
Cancer is one of the leading causes of death in dogs and while it may not be entirely preventable, there are several actions pet owners can take to significantly reduce the risk. As with many diseases, early detection and proactive care are essential. The following are important steps that can help prevent cancer in dogs, along with insights into how certain dog breeds are more susceptible to the disease.
Understanding Cancer in Dogs
Cancer develops when cells within the body begin to grow uncontrollably, forming masses or tumors. Tumors in dogs can be categorized as benign (non-cancerous) or malignant (cancerous), with malignant tumors having the potential to spread to other parts of the body. Malignant tumors have the potential to spread to other areas of the body, making them more threatening. Some of the most frequently seen types of cancer in dogs include:
- Lymphoma: Lymphoma is a type of cancer that affects the lymphatic system, which plays a crucial role in the immune system.
- Mast Cell Tumors: These tumors can occur in the skin, but can also spread to internal organs.
- Osteosarcoma: Osteosarcoma is a form of bone cancer that primarily affects large breed dogs, often leading to painful and aggressive tumors in the bones.
- Hemangiosarcoma: A cancer of the blood vessels that often affects the spleen and heart.
- Mammary Tumors: Tumors that develop in the mammary glands, common in unspayed females.
While age and genetics play a significant role, certain lifestyle changes and interventions can help decrease the likelihood of developing cancer.
Actions You Can Take to Reduce the Risk of Cancer in Dogs
1. Regular Vet Check-ups

Regular vet visits are one of the most effective ways to catch early signs of cancer. Identifying cancer early greatly improves the likelihood of successful treatment outcomes. During these visits, the vet may conduct routine blood tests, ultrasounds, X-rays, or biopsies if they find any unusual lumps, bumps, or changes in your dog’s health.
Pro Tip: Pay close attention to changes in your dog’s behavior or physical appearance. If you notice any lumps, difficulty breathing, excessive drinking, sudden weight loss, or lethargy, it's important to get them checked out immediately.
2. Healthy Diet
A high-quality, nutrient-rich diet can help boost your dog’s immune system and lower the risk of cancer. Commercial pet foods that contain fillers, artificial preservatives and unhealthy fats may contribute to the development of health issues. Instead, choose pet food that uses high-quality ingredients, such as animal proteins, vegetables and healthy fats.
There are also specific ingredients you can include to further benefit your dog’s health:
- Antioxidants: These help neutralize free radicals in the body, which can cause cell damage. Foods such as blueberries, sweet potatoes and carrots are packed with antioxidants, which help protect the body’s cells from damage caused by free radicals.
- Omega-3 Fatty Acids: Found in fish like salmon and sardines, omega-3s help reduce inflammation and support overall immune health.
- Curbing Processed Foods: Avoid heavily processed treats that contain preservatives, artificial colorants, or byproducts. Opt for healthy, natural snacks like carrots, apples, or specially formulated pet treats.
3. Exercise and Healthy Weight Maintenance

Obesity is linked to several cancers, including breast cancer and some types of lymphomas. Maintaining a healthy weight for your dog is one of the most powerful methods to lower the risk of cancer. Regular exercise doesn’t just help with weight management—it also helps your dog maintain strong muscles, a healthy heart and a properly functioning digestive system.
Exercise Tips:
- Aim for at least 30 minutes to an hour of physical activity per day, depending on your dog’s breed and energy level.
- Play interactive games like fetch, tug-of-war, or hide-and-seek to make exercise fun.
- If your dog is a senior or has mobility issues, consider low-impact activities like swimming or gentle walks.
4. Spaying and Neutering
Spaying female dogs and neutering male dogs can help prevent certain cancers. Spaying female dogs before their first heat cycle greatly reduces the risk of developing mammary tumors. Neutering male dogs before puberty eliminates the risk of testicular cancer and reduces the risk of prostate issues.
Additionally, spaying and neutering can help prevent other health issues, such as pyometra (a severe uterine infection) and behavioral issues like aggression or roaming.
5. Minimize Exposure to Environmental Toxins
Dogs, like humans, can be affected by environmental pollutants. These may include pesticides, herbicides, industrial chemicals and tobacco smoke. Some studies suggest that exposure to these toxins can increase the risk of developing cancers such as lymphoma and hemangiosarcoma.
How to Reduce Exposure:
- Refrain from using chemical pesticides or fertilizers in your yard to reduce your dog's exposure to harmful toxins.
- Choose organic or natural options for pest control if you need to treat your yard.
- Keep your dog away from secondhand smoke—never allow them to be around smoking areas.
- Be cautious with household cleaners and opt for pet-safe or natural cleaning products.
6. Limit Sun Exposure
Dogs with thin or light-colored coats are especially vulnerable to skin cancers, such as squamous cell carcinoma and melanoma, caused by excessive UV radiation. To protect your dog:
- Limit sun exposure during peak hours (10 a.m. to 4 p.m.).
- Apply pet-safe sunscreens to areas such as the nose, ears and belly, which are particularly vulnerable to sunburn and skin cancer in dogs.
- Provide shaded areas for your dog to rest in during hot days.
- If your dog has a light-colored or short coat, consider protective clothing or a sun-protective doggie shirt.
7. Monitor for Lumps and Bumps

