Melanoma does not originate from any specific tissue, but from melanocytes. Therefore, melanoma can occur in any tissue where melanocytes are present. The most common sites for melanoma are the skin and mucous membranes. Additionally, because melanocytes are widely present throughout the body, melanoma can also occur in hollow organs such as the gastrointestinal tract, in skeletal muscles, and in the nervous system. Once diagnosed, melanoma needs to be treated promptly. The main treatments include surgery, radiation therapy, chemotherapy, targeted therapy, and immunotherapy.