I noticed that Fluffy started to have these spots om the left side of his forehead in April, and recently I saw them grew bigger and they appeared on both sides so I started to worry. Took him to the vet and the vet suggested they are very likely just pigmentation due to sun bath, which he enjoyed a lot lately, or it might be due to a tumor, and a biopsy will be needed to diagnose that. The vet asked me to observe them and see if they grow bigger or if Fluffy has any other symptoms. The spots seem to be a little bit darker since then. Anyone has any similar experiences before, and would you think a biopsy will be needed? Thank you!