Investigation of tumor mutation burden using the comprehensive genomic profiling data of vulvar and vaginal malignant tumors: an observational study using C-CAT database

Abstract

Background: This study aimed to reveal the gene alteration and tumor mutation burden (TMB) statuses of vulvar and vaginal malignant tumors in Japan.

Methods: We investigated the cancer genomic profiling (CGP) data of 79 patients with vulvar and vaginal cancers. These data were obtained from the Center for Cancer Genomics and Advanced Therapeutics (C-CAT).

Results: None of the patients had high microsatellite instability. Although 21.9% of the patients with vulvar and vaginal squamous cell carcinoma (SCC) had high TMB, those with other histological types did not. The top single-nucleotide variants (SNVs) in SCC were TERT, TP53, CDKN2A, KMT2D, and NOTCH1. The frequencies of ATRX and PBRM1 were significantly higher in TMB-high SCC than in non-TMB-high SCC.

Conclusion: SCC of the vulva and vagina is expected to have high TMB, and gene alteration status differed between TMB-high and non-TMB-high groups.

Keywords: Cancer genomic profiling; Tumor mutation burden; Vaginal cancer; Vulvar cancer.