LAUSR

Background Uterine leiomyoma is the most common benign tumor in women. Uterine sarcoma, though with very low incidence, has a high malignant degree and poor prognosis. It has difficulties in preoperative diagnosis, frozen pathological examination and postoperative treatment. Case report A 49-year-old woman presented with menstrual disorder. Magnetic resonance imaging showed a huge uterine mass. The patient underwent laparoscopic hysterectomy and part of the uterine tissue looked like fish. Specimens were sent to frozen pathological examination for four times, but none of the results showed malignancy certainly. Considering all abnormalities, we removed the uterine through vagina completely rather than morcellation and did pelvic lymph node biopsy. Postoperative pathological examination revealed uterine leiomyosarcoma and one pelvic lymph node had metastasized. Conclusion Uterine sarcoma is difficult to be diagnosed even frozen pathological examination has been performed. Unexpected uterine sarcoma should always be considered, and precautions should be taken if we find anything suspicious. Fortunately, the patient has avoided second operation.