Signs & Symptoms of Dying of Cancer in Dogs

Cancer is the leading disease-related cause of death in dogs. According to an article published by the North Carolina State University College of Veterinary Medicine, half of all dogs over 10 years of age will develop some form of cancer, and 25 percent of dogs will die from it. Understanding the signs and symptoms of cancer will not only help you begin treatment early but will help you recognize the stages of cancer. This understanding can aid you in making important decisions for your pet.

Miniature schnauzer on couch
A listless Miniature Schnauzer resting on the sofa.
credit: waldru/iStock/Getty Images

Initial Signs of Cancer

Unless your dog is on a diet, any sudden weight loss is a warning sign that something's wrong, as is loss of appetite. Vomiting, diarrhea, lethargy, reclusive behavior, hair loss, increased urination and increased or decreased thirst can appear during the early stages of cancer. Check your dog for other warning signs such as enlarged lymph nodes, unusual lumps and bumps on the body, coughing or shortness of breath, pale gums and persistent open wounds. To examine the lymph nodes, press gently with your fingertips beneath your dog's jaw near his neck, along the front of the chest, under his front armpits and along the back of the hind leg, just above the hock joint. Check both sides of his body. If you don't feel anything, consider that a good sign.

Late-Stage Symptoms

As terminal cancer progresses, the symptoms of cancer's early stages will persist. Additional symptoms may include severe weight loss, difficulty eating or drinking, difficulty rising, paralysis, seizures, labored breathing and bruising or ulceration of the skin. He may lose his lust for life, refusing attention, playtime or his favorite toys. He may persistently lick or become protective of the areas of his body where tumors exist, sometimes even snapping at those who try to touch him. Symptoms will vary with each dog and depending upon the type of cancer he is fighting.

In Critical Condition

Immediately seek veterinary attention if your dog has extreme difficulty breathing, suffers from prolonged seizures, experiences uncontrollable vomiting or diarrhea, presents ongoing external or internal bleeding, cries out from pain or suddenly collapses. All of these symptoms are life threatening and require medical attention. Your veterinarian can help you decide on the best course for treatment, pain management or euthanasia.

Making Difficult Choices

As your dog progresses through the stages of cancer, you will need to make many choices regarding his care and treatment. Your veterinarian will help you monitor your dog's condition throughout his treatment and will make recommendations concerning his care. Many neighborhoods now have animal hospice care available, offering assistance with ongoing care, emotional support and help with end-of-life decisions. Take into account your pet's overall quality of life, pain level, appetite and overall happiness when making these important decisions.