My dog has a brown spot in his eye. Should I worry about cancer?

My last visit to my dog's ophthalmologist was quite a bit less than surgery would be to remove his eye, so before making any rash decisions, I would find out the cost of seeing the ophthalmologist. Unfortunately, it is very difficult to determine if a mass in the anterior chamber is an iris cyst (which is benign) or a melanoma, but one trick is that an iris cyst may move in the eye. So if Tia is on her back, does the mass move? If so, be sure to give your doctor that information. I wish I had a simple answer for you, but I hope that was helpful. Thanks for using Petco Pet Education Center, formerly Petcoach.

Hi, this looks like an uveal cyst which is a benign condition that can be easily distinguished from a melanoma by the perfectly spherical shape and by being translucent when trans illuminated during ophthalmic examination. Most uveal cysts generally occur without any precedent or concurrent ocular disease and originate from the pigmented epithelium of the iris or ciliary body. Theories exist suggesting the cysts are present at birth, but do not start to grow and slowly detach to become free-floating until later in life. As the cysts grow, they may become “wedged” in the visual axis and sometimes cysts collapse spontaneously, leaving pigmented deposits on the central to ventral corneal endothelium. There is no absolute answer to whether uveal cysts require treatment. In many dogs, single or multiple cysts may be present, floating in the anterior chamber, without any obvious effect on the dog’s visual behaviour. In your case, I would continue to monitor Oscar but given the fact the cyst is quite small, it’s most likely not causing him any problems with his vision even if it should move to the from of the eye and therefore can be left for the time being.

While this could be pigmentary keratitis I am concerned that it looks like the pigment may be inside the eye which would mean that an iris cyst or mass would be more likely. I’d recommend having your vet take a look in person. If it is pigmentary keratitis then your vet would look for things that could cause inflammation or irritation of the cornea like dry eye, abnormal eyelashes or an inability to fully close the eye.

Black spots on a dogs eye indicates either an eye freckle or eye tumor. The next step is to get your vet to do a complete eye exam, which then may lead to a second opinion through a veterinary ophthalmologist to confirm. I do hope that this is just an eye freckle, but it is impossible to say for sure with just a photo. I wish you all the best moving forward with Beck. Best wishes and take care. : )

Thank you for contacting PetCoach with your question about Ellie. The pigmentation can grow over time. I will put a link below to an article as to what this could be. If this is pigmentary keratitis, the underlying cause needs to be diagnosed so it can be treated correctly. Even if this was a melanoma, yes they are usually benign in dogs. In fact, 80% of them are benign. If it was melanoma, it could be destroyed with a laser since it's small. Have her see a veterinary ophthalmologist before getting too worried about it. Best of luck. https://www.northwestanimaleye.com/pigmentary-keratitis.pml

It could be iris melanoma but there is no way to know just by looking at a photo. You should have a veterinary ophthalmologist check the eye if you are really worried. At Cali's age I highly doubt it is melanoma but it is possible.

I recommend to have Cassie examined by the veterinarian. It's possible this is a benign iris cyst BUT it could also be melanoma or some other type of cancer. Once the doctor can determine where the black blob is found within the eye, this will give a better idea of what it could be. Cassie may also need a referral to a specialist. I hope this helps.