Frequency of cancer and abnormal growth in genital region

Hi, a question. I have a 6 yr old grey female chinchilla with an abnormal growth in her genital region. It's been looked at by a vet and it could be a skin tag, tumor, or cancerous growth. Honestly, I think I noticed something a while back and thought, "I don't remember chinchilla genitals looking like that" but thought nothing of it as it was small and seemed to fit in.
As she's irritating it (appears to have gnawed at it), it'll need to be removed if the chance of prognosis is decent.

So. What is the rate of cancer in chinchillas?
Non-cancerous tumors?
Skin tags?

Feel free to share any relevant/related experience!