Utilization and outcomes of fertility-sparing ovarian cystectomy for stage I malignant ovarian germ cell tumors.

OBJECTIVE

Treatment for malignant ovarian germ cell tumors {MOGCTs) in women desiring fertility preservation is typically unilateral salpingo-oophorectomy (USO). While small studies have examined cystectomy for immature teratomas, larger-scale data are limited. We evaluated use and survival outcomes of cystectomy versus USO for stage I MOGCTs.

METHODS

Using the National Cancer Database, we identified women aged 18-49 with stage I MOGCTs who underwent cystectomy or USO from 2004 to 2022. Log-linear regression identified factors associated with cystectomy. Propensity score inverse probability of treatment weighting (IPTW) for average treatment effect on the treated (IPTW-ATT) was applied to estimate the association of cystectomy versus USO with survival using weighted Cox proportional hazards models and Kaplan-Meier curves.

RESULTS

Among 1345 patients, 1194 (88.8 %) underwent USO and 151 (11.2 %) cystectomy. Cystectomy use declined from 18.4 % (2004) to 9.4 % (2022) (P < 0.0001, APC = -5.5 %). Cystectomy was more common in mixed germ cell tumors and at community cancer programs. Patients who underwent cystectomy were less likely to receive lymphadenectomy (21.4 % vs. 35.3 %, SMD = 0.32), while adjuvant chemotherapy use was similar between groups. Adjusted 2-year survival was 99.7 % (USO) vs. 100.0 % (cystectomy), and 5-year survival was 98.7 % (USO) vs. 98.4 % (cystectomy). Adjusted hazard ratio for overall mortality was 0.70 (95 %CI: 0.21-2.33) for cystectomy versus USO. Stratified analyses by histology and age showed no survival differences.

CONCLUSION

Cystectomy use for stage I MOGCT has declined over time. Among patients who underwent cystectomy, estimated overall survival did not differ significantly from that expected of USO, including across histologic subtypes and age.