Many cancers in dogs, such as mast cell tumors, begin as small lumps or bumps on the skin. Consistently inspect your dog’s body for any changes, such as lumps, bumps, or skin abnormalities. If you find a lump, don’t panic. While many lumps are benign, it’s essential to have your veterinarian check them to rule out cancer.
Self-examination Tips:
- Gently palpate your dog’s body when they’re relaxed and comfortable.
- Check for lumps, bumps, changes in skin texture, or any areas of irritation.
- If you notice a change in size, texture, or mobility of a lump, have it evaluated by a vet.
Dog Breeds Prone to Cancer
Some dog breeds have a genetic predisposition to developing certain types of cancer. It’s important for owners of these breeds to be aware of the risks and take extra precautions.
- Golden Retrievers: Golden Retrievers are highly susceptible to cancer, especially hemangiosarcoma (a cancer of the blood vessels), lymphoma and mast cell tumors. Approximately 60% of Golden Retrievers will be diagnosed with cancer by the time they reach age 10. Regular screenings and early detection are critical for this breed.
- Boxers: Boxers are particularly prone to developing lymphoma, mast cell tumors and brain tumors. They tend to develop cancer at younger ages compared to other breeds. A Boxer with any sudden or unusual symptoms should be seen by a vet right away.
- Bernese Mountain Dogs: Bernese Mountain Dogs are predisposed to osteosarcoma, a painful and aggressive form of bone cancer, as well as hemangiosarcoma. Unfortunately, these dogs have a relatively short lifespan and cancer is a leading cause of death for them.
- Cocker Spaniels: Cocker Spaniels are at an increased risk of developing mammary tumors, lymphoma and other skin cancers. Spaying female Cocker Spaniels at an early age can significantly reduce the risk of mammary cancer.
- Doberman Pinschers: Dobermans are vulnerable to various types of cancers, including lymphoma and hemangiosarcoma. Regular screenings and blood tests are recommended for this breed, especially as they age.
- Rottweilers: Rottweilers have a higher incidence of developing osteosarcoma and hemangiosarcoma. Regular vet visits and a healthy lifestyle can help catch any early signs of cancer.
- Scottish Terriers: Scottish Terriers have a genetic predisposition to developing bladder cancer, particularly transitional cell carcinoma. Their predisposition to cancer underscores the importance of regular health check-ups and early screening for this breed.
Conclusion
While cancer in dogs may not always be preventable, taking proactive steps can certainly lower the risk. Regular veterinary visits, a healthy diet, exercise, spaying or neutering and minimizing exposure to toxins are all essential strategies for promoting your dog’s long-term health. Being aware of the genetic risks associated with certain breeds will also help you make informed decisions about care and monitoring. Above all, early detection remains key to successfully treating cancer if it does occur, so always keep an eye on your dog’s health and be sure to consult your vet with any concerns.
By taking these steps, you can significantly improve the odds of your dog leading a happy, healthy life free from cancer.