The distribution of regional lymph node metastases in carcinomas of the cecum, ascending colon, and transverse colon follows the vascular distribution in the ileocolic mesentery, ascending mesocolon, and transverse mesocolon. The location of these metastatic nodes can be recognized on CT scans when the anatomy of the vessels in the ileocolic mesentery and mesocolon is well understood. This knowledge is important in the preoperative staging of carcinomas of the colon for curative surgery and in the early detection of recurrent nodal disease after curative surgery.