Final answer:
Squamous cell carcinoma is the second most common skin cancer and it can metastasize if left untreated, requiring treatments like surgery and radiation. Basal cell carcinoma is the most common and rarely spreads. Melanoma is the least common but most deadly form.
Step-by-step explanation:
The second most common type of skin cancer is squamous cell carcinoma(c). It originates from the keratinocytes of the stratum spinosum layer in the epidermis. Representing about two out of 10 instances of skin cancer, it can be more aggressive than basal cell carcinoma and has the potential to metastasize if not treated appropriately. Common treatments include surgery and radiation therapy.
Basal cell carcinoma is noted as the most common skin cancer, frequently occurring on areas exposed to the sun such as the head, neck, arms, and back. It typically affects the basal cells in the stratum basale layer of the epidermis and rarely spreads or metastasizes. Melanoma, while the rarest, is the most deadly of skin cancers, affecting the melanocytes that produce melanin in the skin.