0:00

Okay, let's take a PI-RADS 4.

0:03

This is an 82-year-old with a PSA of 4.63.

0:07

The gland volume calculated

0:09

using the bullet formula, 36.5 cc's, which is above, uh,

0:15

the normal, which is 25 cc's.

0:17

Remember, the bullet is length times width

0:19

times height times 5 pi divided by 24.

0:22

Then you can take that number and

0:24

you can divide it into the PSA to

0:27

get the tumor density, which was 1.27 in this patient.

0:31

The patient has had a TURP, a Transurethral

0:34

Prostatectomy, to open him up.

0:37

Look at the two sides in the axial projection.

0:39

Let's scroll to the base, up by the seminal

0:41

vesicles, down more towards the apex, mid to

0:45

apical region on the right, looks different than

0:47

the left, grayer, fatter, more bulgy looking.

0:51

There's your TURP defect.

0:52

There's a nodule in the TURP defect.

0:54

Is this real?

0:56

Well, the ADC map says it's real.

0:58

The ADC map shows diffusion restriction.

1:01

With a pretty sharp edge

1:02

along the anterior margin.

1:04

In the peripheral zone, the PZ

1:07

lateral, posterolateral, PZL, and

1:10

PZP, posterior portion of the gland.

1:13

Let's turn our attention to

1:15

the diffusion-weighted imaging.

1:18

Let's start out with the B value of zero, which

1:21

is basically a T2 echoplanar VASPIN echo image.

1:26

Then let's go on to a B value of 50.

1:31

Is there anything getting brighter?

1:32

Not yet.

1:33

Let's try a B value of 150.

1:36

Anything getting brighter?

1:37

Not yet.

1:38

Let's go to a B value of 990.

1:42

Anything getting, getting brighter?

1:44

There sure is.

1:46

Let's go to a B value of 16 or 1500.

1:50

Is anything getting brighter on the right?

1:52

This is 1500.

1:53

Sure is.

1:55

So our major criteria of tumor diffusion

1:58

restriction, getting brighter, getting

2:01

substantially brighter, with a defined area of

2:05

low signal on the ADC map corresponding to an

2:08

anatomic abnormality on the T2-weighted image in

2:11

the PZ, the PZL, and PZP to be specific, are met.

2:18

Let's take a look at our DCE MRI to see if our

2:21

lesion has the typical characteristics of an

2:24

aggressive tumor, namely early hypervascularity.

2:28

So here we are at the mask, and here we

2:35

are at the 10-second interval, immediately

2:37

upon arrival, and indeed, immediately upon

2:41

arrival, this area, and this area right

2:45

here, correspond to this hypervascularity

2:48

in the right portion of the gland.

2:50

More than 50 percent of the volume

2:52

of the gland is involved on the right

2:55

side, so this would correlate with a T.

3:02

Now let's take a quick look at the

3:04

coronal, which has something to add.

3:06

It gives us an idea of the cranial caudate height.

3:08

So how apical is it?

3:10

Not all the way at the apex.

3:11

It's a little above the apex.

3:13

More apical to mid and mid.

3:16

So this is all a portion of the tumor.

3:18

Compare it with the other side.

3:20

So you have to use all projections.

3:21

Right side, bulgy, gray.

3:26

Left side, wispy and white.

3:29

The architecture is preserved.

3:31

We see lines between glands.

3:34

We see lines between zones.

3:36

All that is wiped away, almost like a charcoal

3:40

eraser has taken to the right side of the gland.

3:44

This is an example of a

3:45

PI-RADS 4 with a T stage 2B.