My 90-year Old Father Has Type 2 Diabetes And A

My 90-year old father has Type 2 diabetes and a pacemaker, but otherwise is in good shape. He has a growth on the top of his head (for over 6 months) that is half an inch high and at least as big around as a nickel. It will not heal and in fact has grown. It's also nearly black in color and it flakes off. He said the doctor told him 6-8 months ago that it was not cancer. His next appt with a dermatologist is not until January. Shouldn't he go see someone sooner? Couldn't this be cancer? His care is through the VA, but I told him I would pay for him to go see someone even if it's redi-care.