BENIGN RETROPERITONEAL CYSTS OF MULLERIAN TYPE - A CLINICOPATHOLOGICAL STUDY OF 3 CASES AND REVIEW OF THE LITERATURE

Benign retroperitoneal cysts (RPCs) of mullerian type may present as a pelvic mass in a perimenopausal or postmenopausal woman, and thus cli nically can mimic an ovarian malignancy. We report three women, aged 7 3, 45, and 68 years, who presented with large RPC masses ranging from 8 to 17 cm in diameter. Histologically, the cysts were lined by benign mullerian-type epithelium: serous epithelium in two patients and muci nous epithelium in one patient. A malignant component was. not present in any of the cases. Preoperative diagnosis in two patients was ovari an carcinoma based on clinical and computerized tomography findings: T wo patients are alive without evidence of disease 44 and 56 months fol lowing surgical excision, whereas one patient died of perioperative co mplications unrelated to the cystic lesion. Similar previously reporte d cases and their possible pathogenetic mechanisms are discussed. Alth ough the mullerian type of RPCs behave in a benign manner, a malignant component has to be searched for. Thus, complete excision with carefu l histologic examination rather than drainage or marsupialization is r ecommended.