Smooth muscle tumor of uncertain malignant potential (STUMP): a clinicopathologic analysis of 26 cases.

BackgroundTo investigate the clinicopathologic features, differential diagnosis, and factors associated with recurrence in patients with smooth muscle tumors of uncertain malignant potential (STUMP).MethodsThe clinical and pathologic data of STUMP patients diagnosed in Mindong Hospital of Ningde City from 2017 to 2018 were collected and slides reviewed, the high-frequency color Doppler ultrasound and pathological characteristics were observed, and the literature was reviewed.ResultsAll the STUMP diagnoses were confirmed by slide review. The age of onset was 23-61 years (mean 42.96 years). The main clinical symptoms were leiomyoma of uterus, prolonged menstruation, and increased menstruation. Color Doppler ultrasonography showed hypoechoic uterine wall nodules. The mean follow-up time was 62.9 months (range: 13-96 months).ConclusionsSmooth muscle tumors of undetermined malignant potential (STUMP) in the uterus are one of the rare gynecologic neoplasms. Although not malignant, they should be considered as low malignant potential tumors because they occasionally recur. Six of 13 recurrent tumors recurred in the years following hysterectomy with preservation. These six recurrent tumors are the only ones that had a strong immune response to p16 and p53. In support of early observation, these markers may help predict STUMP behavior. Patients diagnosed with STUMP should be monitored over time.