“Benign” Rectal Carcinoids: A Report of Two Patients with Metastases to Regional Lymph Nodes

Abstract

A rectal carcinoid is usually considered benign if it is clinically or histologically less than 2 cm. in diameter and neither is fixed to, nor has invaded, the muscularis propria. From a series of 35 rectal carcinoids evaluated by these criteria, 29 were classified as “benign.” None of these 29 patients has shown progressive disease. Two patients with “benign” rectal carcinoids had unsuspected metastases to regional lymph nodes. Evidence from our material indicates that the use of the term “benign” to qualify a rectal carcinoid is relative and occasionally may be inaccurate. Evidence from the clinical material which has accumulated in the literature indicates that local excision of a “benign” rectal carcinoid is seldom, if ever, followed by progressive disease. Since it is unlikely that our two patients are the only examples of “benign” rectal carcinoid with metastases, it is postulated that following excision of a “benign” rectal carcinoid, regional metastases may cease to grow and remain latent, or they may spontaneously regress.