Question : A 50 year old lady presented to casualty with acute abdominal pain in periumblical area and features s/o intestinal obstruction . A CECT of abdomen showed a mass lesion in transverse colon with thickening of colonic wall from descending colon to hepatic flexure. A colonoscopy was performed
within 24 hrs and the the mass lesion was visualized in transverse colon obstructing the lumen. A biopsy was taken. What is the diagnosis ?