Uterine smooth muscle tumours with uncertain malignant potential: reproductive and clinical outcomes in patients undergoing fertility-sparing management

STUDY QUESTION: Can patients with uterine smooth muscle tumours of uncertain malignant potential (STUMP) be effectively and safely managed with fertility-sparing treatment? SUMMARY ANSWER: This multicentre retrospective study demonstrates that fertility-sparing management for patients diagnosed with STUMP is both feasible and safe. WHAT IS KNOWN ALREADY: Few studies, involving a limited number of patients, have investigated fertility-sparing management for STUMP in women with future pregnancy aspirations. STUDY DESIGN, SIZE, DURATION: This multicentre retrospective study was conducted in collaboration with 13 Italian institutions specializing in gynaecologic oncology. The primary objective was to evaluate the reproductive outcomes of the included patients, while the secondary objective was to analyse their clinical outcomes. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 106 patients with a histological diagnosis of STUMP who underwent fertility-sparing treatment for uterine tumours were included. Patient data were collected from 13 referral centres across Italy, and reproductive and clinical outcomes were documented during follow-up. The median (range) length of follow-up was 48 (7–191) months. MAIN RESULTS AND THE ROLE OF CHANCE: Of the 106 patients, 47 (44.3%) patients actively tried to conceive after fertility-sparing surgery, and 27 of them (57.4%) achieved a pregnancy. Among the patients trying to conceive, 12 (25.5%) women had more than one pregnancy after surgery for STUMP. At follow-up, 23 (21.7%) out of the 106 women had a recurrence of uterine disease. Furthermore, a higher rate of recurrence was observed among patients who became pregnant (17 out of 27 women (63.0%)) compared with those who did not (6 out of 79 women (7.6%); P < 0.001). Only two cases (1.9%) of malignant relapse were recorded, and one patient with a leiomyosarcoma recurrence died. LIMITATIONS, REASONS FOR CAUTION: The primary limitation of this study is the inherent biases associated with its retrospective design. WIDER IMPLICATIONS OF THE FINDINGS: This multicentre retrospective study represents the largest case series to date examining the reproductive and clinical outcomes of patients undergoing conservative treatment for STUMP. The findings suggest that patients can be counselled on the feasibility and safety of fertility-sparing management, which should be considered by clinicians as both safe and effective.