Leiomyomatosis peritonealis disseminata: does malignant transformation occur? A literature review

Leiomyomatosis peritonealis disseminata (LPD) is a rare smooth muscle tumor. In the literature more than 100 cases have been described. LPD is characterized by multiple small nodules on the peritoneal surface, mimicking a malignant process with metastases, but generally demonstrates benign histologic features. Exposure to estrogen seems to play an etiologic role. Many patients have uterine leiomyomas as well. The diagnosis of LPD is easily made on biopsy. Reduction of estrogen exposure is generally sufficient to cause regression of LPD. Surgical castration or gonadotrophin releasing hormone agonists seem good alternatives in the case of progression or recurrence of LPD. In six patients a malignant leiomyosarcoma has been described shortly after the diagnosis of LPD was made. Five of these patients did not have uterine leiomyomas or exposure to exogenous or increased endogenous estrogen. The relationship with pregnancy in the sixth patient may be coincidental. Whether malignant transformation of LPD occurs remains uncertain. Characteristics of these patients differ from those of LPD patients and may indicate a high malignant potential, necessitating a different approach.