[Recurrent multicystic peritoneal mesothelioma in endometriosis of the pelvis].

In the case of a 21-year old woman, who complained of chronic pelvic pain and where cystic structures in the adnexal region had been diagnosed ultrasonically and by laparoscopy, a tumour made up of many small cysts was discovered in the pouch of Douglas next to a typical endometrial cyst. Both the endometrial cyst and the cystic tumour were excised by laparotomy. Histology established the tumour as a multicystic peritoneal mesothelioma. Postoperative recurrence was noticed by ultrasound less than one year later. Laparotomy revealed a 5 cm serous cyst of the right ovary and again countless liquid-filled grape-like small cysts in the pouch of Douglas. Histology revealed a multicystic peritoneal mesothelioma identical to the previously excised tumour. Multicystic peritoneal mesothelioma is a rare soft tissue tumour noted for its frequent recurrences. Most authors agree, that it belongs to the morphological spectrum of reactive mesothelial proliferative lesions and not the neoplastic spectrum. It appears mostly in women, often concomitant with endometriosis and pelvic inflammatory disease and frequently in women, who had previous surgical interventions in the abdominal region.