Survival outcomes and treatment patterns in malignant ovarian sex cord-stromal tumors: A population-based analysis

This study aimed to evaluate treatment patterns and survival outcomes by histologic subtype and stage in malignant ovarian sex cord-stromal tumors (SCSTs), focusing on the impact of adjuvant chemotherapy to inform histology-specific treatment strategies.

This retrospective cohort study identified adult patients newly diagnosed with malignant ovarian SCSTs using nationwide claims data from Korea (2012-2019). Patients were classified into granulosa-type and other subtypes. Treatment patterns, including upfront cytoreductive surgery and adjuvant chemotherapy, were described. Overall survival (OS) and time to first subsequent therapy or death (TFST) were estimated using Kaplan-Meier methods and compared across subgroups. In localized-stage patients undergoing upfront surgery, the association between adjuvant chemotherapy and survival outcomes was further evaluated. Sensitivity and landmark analyses assessed the robustness of findings.

Among 314 patients (256 granulosa-type and 58 non-granulosa), localized disease was more common in both groups (granulosa-type: 68.4 %, non-granulosa: 67.2 %). Most patients received upfront cytoreductive surgery (granulosa-type: 88.7 %, non-granulosa: 89.7 %, overall: 88.9 %), while adjuvant chemotherapy was more commonly administered in non-granulosa tumors. In the localized-stage subgroup, adjuvant chemotherapy was associated with longer TFST in non-granulosa SCSTs (5-year TFST: 94.1 % vs. 61.9 %), whereas no significant benefit was observed in granulosa-type tumors. OS remained high (>85 %) across all histologic subtypes and treatment.

This study supports upfront cytoreductive surgery as the primary treatment for ovarian SCSTs and suggests the role of adjuvant chemotherapy should be guided by histologic subtype. These findings support histology-driven treatment strategies and the need for prospective studies to optimize individualized management.