AbstractThere is a concern regarding the risk of occult
leiomyosarcomas found at surgery for presumed benign fi-broids. We sought to produce a comprehensive reviewof pub-lished data addressing this issue and provide high-quality prevalence estimates for clinical practice and future research. A comprehensive literature search using the PubMed/ database and the Cochrane Library was per-formed. Inclusion criteria were human studies, peer-reviewed, with original data, involving cases for surgery in which fibroid-related indications were the primary reason for sur-gery, and histopathology was provided. Candidate studies (4864) were found; 3844 were excluded after review of the abstract. The remaining 1020 manuscripts were reviewed in their entirety, and 133 were included in the Bayesian binomial random effect meta-analysis. The estimated rate of leiomyosarcomawas 0.51 per 1000 procedures (95%credible
interval (CrI) 0.16–0.98) or approximately 1 in 2000. Restricting the meta-analysis to the 64 prospective studies
resulted in a substantially lower estimate of 0.12 leiomyosarcomas per 1000 procedures (95 % CrI