Abstract
BACKGROUND: The use of liquid biopsy of total cell-free DNA (cfDNA) to identify otherwise undetectable cancers has attracted interest; however, its efficacy remains unknown. We explored whether analysis using total cfDNA is efficacious for Japanese patients with oral squamous cell carcinoma (OSCC). METHODS: We collected total cfDNA from nine patients with OSCC preoperatively, 1 month postoperatively, and every 3 months thereafter to analyze this association. We used a target DNA sequence for genetic mutation analysis of tumor tissues collected from 33 patients, including the aforementioned nine patients. RESULTS: Patients with good disease control showed negligible changes in preoperative and postoperative total cfDNA concentrations. A rapid increase in total cfDNA concentration was observed in patients who developed systemic metastases. Patients whose tumor tissue DNA showed genetic mutations had the same mutations in preoperative circulating tumor DNA. CONCLUSIONS: Our data suggested that analyzing total cfDNA is efficacious for patients with OSCC.