Senior cat with large intestinal mass and hyperechoic mesentery: peritonitis? carcinomatosis?

Senior cat with large intestinal mass and hyperechoic mesentery: peritonitis? carcinomatosis?

Senior cat with large intestinal mass and hyperechoic mesentery: peritonitis? carcinomatosis? * 13 yo cat, weight loss, mild decrease in appetite, large abdomen. No fever. * Leukocytosis (WBC 27) with neutrophilia 22251), monocytosis (3846), low albumin (2.2), low TP (4.8), mild increase of ALP (84).  * Large (5.5cm long by 3cm wide) heterogeneous hypoechoic intestinal…