Cat with black spot or scab on his nose

[SputniksMom]

Hello, I have a black and white cat who is about 10 years old. He lived the first few years of his life in the alley but since I adopted him in 2001 he's been an indoor cat. About 6 months ago he developed a funny little black spot on his nose. The spot stays around for 3-4 weeks and then it falls off. When it does, the skin underneath is slightly red. Then the spot returns. I'm not sure if it's a scab or what, but it worries me a bit. I've attached a picture. Should I be worried?

[SputniksMom]

Here's a follow up. I took him to the vet and the vet said it was nothing to worry about. If I understood correctly, he said there was some special kind of skin right where the skin of the nose meets the fur and that it's prone to bacterial infections... so the little spot was an infection. He said you can sometimes try to treat them with antibiotics, but it's generally not worth it.

So... no nose cancer!! Yippee!!

[SputniksMom]

Here is a bigger version of the picture: http://www.zingerbug.com/images/sputtys_nose.jpg