fall under roughly. What I would consider a 4A

27:08

for a multilocular system Baseline, so we

27:11

didn't have a prior for this. So this is all gonna follow

27:14

the lesion through history as if we

27:17

were doing this in the current state and looking back.

27:20

So nothing was really nothing really happened on

27:23

that initial scan. And here we have a

27:26

two year progression. So after two

27:29

years from that first case, you'll see

27:32

much more laculations to it. There's definitely becoming

27:35

some more septations the assistant components are

27:38

growing. So this is something that we should be

27:41

mindful of and this is a lot harder in the

27:44

setting of a lot of advanced destructive emphysema, but

27:47

it's

27:47

to occur. So this is why looking at

27:50

these features and not turning your brain off when you have bad emphysema

27:53

is going to be very important.

27:55

So

27:57

again, this was not really in the state of the current

28:00

lung rats. So not much was done here. So

28:03

a three years so a year after that last case

28:06

and three years after that initial we have a much

28:09

larger lesion.

28:10

you have

28:12

A few solid components developing at the margin of this complex

28:15

lesion. So this should raise our

28:18

suspicion that's something else is going on. So I think

28:21

this also shows the power of the coronal

28:24

plane. So these are just regular reconstructions. They're not the

28:27

minute but the progression from that to the

28:30

second year to the third year really really shows the

28:33

amount of the solid component.

28:35

And how it's really related to the margin of the cyst and

28:38

it also shows the the complexity and the increased

28:41

laculation but but really before there wasn't

28:44

much to it. And if you were going a little fast, sometimes

28:47

it's hard to tell that Association of that solid component

28:50

with this lesion. So I think these other planes are very

28:53

very helpful and in the future, I'm sure we're gonna

28:56

be doing a lot more of a three-dimensional Imaging anyway,

28:59

so I think getting used to these multiple planes

29:02

is going to be very helpful rather than just being married to

29:05

only in axial and axial

29:08

view or something and this shows the the minute shows

29:11

really how that occulation and the cystic components can really

29:14

pop.

29:16

on that case

29:18

Now this case is one I encountered

29:21

in the real world in private practice and it's a

29:24

really interesting one because again, it's the the size of

29:27

the lesion is one thing but when you really

29:30

look at these different components and analyze it

29:33

with that kind of process of the the lens that we've been

29:36

discussing. It really makes it look a little different so

29:40

No real solid component. There's this girl

29:43

rather decent sized left lower lobe Brown

29:46

glass maybe a reticular lesion. You could potentially say

29:49

it's it's one of these quote subsolid nodules on

29:52

the previous way, but looking at it in a little detail. This

29:55

is the same case you just a slicer two down

29:58

and you'll see

29:59

A lot more complex components to it. So

30:02

there may be is like a peripheral thickness to

30:05

it, but mostly like a bubbly look but rather

30:08

large lesion overall.

30:11

So again, these other planes really really help show the

30:14

actual structure to this and I'll show you

30:17

why it's not as easy when when these things

30:20

are growing.

30:21

So this was the same case two years prior and

30:24

you'll notice there's rather larger cystic

30:27

component to on the

30:30

image on the left, but you still saw this somewhat like reticular almost

30:33

ground glass bubbly look structure to

30:36

the same portion of it on the image on

30:39

the right.

30:40

So we can go back further and go four

30:43

years back and there still

30:46

is something there and that largest cystic area was definitely

30:49

present and it had a much less obvious component

30:52

next to it that became that sort of

30:55

reticular look. So this is

30:58

rather interesting and oh, well, we can actually

31:01

go farther back. So if you go six years back that cystic

31:04

component was not as well seen but it

31:07

was definitely present and had only just some ill-defined pair of

31:10

brown killer area to it on the anterior margin,

31:14

but then we can go even further and this

31:17

is where it's really hard to really Point look back

31:20

and say if this was an action the actual same lesion, so

31:23

if you notice on the image on the right, there was definitely

31:26

some other confounders other consolidation. So something else

31:29

is going on and it's easy to blow past this and

31:32

you probably wouldn't have really noticed it but I want

31:35

you to look at the image of the coronal playing on the left on the

31:38

right side of the screen.

