There are three major types of skin cancer:
(1) Basal cell carcinoma (the most common) – The lump slowly gets bigger and may become crusty, bleed or develop into a painless ulcer.
(2) Squamous cell carcinoma (the second most common), which originate from skin cells – The lump is often tender to touch, bleeds easily and may develop into an ulcer.
(3) Melanoma, which originates from the pigment-producing skin cells (melanocytes) but is less common, though more dangerous, than the first two varieties.