Just like cancer in humans, cancer in dogs results from the abnormal and uncontrolled growth of cells in the body. Cancerous cells develop when the DNA of a dog has been somehow damaged. While the body can often repair damaged DNA on its own, in cancer cells, the damage is not repaired. As with humans, dogs can get many different types of cancers. In white Labradors, as in other light-colored dogs, skin cancer is a major concern.
A dog's chances of getting cancer increase with age, and cancer is the leading cause of death in dogs over the age of 10. In white Labradors, skin cancer is most common. Like humans, dogs with very light-colored coats and skin are more susceptible to skin damage from the sun's rays. Prolonged, unprotected exposure to harmful ultraviolet rays can result in skin cancer. Labradors are active dogs that love to be outdoors. This means that they are likely to receive a lot of sun exposure over the course of their lives.
One key to preventing skin cancer in your white Lab is to make sure he has protection against damage from the sun. When taking your white Lab outside, make sure to use a sunscreen on him. Because dogs can lick themselves and sunscreens for humans contain chemicals that may be harmful to your dog if ingested, it's important to use a sunscreen designed specifically for dogs. Remember that Labradors are water dogs and as such will jump---literally---at the chance to swim. If you think your dog may get wet while outside, use a waterproof sunscreen that will stay on.
Obviously, your white lab's color alone makes him exponentially more likely to get skin cancer than dogs of other colors. However, your dog is much more likely to develop skin cancer if he is middle-aged or older as well, so it's important to remain vigilant if your white Lab is getting up there in years.
Skin cancer often presents as a lump in or underneath the skin or as a sore that refuses to heal. Additionally, your white Labrador may experience discomfort or itching at a specific spot on his body. This may be early-stage skin cancer. Redness of the skin, and a flaky appearance, may also signal that your white Lab has skin cancer.
Diagnosis and Treatment
If your veterinarian suspects cancer, he may order a series of tests, including blood tests and even biopsies. Treatment may include a combination of chemotherapy, radiation, and cryosurgery. However, because most Labradors are in their senior years when they develop cancer, your veterinarian may ask you to consider sparing your dog the pain and discomfort of treatment and focus instead of making his last months or years as enjoyable as possible.