31:39

And that does have a relatively simple

31:42

looking cyst component to it. So I think coming back

31:45

to the the more recent case. This is

31:48

how slow these things can grow and they can get quite large before

31:51

they actually are complex. But these are

31:54

not the gonna be the most common ways. This is going to happen. So these

31:57

features that we see on these larger lesions can definitely

32:00

start as small lesions and become a more

32:03

invasive lesion much faster, but they're very

32:06

interesting to bring up these concepts of how do

32:09

how do we really work this up? If you saw the solution now, they're

32:12

not many people would want

32:15

to biopsy because there's not much to biopsy. It's quite a

32:18

large lesion. So a surgical approaches a little extreme as

32:21

well. But the interesting part about this one a short-term

32:24

follow-up was made with the with an actual pet but at

32:27

this point six months after that initial that

32:30

last one there's definitely

32:33

a solid component at this at this stage. So thankfully

32:36

this was then able to be

32:39

acted on

32:39

the pet was actually rather positive, but you'll

32:42

see some lesions that have a similar amount of the complexity

32:45

of reticulation and not even a solid

32:48

component and they'll have very minimal fdg uptake and

32:51

that's where we're going to really need to use these morphologic features

32:54

and that complexity or particularly the

32:57

progression and how they've changed over the over the

33:00

course to to really know what

33:03

we're doing here instead of waiting until there is a much more

33:06

solid component to this.

33:08

So one of the last cases I'll go

33:11

into which I think is very interesting too and brings

33:14

up another important concept. So this

33:17

is another retrospective case and and brings up to

33:20

where covid-19 fits in.

33:23

So if you had a case.

33:25

This is one of the earliest.

33:28

Points we found this lesion so really wasn't described as

33:31

much I think maybe the mentioned some

33:34

thickness the image on the the right shows but

33:37

really it was probably considered scarring

33:40

and nothing was really made about it. So you have

33:43

the I would like you to note though that we should

33:46

not the actual image on the left does show some what

33:50

irregular kind of cystically and it's

33:53

hard to tell the wall. But now that we know that there's potentially a

33:56

solid component related to it that's gonna

33:59

peek my interest. So because of that follow up

34:02

in about a year and a half

34:04

did show us some substantial

34:07

change, but when there's a lot of other features around and

34:10

other parts of the lung there was

34:13

a description made of this and it was called possible scarring or

34:16

maybe they were developing solid components, but I'm

34:19

more short-term followup was recommended, but it wasn't

34:22

it wasn't really something to act on yet and then

34:26

We get a little farther along so that 1.5 year

34:29

to the three years. So another year and a

34:32

half. So the the follow-up was a little spotty once we get to this this

34:35

stage thankfully a more experienced radiologist

34:38

caught this and even straight up called it a

34:41

developing invasive pulmonary endocarcinoma. So that

34:44

should have rang a lot of bells and unfortunately, the

34:47

the actual follow-up would have had to have

34:50

occur at the beginning of the covid-19 pandemic. So unfortunately that

34:54

didn't happen and then the next presentation of

34:57

this patient was three more years after that and we

35:00

come up with our obviously speculated

35:03

nodule that has developed quite a

35:06

significant plural involvement. And then I think we all

35:09

know what this is.

