Landscape of genomic alterations and clinical outcomes in low-grade serous ovarian cancer in Korea

Abstract

Introduction

To investigate the clinical characteristics, molecular findings, and survival outcomes of patients with low-grade serous ovarian cancer in Korea, with a focus on addressing the limited data on genetic profiling and targeted therapies in Asian populations.

Methods

This study is a retrospective review of patients with pathologically confirmed LGSOC treated at the National Cancer Center Korea between 2010 and 2023. Patients underwent cytoreductive surgery and/or systemic or hormonal therapy. Molecular profiling included next-generation sequencing (NGS) of formalin-fixed, paraffin-embedded tumor samples and homologous recombination deficiency (HRD) testing. Survival outcomes were assessed using Kaplan–Meier analysis.

Results

A total of 62 patients were included, with a median age of 41 years; 61.3 % presented with advanced-stage disease. BRCA mutations were detected in 6.4 % (BRCA1: 4.8 %, BRCA2: 1.6 %). MAPK pathway alterations were identified in KRAS (11.3 %), BRAF (9.7 %), NF1 (3.7 %), and NRAS (1.2 %). Among BRAF mutations, 66.7 % were V600E, while KRAS mutations predominantly involved codon 12. ER and PR were positive in 88.7 % and 66.1 % of cases, respectively. With a median follow-up of 47.5 months, the median progression-free survival (PFS) was 169.3 months (95 % CI: 60.6–NA).

Conclusion

This study identifies frequent MAPK pathway mutations, including KRAS and BRAF, and a prevalence of BRCA1/2 mutations in low-grade serous ovarian cancer. Compared to Western cohorts, KRAS and BRAF mutations were observed at relatively lower frequencies, highlighting potential regional differences in the molecular landscape of low-grade serous ovarian cancer.