Oncological outcomes of unexpected uterine leiomyosarcoma: A single-center retrospective analysis of 5528 consecutive hysterectomies

Background and Methods: Uterine leiomyosarcomas (uLMS) are rare malignant tumors, often incidentally discovered, with an estimated annual incidence of five cases per one million women in the United States. This study aimed to compare the oncological outcomes of two groups of patients: those with uLMS incidentally found during surgery and those who underwent surgery due to suspected or confirmed uLMS before the procedure. The study assessed patients who had undergone hysterectomy and were diagnosed with stage I uLMS at a tertiary gynecologic oncology referral center in Italy between January 2000 and December 2019. Data on patients' baseline characteristics, surgical procedures, and oncological outcomes were collected. The patients were classified into two groups based on whether uLMS was unexpectedly discovered or suspected before the surgery. Survival rates and factors influencing recurrence were analyzed. Results: The study included 36 patients meeting the inclusion criteria, with 12 having preoperatively suspected or proven uLMS and 24 having incidentally discovered uLMS. No significant differences were observed between the two groups regarding disease-free survival (23.7 vs. 27.3 months, log rank = 0.28), disease-specific survival (median not reached, log rank = 0.78), or sites of relapse. Notably, among patients who underwent laparoscopic hysterectomy (compared to open surgery), a significantly higher rate of locoregional recurrence was found (78% vs. 33.3%, p = 0.04). Nevertheless, no significant differences in survival were observed based on the surgical approach. Conclusions: Preoperative suspicion for uLMS did not seem to impact survival outcomes or the pattern of recurrence. Furthermore, although patients who underwent laparoscopic hysterectomy showed a higher rate of locoregional relapse, this did not affect their overall survival.