We used next-generation sequencing of circulating cell-free DNA (cfDNA) to monitor the response of a KITp.L576P-mutant metastatic vaginal mucosal melanoma to sequential targeted, immuno- and chemotherapy.
The incidence of KIT mutation was significantly higher in older individuals (OR=1.296, 95% CI: 1.025-1.641; P=0.031), and showed a positive association with mucosal melanoma (OR=1.363, 95% CI: 1.094-1.697; P=0.006), acral melanoma (OR=1.374, 95% CI: 1.123-1.682; P=0.02), and CSD (OR=1.880, 95% CI: 1.127-3.136; P=0.016), but a negative relationship with melanomas arising in non-CSD skin (OR=0.562, 95% CI: 0.392-0.805; P=0.002).
The acral/mucosal melanoma subtype is characterized by aberrant and constitutive activation of the proto-oncogene receptor tyrosine kinase C-KIT, which drives tumorigenesis.