Skin cancer in dogs: Frequently asked questions answered

Hearing from your vet that your dog has skin cancer can be overwhelming. It's natural to feel a flood of questions as you seek to understand what this diagnosis means for your beloved pet.

This article addresses some of the most frequently asked questions about skin cancer in dogs, providing clear and compassionate answers informed by the latest UK veterinary guidance in 2025.

What is skin cancer in dogs?

Skin cancer refers to several types of malignant growths that can develop on a dog’s skin. The most common types are mast cell tumours, malignant melanomas, and squamous cell carcinomas. Each type has distinct characteristics and may vary in cause and behaviour. Your vet will identify which type affects your dog and explain what it means in detail.

How common is skin cancer in dogs?

Skin cancer is actually the most frequently diagnosed form of cancer in dogs overall. This means that, compared to other cancers, skin cancer occurs more often in canine patients. However, not all skin lumps are cancerous—up to 60-80% of skin tumours are benign. This underscores the importance of professional evaluation for any skin abnormalities.

What are the signs of skin cancer in my dog?

Signs can vary greatly depending on the tumour type and your dog’s skin and coat. Typical reminders for regular skin checks include:

• New or changing lumps, bumps, or growths
• Wart-like formations or raised red areas
• Change in skin colour—spots that are pink, brown, black, red, or grey
• Rough or ulcerated patches of skin

If you notice any unusual skin changes, it’s important to have your vet examine your dog promptly. Early detection often leads to better treatment outcomes.

How is skin cancer diagnosed?

Diagnosis involves your vet conducting a thorough physical examination, then collecting tissue samples usually by fine needle aspiration or biopsy. Samples are sent to specialised pathologists to determine if the growth is malignant and to understand its severity. Additional tests, such as blood work and imaging, may be recommended to check for possible spread.

What treatment options are available?

Surgery is the primary and most effective treatment, aiming to completely remove the cancerous tissue. In some cases, adjunct therapies such as chemotherapy or radiotherapy might be advised, especially for aggressive tumours like mast cell tumours or malignant melanomas. For certain melanomas, immunotherapy such as the Oncept® vaccine can be an option. Ongoing monitoring after treatment is crucial to catch any recurrence early.

Can skin cancer be prevented?

While not all skin cancers can be prevented due to genetics and other factors, you can reduce risk by minimising sun exposure, especially for dogs with light-coloured coats or those that sunbathe frequently. Providing shade and using vet-approved sun protection can help prevent sunburn, a leading cause of skin cancer. Regular skin inspections at home and routine veterinary check-ups also aid in early detection.

What is the prognosis for dogs with skin cancer?

Many dogs diagnosed with skin cancer—particularly when caught early—have a good prognosis following appropriate treatment. The outlook depends on the tumour type, its location, size, and whether it has spread. While approximately 30% of mast cell tumours may be biologically aggressive, most respond well to surgery, with or without additional therapies.

Every case is unique, so ongoing communication with your vet is essential to tailor the best care for your dog.

FAQs: What do UK vets recommend?

Q: How can I tell if a lump is cancerous?

Only a vet can confirm whether a lump is malignant through biopsy or fine needle aspiration. Appearance alone is not reliable.

Q: Are certain breeds more at risk?

Yes, breeds like Boxers and Bulldogs have a higher incidence of mast cell tumours. Knowing your dog’s breed-related risks helps with monitoring and prevention.

Q: If my dog has skin cancer, can they still live comfortably?

Yes, with proper treatment and veterinary care, many dogs continue to enjoy a good quality of life.

Responsible ownership note

If you are considering adding a dog to your family, always choose reputable breeders or consider adoption. Responsible acquisition supports healthier pets and reduces unethical breeding practices.

Regular veterinary check-ups and prompt attention to skin changes are key to safeguarding your dog’s health. Early diagnosis and treatment can make a significant difference.

We hope this guide provides clarity and reassurance during a challenging time. Always reach out to your vet for personalised advice tailored to your dog’s needs.