35:10

So to really show and kind of bring this all back

35:13

of what how these lesions progress and

35:16

all the features potentially being involved showing that

35:19

Baseline of having an actual cystic lesion, which

35:22

again is very difficult relative to areas of

35:25

emphysema at times but it's always good to be mindful of the even

35:28

subtle things of that little bit of thickening that might be there

35:31

on that coronal and then in a short shorter term

35:34

follow-up to see the actual solid components develop but the

35:37

relationship with the cystic Parts is the most important

35:40

and I'd always caution to be mindful that sometimes when

35:43

you have these cystic components and the solid

35:46

components develop they can sometimes cause collapse of

35:49

areas. So it makes it really tricky and that's why these having

35:52

these multiple follow-ups and really looking at all. These features is

35:55

important because a decrease in

35:58

size of a cystic component potentially is not necessarily a good

36:01

thing. If you have these other more complex components involved

36:04

as well. And then as you can see at the six here in the

36:07

speculative lesion is still related to some of

36:10

the

36:10

cystic areas

36:12

but overall I get to

36:15

To remind you of the kind of

36:18

main thing that I like to approach most of these lesions and

36:21

that instead of just a nodule or

36:24

a ground glass or whatever you want to call it. I think looking at

36:27

these lesions as the components and then taking a

36:30

step back and thinking about if they have multiple of these

36:33

components they'd be considered complex. And those are the

36:36

ones we're gonna want to watch a lot closely and thankfully a

36:39

lot of this is all validated now in the the

36:42

newest long rides version and look forward

36:45

to the further follow-ups of all the

36:48

other Society like fleshner Society with having a

36:51

new glossary coming out in the near future. So all

36:54

these things will help help give us a little bit more guidance

36:57

to further clear characterizing these different

37:00

lesions and seeing how they fit in

37:03

the whole workup of lung cancer. So,

37:06

With that I just had a few of these resources. Like I really

37:09

encourage everyone to look at the acrs resources. They're

37:12

quite great because the you know, it is a

37:15

lot of updates that we're always going to be getting. So I think that's something

37:18

everyone should always have available to them. The other

37:21

thing I really like is the the incidental findings have been

37:24

really great. They've really streamlined a lot of the incidental findings for

37:27

long screening and put them in one location. So a lot of the white

37:30

papers are distilled to that so I think

37:33

that's definitely gonna be very helpful for everyone and

37:36

I think we always have to be mindful that most of long screening

37:39

is done by non-thrastic trained Radiologists.

37:42

So I think this approach should be helpful to

37:45

pretty much anybody because you're mostly more

37:48

than likely going to be dealing with these lesions no

37:51

matter what whether you're in neural or an abdomen and you have

37:54

those shared portions of the lungs, so

37:56

With that I'll conclude and we can

37:59

start looking at some questions.

38:13

So the one main question I have here is that are these

38:16

lesions you showed our carcinomas? So yeah,

38:19

most of most of these lesions that I showed or

38:22

were pulmonary adenocarcinoma's.

38:26

And then subsolid that that's kind

38:29

of looking at probably the distinction between

38:32

a ground glass lesion that

38:35

doesn't have the solid components but then also

38:38

may have other cystic components to

38:41

it. So the way I always interpreted the the subsol

38:44

lesions were something that was

38:47

cystic or potentially had ground glass components, but

38:50

really no true solid component and that's kind

38:53

of how it would fall under this whole complex idea

38:56

rather than just a ground glass

38:59

because it pure ground glass would be a

39:02

little bit more of a simple lesion without any cystic component

39:05

or any solid component.

39:07

and then

39:09

I have

39:11

asking about

39:13

a simple and a non-complex cyst so

39:16

well if that's

39:19

so a simple cyst is not going to be followed as part

39:22

of the bung rats. So in that table the the

39:25

very first point talks

39:28

about a thin walled cyst being less than

39:31

a two millimeter wall. And those are going to be followed and

39:34

most and most often too. If you

39:37

had multiple of those similar cysts. Those would

39:40

probably likely also fall under a more diffusing

39:43

disease. That was also in the very last

39:46

point of the the cystic part of the table, so

39:51

Oh, this is a good question. So do

39:54

you find that clinicians are less likely to act on

39:57

a growing cystic lesion until they develop a

40:00

solid component and that's definitely the the major

40:03

problem with this because I think

40:06

one of the the big parts of the actual follow-up

40:10

that that is a whole different talk in

40:13

itself probably and it's probably very institutions specific.

40:16

The the actual follow-up is

40:19

probably best for these low growing lesions to

40:22

be the another low dose that three

40:26

months to either confirm that something's growing.

