Mucinous cystadenocarcinoma of the appendix. The controversy persists: a review.

Mucinous cystic neoplasms of the appendix continue to engender considerable debate in their diagnosis, management, and role in pseudomyxoma peritonei. This review addresses ongoing controversies with these unique neoplasms. Case reports and institutional series of mucinous cystadenocarcinoma were retrieved from the literature using Medline Search (1985-1996) using the following key words: appendix; mucinous cystadenocarcinoma; pseudomyxoma peritonei. 284 patients with mucinous cystadenocarcinoma were identified. Abdominal pain was the most common presenting symptom and objective preoperative diagnosis was difficult. There were 22 patients with concomitant appendiceal and ovarian mucinous neoplasms. Sixty-seven patients presented with mucinous cystadenocarcinoma and pseudomyxoma peritonei. However, a unified definition of pseudomyxoma peritonei was lacking. The recurrence rate was higher when an appendiceal neoplasm was associated with pseudomyxoma peritonei. In the reported literature, about an equal number of patients were subjected to appendectomy alone or right hemicolectomy. However, there was a survival advantage for right hemicolectomy versus appendectomy alone. Management of disseminated pseudomyxoma peritonei remains controversial. Mucinous cystadenocarcinoma appears to be a spectrum of low-grade malignant tumors. For correct diagnosis, a high index of suspicion must be maintained. The appropriate treatment for a patient with mucinous cystadenocarcinoma should be a right hemicolectomy. Aggressive debulking may improve survival when associated with pseudomyxoma peritonei. A better definition of pseudomyxoma peritonei is needed. In evaluation of different treatment modalities and prognosis, patients should be grouped according to underlying primary pathology.