I'm in shock right now. I've just been to the animal opthamologist to have Chenna's eye looked at -- the one that has mysteriously changed colour. Turns out that it's possibly/probably a pre-cancerous iris melanoma. The fact that it's light brown, and not dark brown or black means that it's OK at the moment. But if it starts changing colour, going darker, then . . .
Apparently feline iris melanomas are just about always fatal. The cancer spreads to the other organs and that's it. The moment, the very moment, that her iris shows the merest hint of dark brown or black, it's time to make a decision.
She might have to have her eye out. And even then it might be too late. They would remove her eye and then do pathology tests to establish whether the growth is cancerous, and whether it's had the chance to spread. If not, great. She'll live out her life as 'old Chenna one-eye'. Evidently cats can adjust to being blind, or having just one eye.
The eye-vet didn't sound too perturbed when she first suggested taking the eye out. I'd only been there 5 minutes too. Perhaps it's standard to take no risks and carry out preventative amputation. Because it sounds as though it's quite probable that the growth will turn cancerous. But not certain. How do you make a call on that?
The vet was sufficiently intrigued to call another specialist in for a second opinion, and they seemed confident that it was safe for the moment. We'll revisit in four months and they'll reassess. Meanwhile, I'll be scrutinising that eye on a daily basis!