Abstract
Small rectal carcinoids have been detected more frequently with the widespread use of colonoscopy. Most reported rectal carcinoids are less than 20mm in diameter, and the pathological depth of invasion was typically confined to the submucosal layer. However, it is not unusual for these small rectal carcinoids to metastasize to regional lymph nodes and/or to the liver. Here, we report the case of a minute rectal carcinoid, 8mm in diameter, with a huge metastatic obturator lymph node. A 79-year-old woman was hospitalized because of persistent fever and left pretibial edema. Abdominal CT scans demonstrated a large tumor of 13cm in diameter, with intratumoral necrosis occupying the pelvic cavity and compressing the left external iliac vein. With no alternative diagnostic measures available, a percutaneous biopsy was performed and a diagnosis of carcinoid was made. A subsequent colonoscopy revealed a small rectal carcinoid 8mm in diameter and located in the lower rectum to be the primary lesion. We performed a transanal local resection of the primary tumor and simultaneous transabdominal extirpation of the huge pelvic tumor. A pathological examination confirmed that the pelvic tumor was a metastatic obturator lymph node from the rectal carcinoid. No evidence of local recurrence or liver metastasis was seen during the follow-up period. For pelvic tumors of unknown origin, the alimentary tract must be examined to rule out the possibility of metastatic carcinoids.
