What should you know about dog iris melanoma?

The iris is the coloured part of the eye. A dark spot, uneven pigment, raised area, enlarged pupil, redness, cloudiness, or a change in eye shape can have several explanations. Melanoma is a cancer arising from pigment-producing cells, but appearance alone cannot confirm it. A veterinarian may examine the eye with magnification, assess pressure and vision, and decide whether referral to a veterinary ophthalmologist or oncologist is needed. General information about [Melanoma](/conditions/melanoma/) does not replace an eye examination.

Book a prompt veterinary appointment and photograph the eye in consistent lighting if this can be done without delaying care. Note when the change began, whether it is enlarging, and whether the dog is rubbing the eye or avoiding light. Do not use leftover eye drops. Depending on findings, discussions may include observation, [Tumour Removal Surgery](/treatments/surgical-oncology/tumour-removal-surgery/), [Surgical Excision](/treatments/surgical-dermatology/excisional-surgery/), or other eye-sparing or eye-removing procedures. The choice depends on location, depth, vision, and spread.

Seek same-day veterinary care for sudden vision loss, severe pain, marked redness, a bulging eye, bleeding, cloudiness, or repeated rubbing. Urgent review is also appropriate when the pupil changes or the eye rapidly enlarges. If melanoma is confirmed, staging may involve lymph-node assessment such as [Sentinel Lymph Node Biopsy](/treatments/diagnostics-and-staging/sentinel-lymph-node-biopsy/) and imaging; spread to distant sites requires specialist planning.

What changes do you see in the iris, pupil, pressure, and vision? Is referral to an eye specialist needed? Should the lesion be sampled or removed? What are the goals and risks of surgery, and how will follow-up detect recurrence or spread?