Stratum basal layer of the epidermis are 10–25% of the cells melanocytes, a cell type that is prone to cancer in the form of melanoma.
Due to its dual roles as a tumour initiator and a tumour promoter, UV radiation is categorised as a "complete carcinogen" since it is both a mutagen and a non-specific harmful agent. UV exposure is the most significant environmental risk factor that can be altered for skin cancer and many other skin conditions that are impacted by the environment.
The layer of basal cells at the deepest section of the epidermis contains melanocytes.
Cancer that starts in melanocytes is called melanoma. This cancer is also known as cutaneous melanoma and malignant melanoma.
Melanoma tumours are often brown or black because the majority of melanoma cells still produce melanin.