Fertility-sparing vs hysterectomy for uterine STUMP: A pragmatic clinical study

Background Uterine smooth muscle tumors of uncertain malignant potential (STUMP) are rare neoplasms with unpredictable clinical behavior. Optimal management, particularly in reproductive-aged women, remains controversial, with limited data comparing the safety of fertility-sparing versus hysterectomy. Methods This multicentre retrospective cohort study included women aged 18–85 with histologically confirmed STUMP treated at 17 Italian gynecologic oncology centers from 2010 to 2023. Patients underwent either fertility-sparing surgery (myomectomy or hysteroscopic resection) or definitive surgery (hysterectomy ± salpingo-oophorectomy). Kaplan–Meier and Cox models were used to compare recurrence-free survival (RFS) and overall survival (OS). Results Median (range) follow-up was 51 (1−291) months. Among 401 women, 106 (26.4 %) received fertility-sparing treatment (mean [± SD] age: 35.3 ± 6.8 years) and 295 (73.6 %) underwent definitive surgery (mean [± SD] age: 47.7 ± 9.2). At total follow-up, recurrence occurred in 12.5 % of patients, predominantly within the pelvis. Median RFS was longer after definitive surgery than after fertility-sparing procedures (50.0 vs 42.5 months; HR 2.39 [95 % CI 1.36–4.19]), although this difference disappeared when benign (leiomyoma) recurrences were excluded (HR 1.74 [95 % CI 0.90–3.34]). At last available follow-up, 97.5 % of patients were alive, with no significant OS difference between treatment groups (HR 0.22 [95 % CI 0.27–1.79]). Outcomes were comparable across menopausal status and concurrent adnexal removal. Conclusion Definitive surgery reduces recurrence risk, but long-term survival is similarly excellent after fertility-sparing surgery in appropriately selected women with STUMP. Conservative management represents a reasonable option for patients desiring fertility, provided they receive counseling regarding recurrence risk, diagnostic uncertainty, and the need for long-term surveillance.