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Let's take a look at this lung cancer screening CT

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and a 75-year-old woman with a 40 pack year history

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of cigarette smoking with 14 years since quit,

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so still remains eligible under the 15 years since quit.

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Criterion, she's asymptomatic,

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but she delayed her lung cancer screening due

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to the Covid pandemic.

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She had been screened earlier in 2019, in the summer June,

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and now comes in February, 2021

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for her lung cancer screening.

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You can see from the top of the lungs the not uncommon,

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mild, upper and mid lung predominant central lobular

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emphysema that we see in patients

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with a cigarette smoking history.

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It's a little bit of fullness here in the right hilum,

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but I see some calcification through the lung windows.

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A little bit of loation here

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that we don't expect at this location.

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Let's keep looking small airways.

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Don't look particularly thick, don't see any moid impaction,

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and a little bit of mild dependent ectasis,

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which we know we see more common in people as they age

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and in individuals who smoke versus those who don't.

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Um, let's look at the soft tissue windows a little bit noisy

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as we expect due to the low dose exam.

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As we come to the level of aortic arch here,

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we're seeing an enlarged lymph node in the right

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parit tracheal region.

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If we measure it in short axis diameter,

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we're getting 21 millimeters.

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So that definitely meets the criteria

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for an enlarged lymph node

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and we see more enlarged lymph nodes here in the right parit

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tracheal region here next to the aorta.

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And that right hilum is bothering me

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because it's lobulated in an area

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where there shouldn't be any loation.

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The pulmonary vessels aren't coming out yet.

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They're a little bit lower down here,

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and there's this fullness here behind the SVC,

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we see normal mediastinal fat around the ascending UTA

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and interdigitating here in the Precarinal area,

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but right here where we expect to see the SVC,

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there's not any fat behind it.

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So I'm concerned about this area here.

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Admittedly, it's very hard on a non-contrast CT to look

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for hilar lymph nodes,

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particularly when they're just mildly enlarged.

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If we have a comparison

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and can compare the shape

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of the hilum today versus the shape of the past

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and see a change, that can be a clue when

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you have a first time ct.

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It's a big challenge to identify enlarged hilar nodes,

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particularly the mildly enlarged ones.

2:32

So we already have a non pulmonary finding.

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We didn't come across a lung nodule,

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but we did find this extra pulmonary finding

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of enlarged mediastinal

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and potentially right hial lymph nodes.

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So next thing we're gonna do is we're gonna look

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for her baseline ct.

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And on the left here was her prior lung cancer screening CT

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from June, 2019.

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She had normal size right para tracheal node back

2:58

Then under a centimeter, just normal sized

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and we could see a little bit more fat

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behind the SVC than we can see now.

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And so it looks like the enlarged lymph nodes are new,

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definitely in the para tracheal region.

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A bit softer column on the right hilum, so not a nodule.

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So no nodule criteria to put it in. Lung RADS 2 3 4 4 A.

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But we have an extra pulmonary findings

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and I'm concerned about this being malignancy.

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So this is a lung RADS four x, not

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because of nodule features, but

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because of extra pulmonary features.

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This patient goes on to get a pet CT

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and you can see the enlarged lymph nodes in the right per

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tracheal region and down into the right hilum are all very

3:41

FDG avid and there similarly was no signal coming from the

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lung as being a source.

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Those patients subsequently underwent a bronchoscopy

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with AL aspiration through the bronchoscope

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of the right para tracheal

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lymph nodes demonstrating poorly differentiated

4:01

pulmonary adenocarcinoma.

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Even though like I said, we can't see the primary.

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Thus cellular makeup of the tumor is consistent

4:09

with a pulmonary adenocarcinoma.

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This is a stage three A cancer.

4:14

Fortunately for this patient, there was a high intensity

4:18

of the PD L one mutation 70%.

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So in addition to receiving traditional chemo

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and radiation therapy, the patient qualified for one

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of the immunotherapies

4:28

that are targeted based on the PD L one mutation.

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So she has a pembrolizumab treatment

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and had a very good response to tumor treatment

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and shrinkage of the tumor subsequently.

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So here we have that extra pulmonary finding

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of enlarged lymph nodes.

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PET positive new finding since

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of prior CT making this four x

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and was the reason for the diagnosis

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of lung cancer in this patient.