This month is the third and final in a series of cases involving cancer. It involves a cat who was losing weight with no apparent cause, who turned out to have a good reason. It shows how all of the diagnostic techniques we've talked about can be used to diagnose and treat a problem.

GIVE ME THE WORKS...

HISTORY

Winkers was a middle-aged cat who just hadn't been acting right. His appetite had been okay, but he looked unhealthy and had lost a couple of pounds.

PHYSICAL FINDINGS

Winkers didn't like being bothered. He was grumpy and uncooperative, and wouldn't allow much of an exam. However, his belly was obviously uncomfortable, and appeared to contain a large swelling. Our concerns included a urinary obstruction (the lump could have been his bladder), a large abscessed area, or else a growth of some kind. To get a little better idea of what was there, we took x-rays.

TEST RESULTS

Winkers' x-ray confirmed that he had a mass of some kind. It was pushing the intestines out of its way, and had grown to occupy most of his abdomen. (You can also see a pellet, which was probably an old wound and not causing him any problems.) Our primary concern was that the mass was a tumor, but we still had to consider something like an abscess.

Where's the mass?

Winkers' owner consented to surgery. Before going further, we performed pre-surgical blood tests, which all were normal. Also, since we still had to consider an abscess, we performed an ultrasound to determine the internal architecture of the mass.

The ultrasound showed a fairly uniform mass, with some pockets of fluid evident. You can click on the image to the left for a Real Video clip showing the ultrasound (the image is a little blurry - ultrasounds don't translate well to Real media).

TREATMENT

Surgery was performed to remove Winkers' tumor. We found it originating from the outer layers of the intestine, and it weighed nearly 1/2 pound. A few inches of intestine had to be removed, and Winkers was kept on intravenous fluids for a couple of days. He rapidly gained strength and seemed to be recovering well.

The tumor was sent to our lab for a biopsy; we also performed an impression smear for our own information. An impression smear is similar to a needle aspirate in its usefulness, but requires an exposed surface of the tumor (some skin tumors which break open will allow impression smears). The smear has several large abnormal cells visible (the one in the middle has multiple nuclei), suggesting a malignant tumor:

DISCUSSION

Winkers' tumor was identified as a leiomyosarcoma, a malignant tumor arising from smooth muscle tissue. This type of tumor can arise very quickly, but is slow to spread to other organs, and the outlook after surgery is good.

Winkers has done well since surgery. He had some diarrhea after surgery which affected him on and off for a few weeks, but since then has gotten back to normal. He's gained all of his weight back, and four months after surgery there are no signs of any tumor regrowth. And he's grumpy as ever!

see other cases