Can dogs get cancer? You might be surprised to learn that cancer is common in dogs — so common, in fact, that roughly 1 in 4 dogs will develop some cancer in their lifetime, with the risk increasing after 10 years of age.³ But some cancers are more common than others.
Read on to learn about the basics of canine cancer, what symptoms to look out for, and how common cancers are treated.
There are many different types of cancer in dogs, just like there are many different types of cancer in humans. Here are the top seven types of dog cancers, dog tumors, and neoplasia in dogs and what they look like.
Melanoma tumors are round masses, usually ¼ inch to 2 inches in diameter, and can be found anywhere on a dog’s body.4 Swollen lymph nodes are a main symptom. Generally, melanoma is treated by removing the tumor.
Early detection is key in treating melanoma tumors in dogs. Pet parents should regularly inspect their dog’s eyes, toes, and other areas of the body to spot unusual masses.
Osteosarcoma is the most common type of bone cancer in dogs.⁵ Large breeds of dogs, like poodles, are very susceptible to bone cancers as they grow out of puppyhood. This kind of cancer can be very aggressive, spreading quickly throughout the body. There are many side effects, but the biggest warning sign is sudden lameness. If this happens, take your dog to the veterinarian immediately for an X-ray or MRI.
Common in senior dogs, lung cancer usually requires surgery to correct because of how aggressive it can be. For example, adenocarcinoma of the lung is a fast-growing cancer that makes up 75% of all primary lung tumors in dogs.⁶ Watch out for ragged breathing and lethargy in your elderly dog. It may be a sign that their lungs are compromised.
Mast cells (or basal tumors) are located in the connective tissues right under the skin. Mast cell tumors are prevalent, making up 20% of all skin tumors in dogs.7 Fortunately, this sort of cancer tends to be benign and easy to treat. If you find a potentially cancerous lump on your dog that is firm to the touch or clustered together, call your vet to schedule an appointment.
Canine lymphoma is a cancer of lymphocytes (blood cells) and lymphoid tissues, similar to non-Hodgkin's lymphoma in people. The four main types of canine lymphoma are:
- Multicentric: The most common form of lymphoma and one that affects the entire body
- Alimentary: Fairly common, alimentary lymphoma affects the gastrointestinal tract
- Mediastinal: A very rare form of lymphoma that affects the chest
- Extranodal: A rare form that affects organs outside the lymphatic system (such as the kidney, lung, or eyes)
Symptoms differ according to each type. Vets can diagnose lymphoma through a fine-needle aspiration. Then, they will discuss the best form of chemotherapy to treat your dog’s cancer.
Mammary tumors affect female dogs, with rare occurrences in males. The American College of Veterinary Surgeons explains that mammary tumors are common in female dogs who were either not spayed until after 2 years of age, or never spayed at all.⁸ Poodles, dachshunds, and spaniels most commonly get this kind of dog tumor. Obesity at a young age can increase the risk of this cancer.⁸ Most mammary tumors are surgically removed and sometimes chemotherapy is recommended after the surgery.
Hemangiosarcoma is an extremely dangerous and fast-moving cancer of the blood vessel walls that can cause cancerous tumors on dogs.⁹ The heart, spleen, and skin are the most affected areas, but hemangiosarcoma can be found anywhere in and on the dog’s body. It’s most common in golden retrievers, Labrador retrievers, and German shepherds.⁹
Since this cancer often doesn’t receive a diagnosis until it’s very advanced, pet owners often make quick decisions regarding whether to do emergency surgery and remove the tumor. Sadly, the surgery can cause hemorrhaging during the diagnostic process. Many folks have to make the difficult choice to euthanize their pet.