40:29

Because often You're Gonna Catch these growing either complex

40:32

laculations or a very

40:35

subtle thickening that really still would not be

40:38

probably okay to biopsy. So we found a lot

40:41

at our institution that it's at least better to

40:44

do these shorter-term follow-ups and engage the patient and maybe

40:47

have their thoughts because not every

40:50

patient is gonna want to be as aggressive but some might want

40:53

a lesion out. So bringing up that very large multilocular

40:56

cyst if that patient was

40:59

rather conservative and did not want to act the it

41:02

was probably okay to follow that but if that patient

41:05

really wanted that out taking that out

41:08

before it got to plural involvement would probably have

41:11

been a been a good thing for them if they

41:14

wanted to choose our route. So I think the multidisciplinary approach and really

41:17

looking at what your institution would want

41:20

to do because if you have a lesson centimeter solid

41:23

component, sometimes the biopsies are a little tricky. I

41:26

know summer more more gung-ho than others, but

41:29

and then having it more of a conversation and the multidisciplinary

41:32

approach for those higher up for be lesions

41:35

and are very important.

41:37

So

41:39

Now the part out of another question about the features that are

41:42

surely effective or inflammatory. So there is

41:45

a little detail in the table about that of something

41:48

that grew so fast, that would be

41:51

less likely to be a cancer or if you had any interim finding

41:54

sauna if those are

41:57

some of the things and it really is not easy. If you did not

42:00

have a prior to show that there was no lesion and I think this is very

42:03

important for some of these these lesions

42:06

that develop after there was a small cystic

42:09

space like this if you look and you see a new

42:12

nodule whether it's not that large, but if it was in the exact spot

42:15

is that that small lesion I would

42:18

be much more worried about that. So really you kind

42:21

of have to have those priors, but if you don't just a

42:24

very multiple, you know

42:27

multiplicity of nodules that are more ill-defined and then

42:30

the clinical picture. Those are the type of things that you have to

42:33

look to but yeah, there's really

42:36

not a good way to do that.

42:39

and then

42:43

okay, so a complex cyst that increases in volume in less

42:46

than a year.

42:48

So if it is a complex system, it increases slower. So

42:52

as part of the table there there they do allow

42:55

a for like a very slow growing lesion to be

42:58

lumped into the the category of the four categories, but I

43:01

think this is where you really need to have

43:04

look at those subtle other features. And if

43:07

I personally if there is these is

43:10

a growth of the complexity that really doesn't

43:13

fit into one of the categories. I really have

43:16

no problem with continuing with like a six-month or

43:19

or even a three month to then another

43:22

six months at the very least to do a shorter-term follow-up.

43:25

If you don't feel comfortable really putting

43:28

it back to a category too and waiting

43:31

another year. So any of that complexity does allow you

43:34

to do that shorter-term follow-up now thankfully with

43:37

long rats.

43:39

And then oh, this is a good question about biopsying of

43:42

these growing cysts. So the biopsy of

43:45

these lesions that have almost no solid component

43:48

is not not usually what most people are going to be doing. I think

43:52

if you have proof that you you show the

43:55

way this is growing and there's a likelihood that it could

43:58

become a an invasive adenocarcinoma

44:01

in the future. I think then again, that's the

44:04

conversation with the patient and the Comfort level of of

44:07

maybe a surgeon if they would want to take it out and that

44:10

also will then make sure you have to

44:13

look at a case as a whole because a lot of times patients will

44:16

have several of these lesions and I've seen

44:19

plenty where there are some that are slight

44:22

more complex than others in the even though the complex ones are

44:25

more worrisome at the time. They will stay stable

44:28

and then one of the less suspicious or

44:31

simply lesions will blow up and that's that one ends

44:34

up being the invasive cancer. So that's something to be

44:37

very mindful of because you wouldn't want

44:39

go after one that not necessarily was the was

44:42

gonna be the most likely so I think doing the shorter

44:45

can follow-up is the best bet in most of these cases.

44:49

Okay.

44:51

ah good question about what are the characteristics that

44:54

lead to recommending a pet as the follow-up so

44:58

I think again the patient should definitely be involved in this but if

45:01

you really don't have

45:03

solid components over the eight millimeters and you

45:06

can't show that this has definitely grown from

45:09

a less complex lesion.

