Twenty-two cases of appendiceal adenocarcinoma are reviewed. Correct diagnosis was not made preoperatively in any case, and in only 38 per cent of the cases was it made intraoperatively. Thirty-two per cent of the patients had second primary neoplasm, and in more than half of these cases, the neoplasms were most likely concurrent with the appendiceal tumors. The overall five-year survival rate of the 22 patients was 18.7 per cent, with a 43.4 per cent survival rate in the curative resection group. The grade of tumor differentiation was the only significant factor in determining curative resectability and prognosis.