Melanoma is the deadliest common skin cancer
Melanoma grows from melanin-making melanocytes, usually in skin but sometimes in mouth, gut, or eye. Roughly 3.1 million people had the active disease in 2015, and 59,800 died of it. Ultraviolet light is the main driver in people with little melanin.
Melanoma grows from melanocytes, the pigment cells between the epidermis and dermis. It usually appears on skin—most often the legs in women and the back in men—but can arise in the mouth, gut, or eye, and in the lung in about 0.01% of primary lung tumours. Doctors discourage the phrase malignant melanoma as redundant, since no benign version exists. About 30% begin in an existing mole; warning signs include rapid growth, ragged edges, colour change, itching, or broken skin, while nodular melanoma may show up as a brand-new lump.
Ultraviolet light is the main cause in people with little melanin, whether from sunlight or tanning beds. The International Agency for Research on Cancer rates tanning beds carcinogenic, and starting them before age thirty raises melanoma risk by 75%. Childhood exposure matters more than adult exposure, repeated severe sunburns add up, and more than 50 moles signals higher risk. Between 5% and 12% of cases are thought to be hereditary; a first-degree relative raises risk about 1.74-fold, and red-hair variants of the MC1R gene also add risk.
Early tumours spread sideways in a radial phase under 1 mm thick and can usually be cut out completely. Once cells turn downward into the dermis, the vertical phase begins and spread through blood or lymph becomes possible, often to the brain. About 40% carry BRAF mutations, and those with V600E or V600K respond better to dabrafenib plus trametinib. US five-year survival is 100% for localized disease, 76% with lymph-node spread, and 35% with distant spread.
In 2015 about 3.1 million people had active melanoma and 59,800 died. Australia and New Zealand have the world’s highest rates, and US men are affected about 1.6 times as often as women. Cases are projected to rise from 331,722 in 2022 to 510,000 by 2040, although newer treatments are lowering mortality.
Source: Melanoma
