Growing Brown Spot in a Puppy's Iris

It's hard to see something like this in a new puppy. Some pigment spots in young dogs are nevi, small, well-defined, slightly raised spots that are seen mostly in young dogs. The way to tell them apart from a tumor is to watch whether they change. A short recheck, like your specialist suggested, is a common and sensible approach, and it costs far less than surgery.

Most dark tumors inside the eye are benign. When treatment is needed for one confined to the iris, laser treatment through the cornea has a high success rate. In one small study, the laser shrank every presumed iris melanoma treated, with no regrowth for up to four and a half years. It still needs monitoring afterward, which is probably why your specialist couldn't promise it will go away.

Waiting two weeks is reasonable while he's comfortable. Take a clear photo of the eye in the same light every few days so you can compare. A second opinion from another veterinary ophthalmologist is also fine if it would give you peace of mind. Go back sooner if the eye turns red or cloudy, he squints, or the pupil changes shape.

See dark spots in a dog's eye.

This is general information, not a diagnosis. Please follow your own vet's advice.