The Prevalence of Occult Malignancy in Women Undergoing Hysterectomy or Myomectomy for Benign Indications and the Impact of Morcellation on Survival Outcomes: A Meta-Analysis

INTRODUCTION: Uterine fibroids (UFs), also known as leiomyomas, are the most common benign gynecological tumors. Currently, morcellation is discouraged due to the risk of disseminating undetected malignancies. This study aimed to update the prevalence data on occult malignancies in surgeries for suspected benign uterine lesions and analyze the impact of treatment strategies on the survival outcomes in patients with occult malignancy. METHODS: Five English-language literature databases were systematically searched up to July 25, 2024, for studies reporting the incidence of occult malignancies in patients with suspected UFs and their survival outcomes. The study was preregistered on PROSPERO (CRD42024580233). RESULTS: A total of 34 studies were included in the analysis. The pooled incidence of occult malignancies, calculated using a random-effects model, was 2.88 (2.10-3.94) per 1,000 individuals. Significant regional variations were observed in the subgroup comparisons (p < 0.01). Morcellation did not significantly affect progression-free survival (PFS) (hazard ratio [HR]: 1.26, 95% confidence interval [CI]: 0.86-1.84, p = 0.240) or overall survival (OS) (HR: 1.13, 95% CI: 0.70-1.82, p = 0.614). Pooled analysis of HR revealed that chemotherapy significantly improved PFS (HR: 0.49; 95% CI: 0.32-0.77; p = 0.002) and OS (HR: 0.49; 95% CI: 0.28-0.87; p = 0.015). CONCLUSIONS: The incidence of occult malignancies in women undergoing hysterectomy or myomectomy for benign conditions is approximately 2.88 per 1,000 individuals. Morcellation does not impact survival outcomes, whereas adjuvant chemotherapy provides a survival benefit. Further well-designed clinical trials are required to validate these findings.