Mutational landscape of Japanese patients with oral squamous cell carcinoma from comprehensive genomic profiling tests.

OBJECTIVES: Oral squamous cell carcinoma (OSCC) is the most common subtype of head and neck squamous cell carcinoma (HNSCC). Treatment options for OSCC are currently limited owing to the lack of identified therapeutic targets. In this study, we aimed to analyze the genomic profiles of Japanese patients with OSCC and compare them to those of patients with HNSCC to identify potential therapeutic targets. MATERIALS AND METHODS: We extracted the clinical and genomic information of patients with OSCC (n = 242) and those with other HNSCC (n = 402) who underwent comprehensive genomic profiling tests under the National Health Insurance between June 2019 and April 2024 from the Center for Cancer Genomics and Therapeutics database. RESULTS: The most frequent genomic alterations identified in OSCC were TP53 (85.5 %), followed by TERT (62.4 %), CDKN2A (41.3 %), FGF19 (24.9 %), and CCND1 (23.6 %). FGF19 and CCND1 were co-amplified, and CDKN2A and CDKN2B were co-deleted. The frequencies of TERT, HRAS, and CASP8 alterations were the highest in OSCC among all HNSCC subtypes. The frequency of EGFR alterations was substantially higher in adolescent and young adults than older patients with OSCC. Genes associated with genomic integrity and the RTK-RAS pathway were frequently altered in OSCC. CONCLUSION: This study analyzed the genomic profiles of patients with OSCC in Japan and the genetic differences between OSCC and other HNSCC subtypes. This analysis offers insights into the development of personalized therapeutics for OSCC.