Skin Cancer in Dogs – How to Recognise It and What to Do
New lumps on your dog’s skin may look harmless – but as many as 20% of them are tumours. Early detection and treatment significantly increase the chances of a cure. See how to recognise different types of skin tumours, when to act, and what treatment options are available.
In this article you’ll find:
- The most common skin tumours in dogs (mast cell tumour, melanoma, histiocytoma)
- Symptoms that should raise concern
- Diagnostics step by step – from observation to biopsy
- Treatment methods – from surgery to radiotherapy
- How to prevent it – prevention and monitoring
🔍 Types of skin tumours in dogs
Mast cell tumour
This is the most common skin tumour in dogs. It initially appears as a round, raised lump. The histamine released causes swelling, redness and itching. It often occurs in dogs aged 8–10, especially boxers, pugs and Boston terriers. Swift surgical intervention gives excellent prognosis, although the tumours can recur.
Histiocytoma (Langerhans cell tumour)
Appears in younger dogs, often on the ears or muzzle. Usually red and small – up to 2.5 cm. In most cases it resolves on its own, but it can be surgically removed to confirm the diagnosis.
Melanoma
Can occur on the skin, in the mouth or between the toes. It is not always pigmented. Malignant melanomas are aggressive and require surgery, often toe amputation. Schnauzers, cocker spaniels and retrievers are at higher risk.
🔎 When to see a vet?
- A lump appears suddenly or is growing
- It changes colour, bleeds or is clearly raised
- The dog tries to scratch it and there are signs of inflammation
- It affects breeds prone to skin tumours
Watch any new lump for a month – take a photo and note the date.
🩺 Diagnostics step by step
- The vet examines the tumour and may perform a fine needle aspiration (FNA).
- If the result is inconclusive — a biopsy or full removal.
- Sometimes helpful: X-rays, ultrasound, blood tests to determine the stage of the disease
💉 What treatment methods are available?
- Surgery – the primary method of removing the tumour with a tissue “safety margin”.
- Radiotherapy – indicated for locations that are difficult to operate on, e.g. the head area.
- Chemotherapy – used if the tumour was malignant or has metastasised.
Early diagnosis gives a high chance of a full recovery.
🛡️ How to prevent it?
- Once a month, do a thorough “skin check” of your dog – especially for breeds prone to it.
- Protect your dog from the sun – UV burns can lead to squamous cell carcinoma; use appropriate sunscreen and clothing for light-skinned dogs.
- Regular check-ups help detect tumours at an early stage.
✅ Summary
- Most skin lumps in dogs are not dangerous, but they should never be ignored.
- Mast cell tumours and melanoma are the most common tumours – early intervention gives a chance for good health.
- Diagnostics are quick and effective.
- Prevention and a monthly skin check are key to your dog’s health.
