Table 2.

Comparative pathology and molecular features of vulvar and vaginal malignant melanoma.

Feature	Vulvar malignant melanoma	Vaginal malignant melanoma	Clinical implication
Histologic subtype	Lentiginous/mucosal type; nodular type; superficial spreading (50)	Predominantly nodular; invasive mass; limited in situ phase (50)	Vulvar precursor phase; vaginal de novo invasion
BRAF mutation	Low frequency; test routinely; non-V600 variants (50, 51)	Low frequency; rare V600; noncanonical variants (50, 51)	Limited BRAF-targeted eligibility
KIT mutation	Relatively common; 21.6%-27% (50, 51)	Lower frequency; approximately 8% (50);	Key actionable target in vulvar malignant melanoma
NRAS mutation	Lower frequency; approximately 10.2% (50); variable association	Higher frequency; nodular lesions (50); MAPK activation	Greater MAPK-pathway dependence