Lipoleiomyoma: a potential mimic of an ovarian dermoid cyst on MRI—a case report

Abstract

Uterine lipoleiomyomas are rare variants of uterine leiomyomas which is composed of adipocytes and smooth muscle cells. In this report, we describe the case of a 39-year-old patient who presented with persistent, isolated pelvic pain. Ultrasonography showed an oval, well-defined left ovarian mass. Computed tomography (CT) scanning showed a predominantly-fatty mass with tissular components, no calcifications and heterogeneously enhanced after injection, suggesting initially a mature teratoma. Magnetic resonance imaging (MRI) findings revealed a latero-uterine mass, suggesting the presence of a left ovarian dermoid cyst with a potentially-malignant fleshy component. A subsequent pathology report revealed a lipoleiomyoma with cartilaginous metaplasia. Most notably, despite the fatty nature of the tumour and the use of MRI, the pedunculated appearance of the lipoleiomyoma observed intraoperatively mimicked a dermoid tumour even on imaging. Improved understanding of leiomyoma variants and secondary degenerative changes can help prevent misdiagnosis.