Skin problems in dogs can sometimes be dismissed as minor irritations or harmless lumps. However, certain skin changes may signal a more serious condition: skin cancer. In this post, we explore how to recognise skin cancer in dogs, the common types, possible causes, and available treatment options. Our goal is to help pet owners stay informed so that you can act early — because early detection can make a big difference.
Can Dogs Get Skin Cancer?
Yes — contrary to what many might assume, dogs can indeed develop skin cancer. Even though our canine companions are covered in fur, areas with thin or sparse hair, or exposed skin (such as the ears, belly, nose, or paw pads) can still be vulnerable to ultraviolet (UV) rays and other risk factors.
Because of this, regular skin checks and awareness are essential — especially for dogs with light or thin coats, older dogs, or breeds prone to skin disorders.
Recognising the Warning Signs
Skin cancer doesn’t always look the same. The changes can be subtle — or noticeable. Watch out for these warning signs:
- Unusual lumps or bumps on the skin.
- Wart-like growths, or skin-tag–like protrusions that were not there before.
- Discoloration or skin patches that look different (redness, unusual pigmentation, dark or light areas).
- Sores, scabs, or wounds that don’t heal or heal slowly, then reappear.
- Skin lumps that ooze, bleed, or discharge fluid.
- Persistent itching, scratching, or chewing at a particular spot.
- Any sudden changes in an existing mole, wart, lump, or bump — in size, color, shape, or texture.
Because many benign skin conditions (like skin tags, cysts, or simple irritations) can exhibit similar characteristics, it’s important to consult a veterinarian when you notice any suspicious skin change.
Common Types of Skin Cancer in Dogs
Just like in humans, different types of skin cancer affect dogs — and each behaves differently. The most common ones include:
Mast Cell Tumours
These are among the most frequent skin cancers in dogs. Mast cell tumours may appear as raised bumps, nodules, or patches. Sometimes they look inflamed or rubber-like — and might even ulcerate.
While some mast cell tumours grow slowly and remain localised, others can be aggressive. In malignant cases, cancer cells can spread (metastasize) to lymph nodes, the liver, the spleen, or the bone marrow.
Malignant Melanoma
This type originates from pigment-producing cells in the skin. Melanomas often appear as dark (black or brown) lumps — though not always. Some melanomas may even be non-pigmented (pink or light).
In dogs, melanomas commonly occur on the lips, inside the mouth, toes, or nail beds — but they can also appear on other parts of the skin.
While some melanomas remain benign, malignant melanomas can grow fast and spread to internal organs.
Squamous Cell Carcinoma (SCC)
Squamous cell carcinoma often develops in areas exposed to sunlight — such as the nose, ears, belly, legs, or abdomen.
These tumours generally appear as firm, wart-like lumps or rough patches on the skin.
In early or well-defined cases, SCC may be easier to treat. However, left unchecked, SCC can become more aggressive or problematic.
What Causes Skin Cancer in Dogs?
As with human skin cancer, the causes of skin cancer in dogs vary. Some of the known or suspected factors include:
- Sun exposure (UV rays): Skin cells can become damaged from frequent sun exposure, particularly on parts of a dog’s body where the fur is thin or missing, which may raise the chance of developing cancer.
- Thin or light-coloured coats: Dogs with sparse fur or fair skin have less natural protection — making them more vulnerable to UV damage.
- Genetic predisposition: Skin cells can become damaged from frequent sun exposure, particularly on parts of a dog’s body where the fur is thin or missing, which may raise the chance of developing cancer.. Genetic factors can influence susceptibility.
- Environmental factors: Repeated skin trauma, chronic irritation, chemical exposure, or even repeated licking/chewing might contribute to skin damage over time — potentially triggering abnormal cell growth.
It’s worth noting that while we can reduce some risks (like sun exposure), there’s no guaranteed way to prevent all skin cancers — which makes vigilance and regular checks essential.
Diagnosis & Why Early Detection Matters
If you notice any suspicious lumps, skin changes, or lesions — especially ones that persist, grow, or change — you should consult your veterinarian.
Diagnosing skin cancer typically involves:
- A physical examination of the skin, noting size, shape, location, texture, and changes.
- A biopsy or cytology (needle sample or surgical sample) — to examine cells under a microscope and determine if they are benign or malignant.
- Additional tests (blood work, imaging, lymph node or internal organ evaluation) if malignancy or spread is suspected.
Early detection greatly improves treatment prognosis. Many skin cancers — particularly when caught early — are treatable, manageable, and often curable.
Delays in diagnosis may allow the cancer to grow or metastasize, reducing the chances of successful treatment and impacting the dog’s quality of life.
Treatment Options: What You Should Know
Treatment depends on several factors: the cancer type, its location, how advanced it is (stage), and the overall health of your dog. Common approaches include:
- Surgical removal — Often the first and most effective option. If the tumour is small, well-defined, and accessible, surgery may completely remove the cancer.
- Radiation therapy — Used when surgery alone cannot remove all cancerous cells, or when complete excision is difficult due to the tumour’s location.
- Chemotherapy or immunotherapy (or both) — Employed especially when cancer has spread, the risk of recurrence is high, or in malignant cases like certain melanomas or mast cell tumours.
- Targeted therapies — For example, certain medications have been developed to treat specific tumours like mast cell tumours in dogs.
Thanks to advances in veterinary oncology, many dogs with skin cancer go on to live happy, active lives — especially when treatment begins early.
How to Stay Proactive — Prevention & Regular Skin Checks
Because there is no surefire way to prevent all skin cancers, owning a dog responsibly involves regular skin monitoring and proactive habits:
- Regular skin inspections: Get in the habit of gently feeling your dog’s skin all over — head to tail — at least once a week. Pay attention to new bumps, lumps, discoloured patches, scabs, or anything unusual.
- Limit sun exposure: Avoid long, direct sun exposure — especially for dogs with light or thin coats. If you’re out on a sunny day, try to stay in the shade or limit outdoor time during peak sunlight.
- Use pet-safe sun protection: For vulnerable dogs (light coat, short-haired, shaved areas), consider pet-safe sunscreen (as recommended by a vet) and limit time outdoors when UV is strong.
- Prompt vet visits: If you notice any suspicious skin changes — even minor ones — don’t wait. Early veterinary checkups enable early diagnosis, which significantly improves treatment outcomes.
- Maintain overall skin health: Regular grooming, a balanced diet, and avoiding irritants help keep your dog’s skin as healthy as possible — potentially reducing risk.
Final Thoughts
Skin cancer in dogs can be a frightening prospect — but it’s also a reality many pet owners face. The good news: early detection, timely treatment, and vigilant care can make a big difference to your dog's outcome.
At the end of the day, being a responsible and attentive pet owner means paying close attention to what’s “normal” or “not normal” on your dog’s skin. If in doubt — always check with your veterinarian.
Your dog depends on you to notice those subtle changes. With awareness, love, and early action, you can help ensure your furry friend stays as healthy and happy as possible.
