Endometriosis-associated intestinal tumors: a clinical and pathological study of 6 cases with a review of the literature.

This clinicopathologic study of primary Mullerian tumors of the bowel arising in foci of endometriosis is based on six new cases and an analysis of 17 previously reported cases. Varieties of Mullerian tumors occur in the bowel; the most common types are endometrioid carcinoma, followed by various mixed Mullerian tumors and stromal sarcomas. Seventy-eight percent develop in the rectosigmoid colon, the remaining in the cecum or ileum. Those in the latter area tend to be sarcomas or mixed Mullerian tumors. Certain architectural growth characteristics, derived from precursor endometriosis, are common to most endometriosis-associated intestinal tumors (EAITs). Seventy percent of EAITs occur in the outer bowel wall. Transmural tumors tend to form luminal polyps and assume an hourglass shape. Metachronous or synchronous Mullerian tumors occur in 39% of cases. Seventy percent of women with EAITs are in their mid 30s to early 50s. Common presenting symptoms are abdominal or pelvic pain, melena, and an abdominal or pelvic mass. Documented in 26% of patients is a history of prolonged unopposed estrogen therapy. Only 28.5% of cases die of their tumors, but follow-up is less than 5 years in all but 2 patients.