Neoplastic skin disorders include benign, premalignant, and malignant tumors. Basal cell carcinoma (BCC) is the most common skin cancer, arising from basal cells in the epidermis. Histologically, BCC shows nests of basaloid cells with peripheral palisading. Squamous cell carcinoma (SCC) originates from keratinocytes and is characterized by atypical keratinocytes extending through the epidermis. Melanoma is a malignancy of melanocytes, showing significant cytological atypia and pagetoid spread of cells.
