Cotyledonoid dissecting leiomyoma as a possible cause of chronic lower back pain

Uterine fibroids having the distinct pathological and immunohistochemical features of cotyledonoid dissecting leiomyoma have been reported infrequently. We describe a postmenopausal woman with an incidental finding of an abdominopelvic mass arising from the uterine fundus on routine radiological imaging of the lumbar spine. The imaging was performed for the investigation of chronic radicular lower back pain refractory to usual pain management. However, the woman did not manifest any gynaecological symptoms. Intraoperatively, the pelvic mass appeared malignant and a frozen section suggested uterine sarcoma. As such, the mass was radically resected, resulting in significant resolution of the back pain. To the authors' knowledge, this is the first report of cotyledonoid dissecting leiomyoma presenting solely as chronic lower back pain, and also the first report of this fibroid variant in Australasia. We discuss the diagnostic and operative challenges, emphasising the role of radiological imaging and immunohistopathology in such cases and review current literature.