Causes of Canine Skin Cancer

Canine skin cancer is caused by an abnormal growth of cells. Although cancer may occur in pets of varying ages, older dogs are most susceptible to cancer. Tumors can develop in any part of the dog's body and if they're malignant, they have to be removed to prevent metastasis.

How Does Skin Cancer Develop?

Skin cancer develops when there is a sudden and uncontrolled growth of cells that don't die, but rather turn into abnormal cells. Since these cells are capable of multiplication, they replace normal cells and cause damage to the body. Cancer cells destroy DNA that's present in every cell in the pet's body. Once the DNA is damaged due to cancer, it can't be medically restored to normal. Unlike most other pets, skin cancer is the most common form of cancer in dogs. Certain dogs are also genetically predisposed to developing skin cancer.

Breeds Susceptible to Skin Cancer:

  • Bassett hounds
  • Norweigian elkhounds
  • Boxers
  • Scottish terriers
  • Bull mastiffs


Tumors that develop due to abnormal cell growth can be classified as benign skin tumors and malignant skin tumors. Benign skin tumors don't develop as much as malignant tumors, and cause no pain. The classifications of benign skin tumors include lipomas, pappillomas, melanomas and other tumors. Malignant skin tumors may be classified as squamous cell carcinoma, mast cell tumors, hemangiosarcoma and fibrosarcoma.

Causes of Canine Skin Cancer

Although the cause of abnormal cell growth hasn't been established, certain forms of cancer have been linked to environmental factors and heredity. Squamous cell carcinoma manifests itself in lumps and sores that occur in the epidermis. According to research, sun exposure or damaging sun rays are responsible for this type of cancer. Most pets have sufficient hair coats to protect them from the sun. However, certain parts of the body, such as the nose and foot pads, are exposed to the sun's rays. DIn addition, dogs with scanty hair or light colors are more susceptible to skin cancer caused by the sun. Dogs with a genetic predisposition may also develop malignant melanomas and mast cell tumors. Increasing research indicates a link between bodily hormones such as estrogen or progesterone and skin cancer development.

Skin Cancer in Dog Breeds

The type of skin cancer that develops in dogs also differs by the breed. Light skin and short haired dogs such as dalmatians, beagles and collies are more susceptible to squamous cell carcinomas. Pets like Labrador retrievers and schnauzers are likelier to develop mast cell tumors.

Treatment Options

After appropriate diagnostic tests such as fine needle aspiration, biopsy and ultrasounds, the pathologist will be able to determine the grade or severity of cancer development in pets. Most pets require surgical removal of the tumor. Chemotherapy is also used alongside surgery to slow cancer progression. The treatment is based on individual pet conditions and can be altered according to the pet's response to treatment. Radiation therapy may also be used to shrink mast cell tumors if they're located in certain places where surgery maybe inappropriate.

Pets suffering from skin cancer require prompt medical treatment to prevent rapid cancer development. The prognosis is best when pets are suffering from low grade cancers that can be managed with surgery and chemotherapy.