Malignant melanoma arises from the epidermal melanocytes, which are neural crest cells involved in the synthesis of melanin (a brown pigment with photoprotective properties). Development of melanoma is the result of multiple genetic mutations. The progression to melanoma usually involves the serine-threonine kinases of the MAPK/ERK pathway (mitogen-activated protein kinase) following mutation of either the N-RAS or BRAF oncogene. On gross pathology, the majority of melanomas appear as hyperkeratotic, black-brown, asymmetric nodules with irregular borders, but the morphology of the lesion mostly depends on the sub-type of melanoma. On microscopic histopathological analysis, each sub-type of melanoma has unique characteristic features.
Melanoma pathophysiology
Skin cancer pathophysiology
Squamous cell carcinoma of the skin pathophysiology
Dysplastic nevus pathophysiology
Basal cell carcinoma pathophysiology
Lipoma pathophysiology
Extramammary Paget's disease pathophysiology
Uveal melanoma pathophysiology