Primary, papillary peritoneal neoplasia.

Subsequent to the recognition of the intraperitoneal tumors of low malignant potential, clinicians have repeatedly faced the ambiguities inherent in a disease that seems aggressive on the basis of its wide distribution in the peritoneal cavity but benign on the basis of its histopathology and clinical course. Whereas the occasional case has been associated with extensive local reaction and ascites, except for a rare exception these tumors result in prolonged survival and in an absence of extraabdominal extension. The current review of 154 cases followed from 2 to 40 years, performed in an attempt to understand this perplexing disease, leads to the following conclusions: 1) Whereas frequently beginning on the ovary and showing a predilection for the pelvis, there are examples of widely disseminated peritoneal disease with minimal, if any, ovarian involvement; 2) the outcome without adjunctive therapy is excellent and thus such therapy is contraindicated in view of the death of only 2 of the 154 patients with disease, 1 of whom had had adjunctive intraperitoneal isotope therapy; and 3) this disease is best understood as a diffuse primary peritoneal tumor probably developing on the basis of irritating agents' reaching the abdominal cavity from the lower genital canal, a process similar to that proposed for the genesis of endometriosis. Such a low-grade primary in situ tumor that may involve the entire peritoneal cavity is compatible with prolonged survival.