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A 65-year-old with a PSA of 6.5, a benign gland on

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exam, obstructive urinary symptoms, and most

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importantly, multiple prior negative biopsies.

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So we have the axial T2, the ADC map windowed at 1400 1400.

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The B equals 1600 interpolated B value image.

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And this is actually a delayed late phase

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post-contrast series, not the early phase.

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But I'll explain later why I'm showing this picture.

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So again, I always start within the peripheral zone.

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And here the peripheral zone is

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uniformly or near-uniformly T2 bright.

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There's a small error of heterogeneity.

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On the ADC map, the peripheral

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zone is almost uniformly bright.

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There is no focal area of well-defined diffusion restriction.

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This looks like one, but if we look ahead,

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we're going to see that it's actually going to

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be a nodule in the transition zone, so we're

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not going to put that in the peripheral zone.

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So nothing suspicious in the peripheral zone.

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So next, we'll jump to the transition zone, and the

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transition zone here has this multi-nodular appearance.

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And these are all kind of normal.

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There are some nodules, but they're well-defined.

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They have well-defined margins.

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Uh, it's all normal fun, and it's gonna

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be some low signal in the stroma that

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goes between the left and right lobes.

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And if we go very high, the transition

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zone protrudes into the bladder base.

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There's one area I'm gonna call

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attention to, which is right here.

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So this has all the appearances

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of a neoplasm in the transition zone.

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It's well-defined lenticular-shaped

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low T2 signal and it's anterior.

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And you might be tempted to say, well, this is anterior

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stroma, but it's not where the anterior stroma is.

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This is transition zone.

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This is the anterior part of the peripheral zone.

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You can see it's all the way bright around here.

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So anterior stroma is going to be located anteriorly.

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So, so this is not anterior stroma.

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This is a PI-RADS 5 lesion in the peripheral zone.

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Sorry, in the transition zone.

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Uh, it's gonna measure more than 1.5 centimeters in diameter.

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That's why it's a PI-RADS 5 lesion.

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It's well-defined, low T2 signal, lenticular-shaped,

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and very much stands out from the remainder of the transition zone.

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Now the T2 appearance alone allows you to call

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it a PI-RADS 5 lesion, but you'll also notice it

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is well-defined on the ADC map as a black hole.

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The ADC value of this was low.

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It measures a mean of 630, which is

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very low, and it's also focally bright

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on the high B-value image.

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And so this is a PI-RADS 5 lesion in the transition zone.

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And if we scroll throughout the remainder

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of the prostate, there's nothing else that

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looks suspicious in the transition zone.

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All right.

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We can very quickly look at the central

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zone because we should always do that.

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So I need to bring up the coronal images

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and still on the wrong window here.

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So we have transition zone, sorry, um,

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central zone, not very well seen here.

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So now this area corresponds on the axial images

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to what we called was the PI-RADS 5 lesion.

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And this area anteriorly is going to be thickened stroma.

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So let's look at that thickened stroma on the axial images.

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That's here.

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So a couple of things to notice that differentiate that.

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from the transition zone, PI-RADS 5, highly

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suspicious for neoplasm that we saw.

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One is, this is actually located along the anterior

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margin of the gland, so here's Transition zone, and

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this is outside the prostate, so it's not located

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between the transition zone and the peripheral zone.

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Second, it crosses the midline, it's very

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smooth, and it almost just looks like

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thickening of the anterior margin of the gland.

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It's not avidly restricting diffusion.

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It really has no appearance on the high B-value,

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although sometimes, It can be dark on here

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and bright on here, but in this case it's not.

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And in addition, it shows no enhancement.

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So here it is here, and here it corresponds

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to this dark rim right here on the delayed

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post-contrast images, no enhancement.

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If you look at the tumor, the suspected

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tumor, that is enhancing, right?

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So if I saw something like this in the anterior

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stroma, I'd be worried it was neoplasm.

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But remember, this isn't where

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the anterior stroma is located.

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This is where the transition zone is located.

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So, we do the rest of our check.

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The seminal vesicles are completely atretic.

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There's nothing in them.

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There's no abnormal soft tissue sitting

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where the neurovascular bundles are.

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The angles between the rectum and

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the prostate aren't obliterated.

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That kind of makes sense.

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This tumor is anterior.

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When this was biopsied, this came back as

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four cores with Gleason 3 plus 4 disease.

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So, that's a significant cancer, and the reason this person

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had a normal palpating gland is the tumor's anterior.

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You palpate the gland, you palpate posterior, and the

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reason they had multiple prior negative systematic

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biopsies is this is an anterior tumor, and when you

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do transrectal systematic biopsies, the needle comes

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from the back, and the needles are often only 1.5

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centimeters long.

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This part of the gland would not have been sampled.

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Okay, so in summary, we have a PI-RADS 5 lesion that had

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a concordant positive biopsy finding, which is distinct

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from an area of normal appearing anterior stroma.