Final answer:
The primary risk factor for malignant melanoma is exposure to UV light. Light-colored skin, many moles, and a family history of skin cancer also contribute to increased risk. Early detection and treatment are crucial for improving survival rates.
Step-by-step explanation:
The Chief Risk Factor for Malignant Melanoma
The chief risk factor for malignant melanoma is exposure to UV light. Malignant melanoma is a type of cancer that originates from the melanocytes, the pigment-producing cells in the epidermis. Too much UV radiation from the sun or tanning beds can damage the DNA in skin cells, leading to the formation of cancerous lesions. Another significant risk factor includes having light-colored skin, as there is less melanin to protect against UV damage.
Additional risk factors that increase the likelihood of developing melanoma include having a large number of moles, particularly if they are unusual in shape or color, a personal or family history of skin cancer, a weakened immune system, exposure to other forms of radiation, or contact with toxic substances like arsenic. Signs of melanoma include new skin growths, changes in existing moles, freckles, bumps, or birthmarks that may appear as large brown or black patches with uneven borders and a raised surface. Early detection and treatment, often involving surgical excision and immunotherapy, are crucial for a favorable prognosis.