<prompt> Most common primary malignant neoplasm of small bowelAdenocarcinomaCarcinoidGISTLymphoma  <response>: Ans a Adenocarcinoma Ref: Sabiston 18th ed pg 1312 1. MC tumor of the small bowel is ADENOMAGIST. 2 MC symptomatic tumor of the small bowel is GIST. 3. MC MALIGNANCY of the small bowel is Mets. 4.MC PRIMARY malignancy of the small bowel is ADENOCARCINOMA Adenocarcinoma - 50 malignant tumors of small bowel - 7th decade of life; male predominance - Duodenum proximal jejunum - Those assosciated with crohns disease present in younger age 70 in ileum - Tumors in duodenum - cc bleeding, jaundice - Tumors in jejunum ileum- pain, weight loss, intestinal obstruction cc bleeds Treatment Wide resection including regional lymph nodes. For duodenal tumors - Whipples resection. 