Skin cells become cancerous by going through mitosis uncontrollably. When mitosis is working properly cells are only replicated when they need to replace a dying or damaged cells, but sometimes this process does not work and starts to create and divide cells when they are not needed. After many times of division the DNA within the cell starts to have mutations and this will then not be seen or detected by the body. The cells keep mutating and dividing until it develops into a tumor. When the tumor breaks through the basement membrane it gains blood vessels in a process called Angiogenesis. Without this process the tumor would not be able to get nutrients from the blood. Once the tumor does this it starts to spread to other parts of the body
