The clinical utility of comprehensive genomic profiling for recurrent / metastatic head and neck cancer

Abstract

Background: Next-generation sequencing （NGS） of tumor samples in a clinical setting provides information regarding cancer-related genetic aberrations, and is therefore expected to be useful in precision medicine. However, the clinical utility of clinical sequencing remains unknown in solid cancers, including recurrent or metastatic head and neck cancer （R/M HNC） in Japan. Here, we conducted a hospital-based study to investigate the clinical utility of tumor-profiling gene panel testing in R/M HNC.
Methods: We examined 18 panel tests from 14 cases of R/M HNC; 15 underwent tumor tissue-based panel testing （FoundationOne CDx® and/or FoundationOne HEME®） and three underwent liquid biopsy （Guardant360®）, with three cases undergoing both investigations.
Results: There were nine men and five women of median age 58 years （38-73 years）. There were ten cases of squamous cell carcinoma （SCC） and four of non-SCC. The most common genetic alteration was inactivation of TP53 followed by TERT promoter and CDKN2A alterations. There was no suspected hereditary neoplastic syndrome. Gene profiling data was obtained for 11 cases （78.6％） that harbored at least one actionable gene aberration. Two cases （14.3％） had undergone molecular targeted therapy. The median value of the tumor mutational burden （TMB） was 6.0 Muts/Mb （0-34） and the disease control rate of the three cases with high TMB （≥10 Muts/Mb） was 66.7％ （partial response: 2, progressive disease: 1） following treatment with an immune-checkpoint inhibitor such as nivolumab or pembrolizumab.
Conclusions: These results indicate the clinical utility of tumor-profiling multiplex gene panel testing in R/M HNC in Japan.