0:00

Let's continue along the framework

0:02

of T stage classification, but I want

0:04

to focus for a minute on pathologic

0:06

classification, so-called PT staging.

0:10

P standing for pathology.

0:12

Now why do I want to show you this?

0:14

My goal is for you to have a framework

0:17

of what's important as you ascend the

0:19

unfortunate ladder of more advanced stage.

0:23

Also, when you're looking at a pathologic report,

0:27

it's nice for you to be able to understand

0:28

what that report means, so you can go back and

0:31

correlate and see how well you're doing, what the

0:34

MRI missed or made, and even going forward, if you

0:37

have a biopsy and you have a follow-up MRI, this

0:40

will help you make an appropriate correlation.

0:43

There is no, by the way, pathologic staging

0:46

that correlates with the clinical and/or imaging

0:49

staging in these early stages from TX to T1C.

0:54

And in fact, there's no imaging

0:55

correlate from TX to T1C.

0:59

So PT2, pathologic T2, the

1:02

cancer is confined to the organ.

1:05

In other words, I'll take the cancer and

1:08

make it deep red or maroon. The cancer

1:11

stays inside the prostate; it doesn't

1:14

go outside this capsular, uh, margin.

1:18

PT2A.

1:19

There's unilateral involvement

1:21

of one half of one side or less.

1:23

So we might have something like

1:24

this, but it doesn't involve the

1:27

other 50 percent below down here.

1:30

PT2B.

1:31

There's unilateral involvement, but more

1:33

than one half of one side, so the volume

1:36

of involvement is greater than 50%.

1:39

That's very straightforward, but there's no

1:41

contralateral involvement of the opposite lobe.

1:44

Bilateral disease; the opposite lobe is involved.

1:47

It's self-explanatory.

1:49

And we have midline crossing.

1:52

Extraprostatic extension, PT3.

1:56

We've got PT3A, extraprostatic extension.

1:59

Or, microvascular invasion of the bladder neck.

2:04

Now this is macrovascular invasion,

2:05

which we're good at seeing.

2:07

Microvascular invasion, not so much.

2:10

Now in patients with microvascular

2:13

invasion, a positive surgical margin

2:15

should be indicated by an R1 descriptor,

2:18

which means residual microscopic disease.

2:21

But that's a pathologic designation only.

2:24

Not imaging and not clinical.

2:27

Then we have PT3B, seminal vesicle invasion.

2:31

The seminal vesicles, which we'll draw here

2:34

in, say, blue, kind of coming off to the side.

2:37

An MR is excellent, even without DCE

2:41

or Dynamic Contrast-Enhanced MRI at

2:43

picking up seminal vesicle invasion.

2:46

And finally, PT4, invasion of the rectum,

2:50

levator muscles, and or pelvic sidewall.

2:54

Now let's talk about more distant

2:56

disease, just for pathologic staging.

2:59

Not for clinical staging, not for imaging staging.

3:02

We've got PNX, regional nodes were not sampled.

3:06

PNO, no positive regional nodes, and

3:10

PN1, metastases in the regional nodes.

3:14

Very simple.

3:15

And you see the distant metastasis

3:17

staging, which is not necessarily

3:19

pathologic that we'll discuss separately.

3:22

We'll have a link for this on your MRI

3:25

online, uh, visualization of this vignette,

3:28

so you can click over and look at the,

3:30

some of this information in static format.

3:34

Let's move on, shall we?