My Mother Who Is 100 Years Old Has A Cancer

My mother who is 100 years old has a cancer on her back high up on her shoulder that began as a pin cushion looking cancer that bleeds. It has grown like a mushroom at a rapid rate and is red and bleeds a lot. The hospice nurses keep it bandaged with some sort of medication applied directly to try to cauterize it. When I was there visiting her the nurse changed the bandage and there was black secretions coming from it along with the bleeding. What is this type of skin cancer?