The mutational landscape of recurrent versus nonrecurrent human papillomavirus-related oropharyngeal cancer.

Background: Human papillomavirus-related (HPV-related) oropharyngeal squamous cell carcinomas (OPSCCs) have an excellent response rate to platinum-based chemoradiotherapy. Genomic differences between primary HPV-related OPSCCs that do or do not recur are unknown. Furthermore, it is unclear if HPV-related OPSCCs that recur share a genomic landscape with HPV-negative head and neck cancers (HNCs).

Methods: We utilized whole exome sequencing to analyze somatic nucleotide (SNVs) and copy number variants (CNVs) among a unique set of 51 primary HPV-related OPSCCs, including 35 that did not recur and 16 that recurred. We evaluated 12 metachronous recurrent OPSCCs (7 with paired primary OPSCCs) and 33 primary HPV-unrelated oral cavity and OPSCCs.

Results: KMT2D was the most frequently mutated gene among primary HPV-related OPSCCs (n = 51; 14%) and among metachronous recurrent OPSCCs (n = 12; 42%). Primary HPV-related OPSCCs that recurred shared a genomic landscape with primary HPV-related OPSCCs that did not recur. However, TSC2, BRIP1, NBN, and NFE2L2 mutations occurred in primary OPSCCs that recurred but not in those that did not recur. Moreover, primary HPV-related OPSCCs that recur harbor features of HPV-unrelated HNCs, notably including MAPK, JAK/STAT, and differentiation signaling pathway aberrations. Metachronous recurrent OPSCCs shared a genomic landscape with HPV-unrelated HNCs, including a high frequency of TP53, CASP8, FAT1, HLA-A, AJUBA, and NSD1 genomic alterations.

Conclusion: Overall, primary HPV-related OPSCCs that recur share a genomic landscape with nonrecurrent OPSCCs. Metachronous recurrent OPSCCs share genomic features with HPV-negative HNCs. These data aim to guide future deescalation endeavors and functional experiments.

Funding: This study is supported by the American Cancer Society (RSG TBG-123653), funding support for RAH (T32DC00018, Research Training in Otolaryngology, University of Washington), funds to EM from Seattle Translational Tumor Research (Fred Hutchinson Cancer Research Center), and center funds from the Fred Hutchinson Cancer Research Center to EM. UD is supported by the Department of Veterans Affairs, Biomedical Laboratory Research and Development (BLR&D), grant IO1-oo23456, and funds from the Pittsburgh Foundation and PNC Foundation.