close up skin problem `melanoma` the black spot on human back skin.

back biopsy black cancer cancerous carcinoma care cell cells chemotherapy close cosmetology damage dangerous death dermatologist dermatology develops diagnosis disease epidermal freckle health human illness malignant man medical melanin melanocyte melanocytes melanoma metastasis mole nevus patient pigment pigmentation pigmentproducing problem risk skin spot sunscreen symptoms treatment tumor type