When the uterine mass is not a leiomyoma

A 37-year-old nulliparous woman with abnormal uterine bleeding and a uterine mass suggestive of a leiomyoma not responding to medical therapy was submitted to two hysteroscopies with histological analysis. The first one showed a 'leiomyoma' and the second a 'uterine smooth muscle tumour of uncertain malignant potential/epithelioid leiomyosarcoma, with positivity for hormonal receptors'. The patient was submitted to a total hysterectomy with bilateral salpingo-oophorectomy, and the microscopic examination of the tumour revealed a 'uterine tumour resembling ovarian sex-cord tumours'. According to the literature, most cases are diagnosed in postmenopausal women and have a favourable prognosis. These rare tumours have uncertain malignant potential and have no established treatment protocol, but it appears that a fertility-sparing approach is possible once they are well diagnosed.