Risk Factors for Occult Uterine Sarcoma Among Women Undergoing Minimally Invasive Gynecologic Surgery

To determine factors that can identify a population at increased risk for uterine leiomyosarcoma.

Retrospective case-control study (Canadian Task Force classification II-2).

University teaching hospitals.

Seventy-two women who underwent minimally invasive gynecologic surgery for presumed leiomyoma. Patients diagnosed with leiomyosarcoma (cases) were matched with up to 4 controls on age, year of surgery, and surgeon specialty.

Cases were identified through the pathology database, and the diagnosis of leiomyosarcoma or leiomyoma was confirmed by gynecologic pathologists. The cumulative risk of leiomyosarcoma was calculated, and factors predictive of elevated risk for leiomyosarcoma were investigated using conditional logistic regression.

Fifteen patients with the diagnosis of inadvertently morcellated leiomyosarcoma were identified and matched with 57 controls. The cumulative risk of diagnosing uterine leiomyosarcoma on pathology after performing minimally invasive gynecologic surgery with morcellation was 0.19% (95% confidence interval [CI], 0.06%-0.56%). The presence of a hematocrit value < 30% (adjusted odds ratio [aOR], 20; 95% CI, 1.08-100; p = .05) was independently associated with the diagnosis of uterine leiomyosarcoma on multivariate analysis. Increased myoma size (aOR, 9.73; 95% CI, 0.75-1.26; p = .08) and presence of a solitary myoma (aOR, 3.85; 95% CI, 0.65-25; p = .14) were associated with a greater risk of uterine leiomyosarcoma; however, the difference was not statistically significant.

Anemia and myoma size >7 cm may be associated with occult leiomyosarcoma; however, these criteria are not sufficiently discriminatory to allow for preoperative identification of patients with uterine sarcoma. Future large multicenter studies are needed to further investigate these findings and the discovery of innovative ways to detect uterine leiomyosarcoma are urgently needed.