Regional Differences in Genetic Profiles of Uterine Cervical Cancer in Okinawa, Japan

Background/Objectives: Regional differences in genomic mutation profiles of uterine cervical cancer have been reported. Japanese people are divided into two genetic background clusters, originating from mainland Japan and Okinawa. No studies have examined gene mutation profiles of cervical cancer in Okinawa. This study aimed to investigate the mutation profile of cervical cancer in Okinawa in addition to predictive genetic mutations for prognosis after definitive radiotherapy for cervical cancer. Methods: Twenty-three patients with biopsy-proven squamous cell carcinoma and adenocarcinoma of the intact uterine cervix who were treated with definitive radiotherapy were analyzed. Genomic DNA was extracted from fresh frozen tissue samples collected by tumor biopsy prior to treatment. Variants of 224 cancer-related genes were identified using next-generation sequencing. Genetic mutations were identified and their associations with clinical outcomes were examined. Results: A total of 29 gene mutations were observed in 16 patients, including nine recurrent mutations: SCN7A (17%), PIK3CA (13%), FGFR4 (13%), USP6 (13%), SETD2 (9%), KIT (9%), TSC1 (9%), SERPING1 (9%), and NOTCH3 (9%). Significant mutations in ARID1A, FBXW7, PTEN, TP53, and EP300, reported as relatively common in cervical cancer in other regions were not detected. The rate of 2-year overall survival and progression-free survival was 95.5% and 73.4%, respectively. No significant differences were observed between gene mutations and either survival. Conclusions: The findings indicate that the gene mutation profiles of cervical cancer in Okinawa may differ from those in other regions. Genetic mutations were not identified as significant prognostic factors after definitive radiotherapy.