A 65-year-old man consults a physician because he has had severe alternating constipation and diarrhea for the past two months. Hemoccult test on a stool sample is positive for occult blood. Colonoscopy demonstrates a large annular, encircling mass 25 cm above the anal verge, in the descending colon. To which of the following nodes would this tumor be most likely to first metastasize?

This person most likely has an invasive adenocarcinoma of the colon involving the descending colon (a napkin-ring cancer), but above the rectum. The rich lymphatics of the descending colon drain through the mesentery to the inferior mesenteric nodes before draining to the lymphatics and nodes along the aoa. The gastroepiploic nodes drain the greater curvature of the stomach. The internal iliac nodes drain the bladder and male internal genitalia. The sub pyloric nodes drain the distal stomach, pancreas, and duodenum.