Epithelial-Mesenchymal Transition with Malignant Transformation Leading Multiple Metastasis from Disseminated Peritoneal Leiomyomatosis.

Disseminated peritoneal leiomyomatosis (DPL) is a rare condition that is characterized by the presence of multiple subperitoneal or peritoneal smooth muscle nodules of varying sizes on the omentum and peritoneal surfaces, grossly mimicking disseminated carcinoma. DPL usually develops in premenopausal women with a benign course, and it is often found incidentally during abdominal surgery. Malignant transformation is a rare clinical course of DPL. Only a few studies have focused on DPL transformation into a leiomyosarcoma. Herein, we describe the case of a 61-year-old woman with a history of recurrent leiomyoma of the uterus who presented with intermittent progressive abdominal pain. The imaging study revealed a huge heterogeneous density mass in the pelvic region with pulmonary and hepatic metastases. Exploratory laparotomy and debulking surgery were performed, and showed the coexistence of DPL and leiomyosarcoma. She died approximately one month after the diagnosis because of rapid progression of pleural effusion due to malignancy. This case highlights the clinical features of DPL and its malignant transformation and metastasis so physicians can make an early diagnosis and provide timely management.