Types

• Melanomas make up the commonest form of eye cancer in dogs. When a cancerous tumor spreads from other parts of the body, the eye cancer is known as lymphosarcoma.
  
  

Causes

• The exact cause of eye cancer in dogs is unknown. Blue-eyed dogs have a genetic predisposition for developing ocular melanoma, but most incidences of eye cancer in dogs occur with advancing age.
  
  

Symptoms

• Local symptoms of eye cancer in dogs include changes in iris color, signs of discomfort such as pawing the eye, light sensitivity and tearing, a mass or nodule, change in the shape of the pupil, bleeding in the eye, redness and swelling. Systemic symptoms can include lethargy, decrease in appetite, weight loss, and diminished activity. Increased eye pressure from local tumor formation can cause glaucoma.
  
  

Diagnosis

• A diagnosis of eye cancer in dogs is made through a thorough history and physical by the veterinarian that will cover a comprehensive eye exam, blood work including a complete blood count, thoracic and abdominal X-rays, ultrasound of the eyes and an ocular MRI.
  
  

Treatment

• Treatment for eye cancer in dogs can include chemotherapy, although it's response is usually poor, enucleation (eye removal), and surgical removal of the tumor with either laser or conventional surgery. Pathology findings can determine tumor type and grade of malignancy, and, many times, treatment is based on these findings.
  
  

Considerations

• Eye cancer in dogs is rare. Ocular symptoms in dogs are usually caused by benign conditions such as infection, injury or inward turning of the eyelashes. However, when a dog does exhibit eye symptoms, he should be promptly evaluated by a veterinarian so that timely and appropriate treatment can begin, regardless of the condition.