Scab on 19 year old cats nose

Question
Our cat bunny is female, 19 years old spayed when she was 4 or 5. She's a BIG cat, slightly overweight, her general activity level is very low, she perfers to sleep and watch things to playing or hunting anymore, she's a 100% indoor cat has been for 7-8 years, but before that she was an indoor-outdoor cat she actually won't go outside and scratches at the door if we put her out even on the nicest days.

My concern is this - Bunny has had what started as a very small scab on her nose for close to two possibly three years now. Every so often the scab will fall off leaving a bright pink area and then it just re-scabbs over, it's slowly been growing in area but it's still less than 1 cm by a 1/2 cm right over one nostril and the top front part of her nose. As far as I'm aware she's not doing anything that's causing the injury.

We took her to the vet for that maybe four months ago but the vet was reluctant to do anything or make any recommendations because she is 19, even tho she's otherwise very healthy.

Is there anything we could do? Is there anything we should be doing?

Answer
Sometimes the treatment of some of these thing is worse than the disease itself.  If it is not bothering the cat, then we shouldn't put him through the pain of skin biopsies and the misery of side effects of some of the powerful drugs to treat tumors or deep infections.