45:12

That's for sure relating because if you

45:15

don't have the absolutely relation you had maybe a baseline case

45:18

that showed one of these slightly complex lesions and

45:21

had the solid component in that case. I

45:24

would definitely be mindful of a pet where if

45:27

the solid component is big enough and over eight. You could probably

45:30

get a positive result. But if you do get a negative or

45:33

equivocal pet I would not stop

45:36

there. So I think that's the the beauty of the

45:39

new classification. Whereas even if you did demonstrate that

45:42

there wasn't a significant FD job

45:45

take there. You would still want to do a shorter-term follow-up rather than

45:48

just suddenly go back to a year follow up.

45:51

So I definitely think going by the solid components

45:54

because you'd only get lucky in a few rare cases

45:57

like those that really larger lesion that

46:00

I showed in the left lower lobe that had enough

46:03

Consistent kind of complex components that were

46:06

around for a long time that that did have some uptake. But

46:09

if that was neg negative or equivocal I

46:12

would not have taken that I would have been a false a false negative

46:15

for me on the pet. So I think that's definitely something

46:18

and yes, we I think

46:21

most most of our institution does have the ability to somebody

46:24

asked about having the patients have a copy of the

46:27

reports and they do have the ability to read the reports through Epic.

46:31

and then

46:34

often the genetic data available at the time.

46:38

I do. I don't think we have any genetic Avail data available

46:41

at the time of the CT interpretation. That's definitely something we're

46:44

not there yet. So I really have no experience

46:47

with that.

46:49

mmm

46:52

This is a good one the risk of an athorax for biopsying

46:55

these complex this so I think with any lesion that's

46:58

peripheral. You have to be mindful of

47:01

the risk of pneumothorax. But particularly if you

47:04

do have such larger cystic components

47:07

in these These Are Gonna potentially be

47:10

ruptured if they are at this superficial portions of

47:13

the lung and there would definitely be a risk of pneumothorax there. So I

47:16

think that's definitely why it's not going to be the same

47:19

case for every patient depending on where these lesions are

47:22

located. So, yeah, it's definitely something that should be involved in

47:25

the discussion.

47:27

And for a short-term fall what I mean for most of

47:30

these so if you did have a lesion that you that you

47:33

couldn't really fully put into the category three

47:36

and wait six months. I think if you can

47:39

see some of these features that would allow it

47:42

to be more of like a growing a growing complexity to

47:45

the nodule that portion would get you

47:48

to go to the four which would then be the the three-month Lotus

47:51

follow-up.

47:53

and

47:58

the chance of a

48:01

of a growing slowly growing cyst of becoming the

48:04

cancer. So I definitely encourage looking at that that article

48:08

from 2018 the radiographics article that looked into

48:11

the the actual numbers of

48:14

these cases that had like nodger components

48:17

but they're trying to look at cysts in the I think

48:20

the most important thing that we need to do now is do a lot

48:23

more the they definitely pointed out the lack of of really

48:26

the how we've addressed that problem of

48:29

like a peer cyst that maybe didn't

48:32

have any solid components and those growing because I

48:35

think now that we're aware that these potentially would

48:38

become lesions like that. I think now we're

48:41

gonna be able to go back and do a better retrospective analysis. But

48:44

right now that really really hasn't I

48:47

haven't seen anything that really was throw enough to

48:50

really look back at the the more simple cysts because just

48:53

getting this

48:55

The awareness of the complexity for even something that has been

48:58

discussed since the 1940s. It's only just recently

49:01

been included in the lung RADS. But I

49:04

think it will be something we definitely need to learn more about because I

49:07

personally think if you do catch one of these

49:10

things and it starts to get slightly more complex, I would

49:13

love a rather less invasive way to treat these

49:16

lesions, but it's definitely something I'm

49:19

looking forward to to seeing in the future because if

49:22

you can stop these from growing rather than just getting serial CTS.

49:25

I think that would be wonderful.

