0:00

Best case I really like, the CT scan,

0:03

probably one of my favorite CT cases that I've come across relatively recently.

0:10

All right, so maybe I'll give you a little bit of history on this one.

0:14

This is a,

0:15

I think it was a 35, 40-year-old gentleman who had an ultrasound,

0:22

retroperitoneal ultrasound.

0:23

They couldn't find the kidney, the left kidney.

0:27

And when they scrolled down to the bladder, they saw a mass.

0:29

And so they thought that this was a...

0:32

that the mass in the bladder is the pelvic kidney.

0:34

And so they got a CT scan to further evaluate the findings.

0:38

And so they did it as a hematuria protocol.

0:40

And so I'll go through the different

0:41

phases for the hematuria protocol, just so that I present to you everything

0:45

that we would be presented with as we go through.

0:49

So, this is the non-contrast CT.

0:52

Recall, they couldn't see a left kidney

0:55

on the ultrasound.

1:01

And they saw a mass in the bladder, or the location, the bladder.

1:05

So we see something, perhaps, in the pelvis over there.

1:13

So that's our non-contrast CT.

1:16

Scroll through our contrast,

1:17

the nephrographic phase just goes through the kidneys.

1:20

So I'll just go start from the top again

1:22

and just sort of scroll through that, see if there's anything there that can

1:26

help you figure out what's going on over here.

1:31

And then I'll finish up with delayed image,

1:34

excretory phase, about 8 to 10 minutes out.

1:38

And this is going to go through everything.

1:45

So we're scrolling through,

1:47

scrolling through, scrolling through,

1:48

we get to this lesion in the pelvis, what they saw in the ultrasound.

2:02

And so, those are the axial images.

2:06

And let me just show you coronal excretory phase,

2:14

so you get a relationship

2:16

of what this mass looks like with respect to

2:21

some of the other organs, perhaps, that you're seeing in the pelvis over here.

2:26

And I'll show you sagittal,

2:29

excretory phase image as well.

2:37

Okay. So one more time,

2:39

I'm just going to scroll through the axial images linked.

2:42

Just scrolling. I don't know if this is folia.

2:44

This is looking pretty good here.

2:46

And just scroll down to the pelvis,

2:48

so you can get a sense of the pre and post contrast appearance of this lesion.

2:58

All right.

3:00

So, let's move on to the question.

3:03

This is going to be question number five,

3:06

is regarding the pelvic mass that I've shown you,

3:09

what is the most likely diagnosis?

3:12

And so,

3:13

the options here,

3:14

urachal adenocarcinoma.

3:16

We talked little bit about that, actually, in our first case.

3:18

So try to remember what the association and where the location should be for that.

3:25

Gastrointestinal stromal tumor.

3:27

Certainly, a possibility can happen in these locations.

3:33

Germ cell tumor as well.

3:34

That's another option I'm presenting to you.

3:37

Solitary fibrous tumor.

3:41

Uncommon tumor.

3:43

But these are challenging cases, at least I think they're challenging.

3:45

So let's see if...

3:48

And I will tell you that based on these images,

3:52

could come with a specific diagnosis.

3:55

All right.

3:56

So I think we're a little bit all over the place.

3:59

This one, we have SFT at the top diagnosis,

4:02

solitary fibrous tumor, gastrointestinal tumor,

4:03

urachal adenocarcinoma, and germ cell tumor is number one.

4:06

Okay. So let's go through this case.

4:08

This was a fun case to go through.

4:11

So, I'll stop the linking.

4:13

So the first thing you notice, the history as I said, you know,

4:16

they got this on this young gentleman, they didn't see a left kidney.

4:20

So the question, is there pelvic kidney?

4:22

Well, if you look at it,

4:23

and it turns out there is a very, very small left kidney.

4:26

It's atrophic.

4:26

I'm not really sure, we didn't have much

4:28

more history on this gentleman that there was a prior insult or something.

4:32

But certainly, my assumption was that this

4:34

is going to be sort of, congenitally, a very small kidney.

