Malignant Melanoma in Dogs

Melanoma in dogs occurs in the melanocytes, which are the cells that regulate pigmentation levels in your dog's body. Some breeds are more susceptible to this type of cancer than others. Here's what you should know about malignant melanoma in dogs. 

Risk Factors for Canine Malignant Melanoma 

Dogs older than nine years of age are most likely to develop malignant melanoma. Male dogs develop this type of cancer more often than do females, and black dogs also seem more likely to develop it. 

Certain breeds are more vulnerable to malignant melanoma than others. Breeds prone to this type of skin cancer include:

  • Chow Chow
  • Doberman Pinscher
  • Scottish Terrier
  • Golden Retriever
  • Cocker Spaniel
  • Airedale Terrier
  • Boxer
  • Irish Setter

Symptoms of Malignant Melanoma in Dogs

Melanoma tumors usually appear on or inside of the mouth; they're also common on the toes, but can occur anywhere on your dog's skin. Melanoma tumors may be the same color as your dog's skin, or they may be black in hue.

If your dog grows melanoma on the skin of his body, it will most likely appear on the feet, face, scrotum or torso. If your dog develops malignant melanoma inside his mouth, he may develop halitosis, have trouble eating, bleed from the mouth or drool excessively. His face may swell up and you may be able to see the tumor inside of his mouth. If the melanoma spreads to his lungs, he could begin to have breathing problems.

Canine Malignant Melanoma Diagnosis

Your vet will need a complete medical history and a thorough physical exam in order to diagnose malignant melanoma. Chest X-rays can tell your vet if the cancer has already spread to your dog's lungs. Your vet may use a fine needle aspirate to remove cells for biopsy in the lab. Ultrasounds can help your vet determine if the disease has spread to other organs throughout the body.

Treating Malignant Melanoma in Dogs

Surgical removal is a very effective treatment for melanoma tumors that have not yet spread. Your vet may want to remove a large amount of the healthy tissue surrounding your dog's tumor. This can help keep the tumor from coming back. 

If your vet can't remove the entire tumor, or if the cancer has already spread, then your dog will need chemotherapy. Your vet may recommend using radiation therapy in conjunction with chemotherapy. Melanoma is a very aggressive cancer that spreads quickly, so multiple treatments are often used at once. 

The newly developed canine melanoma vaccine may help your dog recover from malignant melanoma. The vaccine stimulates your dog's immune system to act against the melanoma tumor cells. Researchers have not yet fully explored the benefits and risks of this vaccine, but studies suggest that it could be of immense benefit in increasing the life span of dogs diagnosed with canine malignant melanoma

Vets don't know what causes melanoma in dogs, so it's hard to prevent. Monitor your dog's skin for growths and seek veterinary care immediately if you suspect your dog has developed melanoma. Early detection is key to fighting this aggressive cancer.