49:28

so

49:29

anyway, we had a couple questions in the chat come through

49:32

if you're up for it. I can read those to you.

49:35

chat

49:37

Yeah, the first one is what is the PET CT size Criterion

49:40

for long lesions, for example, the minimum size of

49:43

a suspicious lesion also, which of the published guidelines

49:46

do you use for assessment of solid pulmonary nodules?

49:50

For yeah, so the first part about the pet I

49:53

think going with a solid component of eight

49:56

millimeters is what our institution uses and

49:59

the only other case of potentially a

50:02

higher complexity would potentially be

50:05

one that would be used but this is where

50:08

I really have a hard time with like the actual

50:11

action because every single

50:14

patient we've discussed in these different categories with

50:17

calling these atypical pulmonary cysts, or these slow growing

50:20

lesions that we've looked back and found that word present

50:23

just our developing these features rather slowly every single

50:26

patient seems like is being approached differently. So

50:29

it I don't think there really is a hard recommendation right

50:33

now that will steer us to just a simple

50:36

answer because all these lesions are quite different and

50:39

that's that's what I've found.

50:43

Okay.

50:46

Oh, it's bringing up the concept of fleshner guidelines

50:50

and then long RADS was closed.

50:56

Oh, yeah, so bringing these guidelines together

50:59

is definitely what is what is happening now, so the

51:02

previously in the past there

51:05

was definitely a discrepancy of the kind of

51:08

low the low threshold for what a suspicious

51:11

nodule was between like four millimeters or six millimeters and

51:14

I think they're at least coming together and becoming closer with

51:17

the six millimeter threshold of being for

51:20

us like a solid nodule and if

51:23

there aren't any of the other suspicious features those those

51:26

nodules will be considered micronodules the smaller

51:29

nodules and those won't have as much action. So these updated

51:32

guidelines as they come together will be a little

51:35

bit more consistent, but that was definitely the gripe years ago of that

51:38

even long screening was a little astringent than the

51:41

original fleshner. So that was updated in 2017 to

51:44

at least be more on the same page. And as we

51:47

move forward in the new guidelines come out and new glossaries

51:50

for for maybe the flight center glassery, you'll

51:53

you'll see that they'll likely come together.

51:56

Little bit more and help explain some of this because I definitely

51:59

had heard that this discussion on the typical

52:02

cyst was one of the more interesting ones at the at the

52:05

home rights committee because there are a lot of people

52:08

have different opinions on it and it's not so simple to give a

52:11

blanket recommendation.

52:13

for some of these things

52:24

Yeah, so talking about the like a

52:27

post treatment scan and whether dealing

52:30

with like the checkpoint Inhibitors or small molecular monoclonal antibody

52:33

therapies. I don't think there's anything right now

52:36

that I would be comfortable you don't breaking

52:39

away or doing something different based on what what

52:42

is the medication but I think

52:45

again those are gonna be getting more and more specific based

52:48

on the patient's genetics and how they're

52:51

responding these therapies. So I don't

52:54

think giving any sort of blanket recommendations will

52:57

help with that.

53:02

Distinguishing between adenocarcinoma consolidation

53:05

and infectious consolidation. This is

53:09

definitely something that is not super easy. But here's this is

53:12

where if you don't have a prior exam and you're you're

53:15

stuck with a a mask like consolidation or even a

53:18

nice quote unquote suspicious nodule or complex nodule with

53:21

speculations.

53:22

It does come down to clinical picture

53:25

and if doing doing

53:28

the treatment if there was suspicion of infection

53:31

and then you just have to do a follow-up after treatment

53:34

and I know that even a maybe like six

53:37

to eight week follow up after a completion of an antibiotic

53:40

course would be something to consider. But then

53:43

I also have to take into the the count the

53:46

patient's risk factors and a lot of other things and that so

53:49

that that's usually how I approach that concept.

53:53

I think that might be all of them.

53:56

Well, Dr. Smiley, thank you so much for your lecture today and thanks.

54:00

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54:03

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54:06

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54:15

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54:18

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54:21

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54:27

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