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This is the case of a 85-year-old male with history of

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high grade prostate cancer that was started on

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hormonal therapy and his PSA levels improved, but

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after a while on treatment, they increased again

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and started to progressively rise.

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A-P-S-M-A pity was done for evaluation

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because this was suspected to be a biochemical recurrence.

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And this is the case that I'm showing you

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in the ME images we see that there's multiple areas

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of abnormality, particularly in the pelvis

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and along the retroperitoneum.

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Let's just start evaluating the pelvis.

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In this case, we have intense tracer uptake in the prostate

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gland that looks otherwise atrophic or small.

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This indicates high volume of disease.

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Aside from that, we can see there are in the pelvis multiple

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sites of tracer uptake.

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However, when we look at the study on the axial plane,

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you can appreciate that on the PET only image there is a

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halo around the bladder

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and this is an artifact that you might encounter.

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And this is the result of attenuation correction

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because there is intense uptake coming from the bladder.

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So one of the things that you could do to

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reduce this artifact would be

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to look at the non attenuation corrected images

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and look at the raw data

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or if you had, there are available post-processing tools

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and algorithms that help reduce these halo artifact.

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Let me show you what we have on this patient,

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which is the non attenuation corrected information.

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So on the top we have the CT portion of the pelvis.

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Uh, the second row is that non attenuation corrected pet.

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The third is the attenuation corrected pet.

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And then the last row is the FS data with the CT

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and the AC pet.

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So look at the difference of these between the two pets.

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Uh, in the raw data you have actually recorded events

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around that bladder.

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If I don't have access to post-processing tools,

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I would use this one to travel shoot just to make sure

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that I don't miss the small lymph

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nodes surrounding the bladder.

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In this case, I do not see lymph nodes that are adjacent

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to the bladder to indicate that there was novel disease.

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I do start seeing other lymph nodes

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that are involved bilaterally,

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but in this case I can already see them on the AC data.

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So let's go back to the initial display.

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We have multiple no

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Stations that are involved in this patient

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bilaterally extending from the external iliacs

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and including for instance, these very intensely

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P-S-M-A-A lymph node anteriorly all the way

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to the common iliacs presacral space.

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And if we continue scrolling up, we see

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that the novel disease extends into the erum

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and look at the intensity of the tracer compared to the size

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of these lymph nodes that measure approximately up

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to four millimeters is all represents disease

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and going up, we can see even a focal uptake in a tiny lymph

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node at the D pragmatic cura

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and always continue to look at the posterior mease at

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as this is the, the common pathway of NOLA spread.

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In this case disease was seen in the left supraclavicular

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molestation indicating the presence

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of distant S noal disease.

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Aside from those findings, this patient also had

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a metastatic lesion in the right lesion

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where you can see that there is a focus of sclerosis

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that correlates with that focal uptake on the PET imaging

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as well as a focus of

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uptake in an sclerotic lesion in a rib.

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We have a trace

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or faint focal uptake in this vertebral body

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and there was no visceral metastatic

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disease on this patient.

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So to recap, this is a patient that

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was undergoing hormonal therapy

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for high risk prostate cancer that initially responded,

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but due to increasing PSA levels, the PSMA was performed.

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This PSMA PET reveals that there is

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a large volume of PSMA AVID disease in the prostate gland.

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There is novel disease that is both

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regional and distal

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or metastatic as well as OS osteos metastatic disease.

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In this case, we've also learned how

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to troubleshoot when there is an artifact from intense

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bladder uptake in the pelvis.

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In this patient, it was incidentally found

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a right upper lobe nodule that

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didn't show PSMA uptake and this was suspicious for

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and later confirmed to be a lung primary.