PURPOSE:Adenocarcinoma of the appendix is a rare neoplasm, and controversies persist regarding management. The purpose of this study was to identify prognostic factors and define management strategies for patients with adenocarcinoma of the appendix.METHODS:A retrospective case series was conducted at three medical school teaching hospitals over a 20‐year period from 1972 to 1992. Overall survival was determined by the actuarial life table method. Comparisons of prognostic factors were made using exact nonparametric log‐rank tests.RESULTS:Thirteen patients were diagnosed during the study period. Median age was 62 years. There were five males and eight females. The disease swas not suspected in any patient preoperatively. Seventyseven percent of patients had metastatic disease at presentation. Second primary malignancies were found in 15 percent of patients. Thirty‐eight percent of female patients had synchronous ovarian lesions. Median survival was 22 months, with an estimated five‐year survival of 43 percent (95 percent confidence interval, 22‐84 percent). Patients with colonic histology had significantly worse survival than patients with mucinous histology (tP=0.0093). Patients with carcinomatosis had a significantly worse survival than noncarcinomatosis patients (tP=0.0078). Patients who underwent right hemicolectomy had a better prognosis for survival than appendectomy patients, but the difference was not statistically significant.CONCLUSIONS:Carcinoma of the appendix is very difficult to diagnose preoperatively, and most patients are not identified until disease is advanced. Good prognostic factors include mucinous histology and the absence of carcinomatosis. Right hemicolectomy appears to be a reasonable option, although its superiority to appendectomy alone has not been definitively proven. High frequency of ovarian metastases in women suggests a role for bilateral oophorectomy. In addition, a complete work‐up of the patient for a synchronous malignancy, especially in the gastrointestinal tract, should be considered.