Cancer is the leading cause of death in pets beyond middle age. Thanks to advances in veterinary medicine, successful treatment for pets with cancer is more common, but early diagnosis is important to improve your pet’s prognosis. Our Heritage Veterinary Clinic team wants to help by providing information about pet cancer to help you identify early warning signs and potentially decrease your pet’s cancer risk. 

Common pet cancers

Cancer can manifest in many ways, and can affect any body system. The most common pet cancers include:

  • Lymphoma — Lymphoma is the most common cancer affecting dogs and cats. This cancer can target lymph nodes throughout the pet’s body, the gastrointestinal tract, lymphoid organs in their chest, or specific organs not associated with the lymphatic system. Some dog breeds, including golden retrievers, boxers, basset hounds, and Saint Bernards, are at higher risk. Feline leukemia virus (FeLV) positive cats are also at increased risk.
  • Mammary gland carcinoma — Mammary gland carcinomas typically appear as a small on the abdomen or chest, and are common in unspayed female pets. 
  • Mast cell tumors — Mast cells are immune cells that play a role in allergies, and can form masses in the skin or other body areas, including the spleen, liver, intestine, and bone marrow. These masses can be relatively benign or extremely aggressive and spread to other body parts. Boxers and bulldogs are at increased risk.
  • Squamous cell carcinoma (SCC) — SCC commonly causes cancerous skin lesions in cats. These tumors usually involve light or unpigmented skin, and are most commonly located on the nose, eyelids, and ears.

Pet cancer signs

Knowing cancer signs can facilitate early diagnosis. The following are the top 10 warning signs of cancer in pets:

  • Swellings — Many cancers, such as lymphoma, mast cell tumors, and mammary gland carcinomas, cause abnormal lumps or bumps. 
  • Non-healing wounds — Non-healing wounds can indicate infection or cancer, and a veterinary professional should evaluate the area. 
  • Weight loss — Unexplained weight loss can indicate an underlying problem, including cancer.
  • Decreased appetite — Your normally ravenous pet who has become uninterested in food may be sick.
  • Bleeding or discharge — Bleeding or discharge, including vomiting and diarrhea, should be investigated by a veterinary professional.
  • Difficulty eating — If your pet has difficulty eating or swallowing, they may have a lesion in their mouth or neck.
  • Offensive odor — Tumors in the mouth, nose, and anus commonly cause foul odors.
  • Exercise intolerance —Your normally active pet who loses their stamina may be ill.
  • Persistent lameness — Lameness is typically associated with arthritis or injury, but cancer may be the culprit.
  • Difficulty performing bodily functions — If your pet has difficulty breathing, urinating, or defecating, they should be seen by a veterinary professional.

Pet cancer diagnosis

Cancer is often suspected based on the pet’s history and physical examination. Other potential diagnostics include:

  • Blood work — Not all cancers can be diagnosed by blood work, but these tests provide insight into your pet’s overall health and can point to affected body systems.
  • Fine needle aspirate — If your pet has new lumps or bumps, our veterinary team will microscopically evaluate a fine needle aspirate from the area. 
  • Urinalysis — A urine sample can provide information about your pet’s overall health, and can identify certain types of urogenital cancer.
  • Imaging — X-rays and ultrasound may be recommended to look for metastasis and evaluate internal tumors.

Pet cancer treatment

Various treatment options are available to use alone, or in combination, to address your  pet’s needs, which will depend on their cancer type, location, and stage. Options include:

  • Surgery — Surgery is the most common technique used to treat cancer in pets.
  • Chemotherapy — Chemotherapy is typically used for cancer that has metastasized, as well as cancer that can’t be treated with surgery or radiation alone.
  • Radiation — Radiation therapy can be used to locally control tumors, such as carcinomas and sarcomas, and to relieve pain or improve function in pets who have advanced cancer.
  • Novel therapies — Novel treatments, such as gene therapy or immunotherapy, may also benefit cancer patients.

Pet cancer prevention

While not all cancer types can be prevented, you can take steps to reduce your pet’s risk, including:

  • Scheduling regular veterinary visits — Schedule regular wellness visits, so our veterinary team can establish a baseline for your pet and detect abnormalities early.
  • Spaying or neutering your pet — Spaying your female pet helps prevent mammary carcinoma, and neutering your male pet helps prevent testicular cancer.
  • Keeping your pet at a healthy weight — Overweight pets are at increased risk for cancer. Calculate your pet’s daily energy requirements and feed them appropriately to help maintain a healthy weight.
  • Avoiding excessive sun exposure — Certain cancers, such as SCC, are linked to sun exposure. Avoid prolonged sunlight exposure, especially around midday when the sunlight is the strongest.
  • Avoiding secondhand smoke — Pets who live with a smoker are at higher cancer risk.
  • Examining your pet — Examine your pet regularly so you can detect changes, such as lumps, odors, and weight loss, as early as possible.
  • Researching your pet’s breed — Check whether your purebred pet is at increased risk for any diseases. 
  • Knowing your pet — Behavioral changes can indicate disease, so monitor your pet for changes in their disposition and sleeping and eating habits. 

Early diagnosis is important to improve your pet’s prognosis if they are affected by cancer. If you notice a concerning lump or behavior change in your pet, contact our Heritage Veterinary Clinic team, so we can make a diagnosis as early as possible and ensure your pet receives the care they need.