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Dr. Finazzo, this is a 62-year-old woman who had a CT.

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3 00:00:04,880 --> 00:00:07,770 Here's the coronal reformat demonstrating a

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mass in the right kidney with some nodularity

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that enhances inferiorly, a somewhat

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cystic, but not a pure cyst, obviously.

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Uh, mass with nodularity in

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the upper part of the lesion.

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So, why do we do an MRI in this case?

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What are the biomarkers that we're

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looking for to enhance diagnosis?

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Yeah, so in here, uh, already, the fact that

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there's an enhancing component already places

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this at high risk of being a renal cell carcinoma.

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And as we know, renal cell carcinoma cancers

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can invade vein and can have metastatic disease.

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And even though we want to think that CT is good

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to look at METs, the MR really adds a little bit

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better value, especially to look at small mesenteric

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lesions, or lesions that tend to fall into the

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pericardial gutters, and small hepatic lesions.

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But when we're talking about the actual

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lesion itself, we can potentially offer some

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histologic grading by using the diffusion

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weighted images to look for central necrosis.

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If a higher aggressive clear cell RCC is more

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aggressive, it will have diffusion restriction.

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But in this case, we do see that we have a

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complex cystic lesion, uh, in the right kidney,

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which demonstrates strong arterial enhancement

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on the early phase and areas of nodularity.

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Uh, and then when we actually zoom down on this

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image, we can look at the rest of the abdomen

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to look for subtle lesions in the kidney.

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This one we, I already know is a cyst because I've

1:52

already reviewed the case, but it's small renal

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lesions can present that small and

1:58

we're looking for ring-enhancing lesions

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similar to the primary tumor in the liver.

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We look at the renal vein and the portal vein to

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make sure, I'm sorry, the renal vein and the IVC,

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to make sure that we don't have any venous involvement.

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And we really try to scrutinize

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the, uh, retroperitoneum.

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And while I'm on the post-contrast images,

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I do a quick search of the spine to make

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sure we don't have any metastatic lesions.

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And I look at the soft tissues, which is why we

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like to use fat-suppressed, uh, post-contrast

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imaging because renal cell carcinoma lesions will

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light up like a light bulb in the soft tissues.

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Yeah, and they do like the soft tissues, and

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it's also one of the hypervascular metastases.

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And I have been burned on CT, whereas on CT, you know,

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you, you have the cava, and the cava has enhancement.

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So if you put inside that a very

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hypervascular lesion, it's enhancing.

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It blends right in with the contrast in the

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flowing blood, and you can actually miss it.

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Whereas on a non-contrast MRI, you've got fast flow,

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but if you put a solid lesion inside without giving

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any contrast, you're going to see a solid-looking

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round defect that may be adherent to the wall.

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So actually in my experience, renal vein invasion

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and caval invasion is much more easily seen

3:18

on MRI than it is on contrast-enhanced CT.

3:22

One last caveat you've mentioned to me on numerous

3:25

occasions throughout these vignettes, it's the

3:27

Bosniak classification, so that our colleagues

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don't have to fumble through it.

3:31

We will post that at the end of this vignette.

3:33

Alright, P and P out.