Disseminated peritoneal leiomyomatosis: A case report.

This report describes the case of a patient in her early 40s with a history of laparoscopic myomectomy who presented to the Beijing Shunyi District Maternal and Child Health Hospital (Beijing, China) in December 2024 with menstrual disturbances and a pelvic mass. The patient had disseminated peritoneal leiomyomatosis, a rare benign neoplastic condition characterized by multifocal smooth muscle nodules on the peritoneal surface. Its nonspecific clinical and radiological features often lead to misdiagnosis as malignant peritoneal carcinomatosis. Pelvic magnetic resonance imaging revealed a 9.5-cm cervical mass, an 11.4-cm right pelvic mass, and multiple T2-hypointense uterine lesions, with the largest lesion measuring 14.9 cm. The patient underwent a total laparoscopic hysterectomy with bilateral salpingectomy and resection of multiple mesenteric tumors, with an aggregate specimen weight of 4600 g. Histopathological examination confirmed benign leiomyomatosis, thereby establishing the diagnosis of disseminated peritoneal leiomyomatosis. This case demonstrates a causal link between uncontained morcellation and disseminated peritoneal leiomyomatosis, underscores the role of magnetic resonance imaging T2 hypointensity in differentiating this benign condition from malignancies such as leiomyosarcoma, and confirms surgery as the cornerstone of management when fertility is not a concern. Long-term surveillance remains imperative due to risks of recurrence and rare sarcomatous transformation. Written informed consent was obtained from the patient for treatment and publication, and all patients details have been deidentified to protect anonymity.