4:36

Right kidney, on the other hand, looks very robust, looks very good.

4:40

And as you scroll down all the way here, you'll see the mass and,

4:47

you know

4:47

not much, I think, to be gleaned from the pre and post contrast

4:50

edges except for the fact that it is a mass, that it has enhancement.

4:54

There's soft tissue components to it.

4:57

Perhaps some of it is necrotic or just hypovascular,

5:00

pretty well-defined mass.

5:02

If we look at our options,

5:03

urachal adenocarcinoma was one of them.

5:04

And this is what I want to show you in the sagittal,

5:07

that it really doesn't look like it's arising from the bladder.

5:09

It looks like it almost has some mass effect on the bladder.

5:11

Urachal adenocarcinoma, you'd expect to arise from this tip of the bladder.

5:15

So I think it's a good thing to think about when you see these large

5:18

sort of masses,

5:19

heterogeneous masses, which may be associated with bladder.

5:22

But I think if you were to scroll through this and really look at it

5:26

at your own pace,

5:27

you would see that there's almost a fat plane over here.

5:29

So this is sort of causing mass effect on the bladder.

5:32

So we can sort of knock that one out.

5:34

I think the gastrointestinal stromal tumor is always something

5:36

I think about when I see these masses and I can't quite locate them where they are.

5:40

Solitary fibrous tumors, as well, are rare tumors.

5:43

Something to think about, imaging appearance is often nonspecific.

5:47

What's been described is they are quite vascular on MRI.

5:50

They can have flow voids.

5:52

And classically, they've been associated

5:54

with these perennial plastic syndromes, where they get hypoglycemia

5:58

because the tumor secretes some insulin-like growth factor.

6:02

So, you know, I think those are not bad thoughts,

6:05

but the right answer in this case is actually germ cell tumor.

6:07

So kudos to, I think, the one person who got that right.

6:11

And so, what's the other finding that can

6:12

allow us to make a specific diagnosis here?

6:14

Well, we have this mass, that's not going to help us,

6:16

the appearance itself.

6:17

As you scroll through, what do you notice it's missing over here?

6:21

Right.

6:22

So the left spermatic cord is actually missing in this instance.

6:25

The right spermatic cord is intact, left spermatic cord is missing.

6:28

And so, that tells us that this is a patient who had no other prior surgery.

6:32

Nothing like that.

6:34

May have an undescended testicle somewhere.

6:36

And so, if you were to follow then his testicular vein,

6:41

gonadal veins, you were to see that they would actually

6:45

scroll right into this lesion over here.

6:48

So I want you to follow this vessel right over here,

6:51

going all the way up, going all the way up,

6:54

draining into the left renal vein.

6:56

Now, I didn't expect you to see that,

6:58

obviously, as you're scrolling through it.

7:00

But if we go through it very carefully,

7:01

you can see that this actually germinates right through these masses.

7:05

And so, this turned out to be proven

7:08

mixed germ cell tumor, and somebody who had an undescended testicle.

7:13

And the other cute finding you can see here

7:15

is that his left,

7:16

some of the vesicles either atrophic or just missing.

7:18

And so that probably goes along with some of the other congenital findings that he has,

7:23

a very atrophic left kidney and an undescended left testicle.

7:29

And as you know, cryptorchidism, you know,

7:32

the testicle in those instances can be located anywhere from upstairs

7:36

in the kidney to the inguinal canal, but almost always are included

7:40

in the inguinal canal, about 80% of the times.

7:43

And why do we worry about undescended testicles?

7:46

There is an increased risk of malignancy

7:47

and there's an increased risk of fertility.

7:50

And so, this is one case where relatively

7:53

older gentleman, we see a tumor developing in an undescended testicle.

7:58

All right.

7:59

So that was that case.

8:01

As I said, one of the ones that was

8:05

a relative favorite of mine in the last few years.

8:09

I was happy to share that one with you.

8:10

Lets move on to the next case.