Spotting and Understanding Melanoma in Cats and Dogs

Spotting and Understanding Melanoma in Cats and Dogs

Health & Safety

With summer and the hotter weather just around the corner, it's that time of the year when people start to bring out sunblocks to help reduce the risk of skin cancers. However, you need to think about your beloved pets too because leaving them out in the hot sun could mean they develop sun-induced tumours called melanoma. Just because your pet whether it's a dog, cat, rabbit or other four legged pet has a furry coat, does not mean they are not susceptible to being adversely affected by the sun and one of the things you need to watch out for is skin cancers.

Melanoma in cats and dogs doesn't look the same as it does in people but it is just as dangerous and deadly. Below are a few signs that may help you recognise if this nasty disease has taken a hold and help you differentiate whether it is indeed melanoma or some other condition that looks very similar. With this said, if you notice any strange marks on your pet's skin, you should take them to the vet as soon as you can.

Has Your Pet Developed Spots?

If you notice any dark spots appearing on your pet's skin there could be a problem which your vet would need to have a look at. The good news is that this type of skin melanoma is relatively rare in cats and dogs and you have to bear in mind that a few other common skin conditions can look very similar to melanoma.

One example is a condition known as "lentigo simplex" which Orange Tiger cats are to prone to and is where pigmented areas appear on the edges of their gums, nose, eyelids and lips. These are benign lesions that do not need any sort of treatment and which do not get any worse or turn into melanoma.

There is another skin condition that's non-cancerous and which is often confused with melanoma in dogs which is an oval or sometimes round, flat and pigmented area of skin that often appears after the dog has suffered some sort of skin infection known as a "macule". Before the pigmentation sets in, you may find the skin is red and itchy but these lesions are not cancerous but your pet would need to be put on a course of antibiotics to clear up the condition. The areas of the body macules typically appear are on a dog's tummy where there is less hair.

However, if you are unsure you should take your pet to the vet for a thorough examination so that any other conditions can be eliminated and a correct diagnosis can be made.

It Can Be Hard to Detect Melanomas

Unlike in humans where a melanoma may be easy to feel or spot, on dogs, cats and other pets it can be hard to see a melanoma due to the fact their bodies are covered in fur. However, the most common melanoma in dogs are oral and to a lesser degree the same can be said of cats. Unless your pet feels comfortable with you opening their mouths to examine them, you should leave this to a vet to do which is why it is so important for pets to have regular health checks. However, if you notice your pet is suffering from a bad case of halitosis, this could be a sign there is something very wrong.

If your pet allows you to examine the inside of their mouths and you notice any black and raised areas on their gums that are bleeding, then this could be an oral melanoma. You should take your pet to the vet as soon as you can so they can sedate your cat in order to take a close look at the problem. The vet may want to do a biopsy in order to make a correct diagnosis and then recommend surgery or radiation therapy. These days, however, there's a vaccine to treat oral melanoma tumours but you need to bear in mind that these are treatments and not cures.

Feline Ocular Melanoma

This is one of the hardest feline melanomas to spot because it first attacks the iris which is the coloured part of your pet's eye. The melanoma may first appear to be a simple freckle on their eye but as time passes, this freckle gets larger and larger covering more of the iris as it does. If you do notice a dark spot in your cat's eyes, you should make an appointment and take your pet to see the vet who would recommend your cat sees a veterinary ophthalmologist to determine whether the melanoma is malignant or not.

Should the results come back as the melanoma being malignant, the best course of action would be to have your cat's eye removed as this is the only way of preventing the tumour from spreading and although it may be a hard decision to make, having your pet's eye removed means they will be able to live that much longer than if the eye stays in.

A Broken Nail Could be a Melanoma

Another hard to spot melanoma that affects dogs is one that masquerades as a broken nail. The actual melanoma develops at the edge of the toe where the nail begins and as it grows it weakens the nail which then snaps off for no reason. The toe swells and is very painful which could be a clear indication of a melanoma forming. Your vet would want to take an X-ray which would reveal if indeed this is the case and would typically recommend the toe being removed to prevent this nasty tumour from spreading and thus prolonging your pet's life.


If you are at all worried about any sort of skin condition your cat or dog may suddenly have developed, you should consult your vet immediately because melanoma is a very aggressive form of cancer that needs to be caught early and then treated accordingly. Veterinary medicines have come on in leaps and bounds but more research needs to be done into melanoma so that treatments can be improved with the end goal being to prolong the lives of many pets including dogs and cats.

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