Case Study

Colonic and omental hemangiosarcoma in an 11 year old MN DSH cat

This 11-year-old neutered male DSH cat presented for progressive partial anorexia, weight loss, vomiting, and melena. The physical exam revealed moderate dehydration, pale mucous membranes, and a palpable caudal abdominal mass. CBC demonstrated mild regenerative anemia, while the blood chemistry was normal except for moderate lipase elevation.

This 11-year-old neutered male DSH cat presented for progressive partial anorexia, weight loss, vomiting, and melena. The physical exam revealed moderate dehydration, pale mucous membranes, and a palpable caudal abdominal mass. CBC demonstrated mild regenerative anemia, while the blood chemistry was normal except for moderate lipase elevation.

DX

Colonic and omental hemangiosarcoma

Sonographic Differential Diagnosis

Differentials for a mid-abdominal mass are numerous, including neoplasia, granulomatous disease, abscessation, and hematoma formation.

Image Interpretation

The round, well-encapsulated, heteroechoic mass located within the central abdomen contacts the overlying, empty, and contracted descending colon; however, a communication between the two structures is not identified. Closer observation reveals an intact serosal and muscularis layer at the point of contact with the mass (arrow.) Adherence of the mass onto the intestinal wall with hyperechoic reactive omentum is evident (Video 1).

Outcome

The patient responded well postoperatively for approximately 1 month until sudden death occurred at home without warning. Chemotherapy had not been initiated.

Clinical Differential Diagnosis

Neoplasia, GI ulceration, pancreatitis, gastroenteritis, gastrointestinal obstruction, FIP.

Sampling

US-guided fine needle aspirate (22 gauge) samples directly into the hypoechoic portion of the mass where the potentially neoplastic cells usually are located was conducted (Video 2). Note that the sample is taken from jabs in separate directions within the target to ensure that a variety of cells is obtained. Cytology revealed mixed inflammation with pleomorphic spindle cells. Surgical resection revealed colonic/omental hemangiosarcoma.