Malignant Melanoma within a Cellular Blue Nevi Presenting as a Vascular Malformation and the Connection to Sporadic KRAS Mutations.

We present a case of malignant melanoma (MM) developing within a vascular malformation showing features of cellular blue nevi. A 47-year-old male presented with acute symptoms of a temporal and zygomatic mass, which were both previously asymptomatic upon development 30 years ago. These masses were diagnosed as vascular malformations upon imaging and were treated with sclerotherapy. Embolization and surgical excision were performed 3 years later due to symptomatic growth. Final pathology reports showed MM with congenital blue nevi. We hypothesize a possible linkage to a sporadic mutation, linking both presentations of vascular malformation, MM, and cellular blue nevi. A literature search for similar cases is also reported.