The most common forms of skin cancer are Basal cell carcinoma (about 80%) Squamous cell carcinoma (about 16%) Melanoma (about 4%) The less common forms of skin cancer are Paget disease of the nipple or extramammary Paget (usually near the anus) Kaposi sarcoma Merkel cell carcinoma Atypical fibroxanthomas Tumors of the adnexa Cutaneous T-cell lymphoma (mycosis fungoides) Bowen disease is a superficial squamous cell carcinoma.