One case report of giant atypical leiomyoma of the ovary.

Rationale: Ovarian leiomyoma is a rare ovarian tumor that occurs in 20-65 year-old women, and is mostly misdiagnosed as malignant tumor. In most reports on this type of tumor, ovarian myoma has a benign histology. Herein,we describe a case of ovarian atypical leiomyoma.

Patient Concerns: The patient is a 58-year-old woman. At the age of 40 years old, the patient underwent hysterectomy due to "hysteromyoma" and secondary anemia. The patient was admitted to our hospital due to palpation of lower abdominal mass and abdominal distention.

Diagnoses: A mass was revealed at the left uterine appendage by pelvic ultrasound and CT.Pathology and immunohistochemistry confirmed the diagnosis of the left ovarian atypical leiomyoma.

Interventions: Pelvic cavity resection and right adnexectomy were performed during laparotomy for the patient.

Outcomes: Without radiotherapy or chemotherapy, there were no signs of tumor recurrence in a 9-month follow-up period.

Lessons: When a solid mass appears in ovarian tissues, ovarian leiomyoma should be considered. Patients with this type of tumor are mostly asymptomatic. Preoperative diagnosis was difficult, intraoperative frozen section would be helpful for determining the scope of the surgery, and the correct diagnosis was made by identifying the properties of smooth muscles through postoperative pathology and immunohistochemistry.