Intestinal Myxoid Leiomyosarcoma in a Sambar Deer (Rusa unicolor)

A 9-year-old male sambar deer (Rusa unicolor) that died during sedation had a large and firm polypoid mass, which expanded the small intestinal wall and partially obstructed the duodenal lumen. Histopathology revealed a pleomorphic sarcoma composed of stellate to spindloid cells loosely arranged in an abundant myxoid matrix. The cytoplasm of the neoplastic cells was strongly immunopositive for vimentin and smooth muscle actin, but negative for c-KIT, desmin and myoglobin. The findings are consistent with intestinal myxoid leiomyosarcoma, which is rare in cervids and has not been described in the sambar deer, which is an endangered species.