Abstract:
Objective To discuss and analyze the significance of gene mutation types and gene copy number variations (CNV) by comparing their differences between acral melanoma (AM) and non-acral melanoma (NAM).
Methods This study included the data of 73 patients with cutaneous melanoma admitted to Affiliated Tumor Hospital of Xinjiang Medical University from January 2018 to January 2021. All patients underwent comprehensive genomic testing of 46 cancer-related genes using next-generation sequencing (NGS) technology. They were assigned into AM and NAM groups (AMs and NAMs) according to different tumor sites, and the clinicopathological characteristics, gene mutation types, and gene CNV between the two groups were compared.
Results There was no significant difference in gender, age, tumor thickness, ulcer, lymph node status, and tumor stage between the two groups (P>0.05). The most common mutation types in 73 patients were BRAF (20.5%), KRAS/NRAS (17.8%), and KIT mutations (13.7%). There was a significant difference in the frequency of BRAF mutations in NAMs compared with AMs (P<0.05). There was a significant difference in the BRAF mutation rate between patients≤65 years and patients>65 years (P<0.05). In addition, melanomas without ulcers were more likely to have BRAF mutations than melanomas with ulcers (P<0.05). There was no significant difference in KRAS/NRAS and KIT mutation rates between the two groups (P>0.05). The CNV of cell cycle aberration (CDK4/6, CCND1/2, CDKN2A), receptor tyrosine kinase (EGFR, MET, ERBB2, ERBB3, PDGFRA), and anti-apoptosis genes (BIRC2/3/5) were significantly different between AMs and NAMs (P = 0.019, 0.002, 0.027).
Conclusions The analysis of AM and NAM gene mutation types and CNV provides a better understanding of the carcinogenic patterns and clinicopathological characteristics of cutaneous malignant melanoma.