ULTRASONOGRAPHIC DIAGNOSIS OF GASTROINTESTINAL SMOOTH-MUSCLE TUMORS LN THE DOG

Historical, physical examination, clinicopathologic, radiographic and ultrasonographic findings of 13 dogs with gastrointestinal (GI) smooth muscle tumors (11 leiomyosarcomas, 2 leiomyomas) were reviewed. Histo ry, including signalment and chief complaint, physical examination and bloodwork were neither sensitive nor specific for GI neoplasia. Imagi ng procedures, radiology and ultrasonography, detected the presence of abdominal masses in 12 patients, including 9 animals lacking a palpab le mass on initial examination. Survey radiographs of 10 of the 13 dog s revealed a mass effect in 5/10 dogs, evidence of peritoneal effusion or free abdominal gas in 3/10 dogs, and an obstructive pattern with g as and fluid distension of the intestinal tract in 1/10 dogs. Ultrason ography identified an abdominal mass in 12/13 dogs, and peritoneal eff usion in 5 animals. Ultrasonography correctly recognized an associatio n of the mass with bowel segments by the presence of intraluminal gas, within or adjacent to the mass effect, in 10 dogs, and strongly sugge sted an intestinal origin in one additional animal. GI smooth muscle t umors often appeared as large masses, eccentrically projecting from th e bower wall, frequently containing single or multiple hypo/anechoic r egions. Based on this study we conclude that ultrasonography is more s ensitive than survey radiography in the detection of GI smooth muscle tumors, and may present specific features to distinguish smooth muscle tumors from other types of GI tumors. Ultrasonography is recommended as a screening procedure for cases where GI neoplasia is suspected.