A retrospective review of the files of 1,740 appendectomies performed during a 10-year period disclosed 13 patients (0.7%) with primary appendiceal tumors. Adenocarcinoma of the appendix was diagnosed in 6 patients (0.3%), which is a two- to four-fold higher incidence than reported in the literature. The other seven patients had benign tumors and only appendectomy was performed. The female to male ratio of adenocarcinoma was 5:1. All six adenocarcinoma patients, classified histologically as Dukes' B stage, underwent right hemicolectomy, and were disease free following a mean follow-up of 35 months. The results of our policy, also recommended by others, confirmed the benefit of right hemicolectomy in all patients with confirmed primary appendiceal carcinomas.