Case Study

Colonic mass in a 14 year old FS DSH cat

A 14-year-old FS DSH cat was presented for the evaluation of anorexia, diarrhea and rectal bleeding. The cat also had a 2-year history of obstipation for which she was receiving lactulose on a regular basis, as well as a grade III/VI systolic murmur and renal disease. Blood chemistry and CBC were unremarkable. T4 was within the normal reference range.

A 14-year-old FS DSH cat was presented for the evaluation of anorexia, diarrhea and rectal bleeding. The cat also had a 2-year history of obstipation for which she was receiving lactulose on a regular basis, as well as a grade III/VI systolic murmur and renal disease. Blood chemistry and CBC were unremarkable. T4 was within the normal reference range.

DX

Colonic mass

Sonographic Differential Diagnosis

Distal obstructive colonic mass effect: neoplastic or inflammatory. Most common neoplastic differentials include lymphoma, mast cell, and adenocarcinoma. Other less likely differentials: fibrosarcoma, undifferentiated sarcoma, leiomyoma, leiomyosarcoma, plasmacytoma, and neuroendocrine carcinoma.

Image Interpretation

Video 1: Colon appears thickened and obstructed due to a 3cm annular irregular distal descending colonic mass in the pelvic inlet. Note pelvic shadow on right of the video clip. Image and video 2: Colonic mass effect and mural vascular pattern evidenced by power Doppler.

Outcome

Patient was euthanized.

Comments

The last 2 cm of the colon could not be visualized as normal indicating surgical resection was unlikely to be effective. Further diagnostics were declined.

Clinical Differential Diagnosis

GI pathology (neoplasia -lymphoma, adenocarcinoma, leiomyoma, leiomyosarcoma, mast cell tumor; inflammatory bowel disease (less likely,) polyp, granuloma, abscess, colitis; Peritonitis secondary to an obstruction caused by one of the above; Pancreatic pathology (pancreatitis with secondary colitis); Renal pathology (progression of the renal insufficiency).