A tumor on your cat’s anus

How bad is that?

In this article we discuss how to recognize a tumor on your cat’s anus and what symptoms you may notice. We tell you which tumors may be involved and which of them are cancer. We also explain to you how your vet can diagnose which tumor your cat has on its anus and what the possible treatment is in this case. This depends on the type of tumor. But in fact, unfortunately, they all have to be surgically removed to achieve healing. Since most cats are a bit older, not everyone opts for treatment. We hope to give you more clarity with this article.


Cat with an anus tumor with a sign over his behind that says "censure".

How do you recognize a tumor on your cat’s anus?

Most people don’t really find it difficult to recognise the fact that a tumor is growing on their cat’s anus. They are usually tumors with a clear border, where you can see that they emerge from the surface of the anal skin. This lump may still have normal skin over it, but it may also be a tumor that grows through the skin and which you then recognize as a flesh-like bump without skin. An open wound, so to say. In addition, polyps also occur in a cat’s anus. These are a kind of wart-like growths that can spread out through the anus opening.


What tumors occur in a cat’s anus?

We see various tumors on a cat’s anus. Fortunately, they are generally not very common. There are benign tumors and malignant tumors. These malignant tumors are cancer. We see polyps most often as benign tumors. A polyp is an overgrowth of cells that come from the mucous membrane in the anus. But a perianal adenoma is also benign. This tumor grows from the perianal glands around the anus and is mainly caused by testosterone. We mainly see this tumor in unneutered male cats of senior age.

Malignant tumors, i.e. cancerous growths, include anal gland adenocarcinoma, squamous cell carcinoma and mast cell tumors. The first is a tumor that grows from the anal gland tissue, the second grows from the mucous membrane, and the last is a cancerous tumor that arises from mast cells. These are cells that are related to your cat’s immune system. They can appear anywhere on your cat’s body.


Symptoms of a tumor on your cat’s anus

Usually there are not many special symptoms to be noticed. Your cat obviously has a lump around his anus. In addition, your cat may feel a little irritation in its anus. In some cases, a tumor can become infected, causing you to see a smelly, purulent wound. Your cat will lick its anus in that case more or rub the ground with his buttocks. We also call this scooting. If the tumor on your cat’s anus is already quite large, your cat may also have some difficulty passing stools and become constipated. You will then see that his anus region will protrude further and we do not mean the tumor itself.


How do you know which type of tumor is on your cat’s anus and whether it is harmful?

Unfortunately, you can’t find that out yourself. You need the help of your vet with this. This can use a needle to remove some cells from the tumor on your cat’s anus and place them on an microscope slide. These cells can be sent to a laboratory, where they will investigate which types of cells they see. Based on the type of cells, they can tell whether it is a malignant or benign tumor. And what type of tumor it is. The lab also often indicates in the result how aggressive this tumor appears to be. In other words, whether it grows very quickly and whether it will easily cause metastasis.



The tumors that occur in a cat’s anus are in most cases surgically removed if this is possible. For perianal gland tumors in unneutered male cats, it is usually sufficient to castrate them. They will usually disappear on their own afterwards. Polyps are generally quite easy to remove through a small incision. The other types of tumors are malignant and will need to be removed more aggressively and, if the owner wants this, it is better to also give these cats chemotherapy to suppress the cancer. In addition, an X-ray is often taken of the chest cavity to see if there are any signs of metastases. In that case, surgery unfortunately no longer makes much sense.


Cat with a tumor on its anus doesn't want to visit the vet so it holds up a sign that says "no way!!!"

When do you visit the vet?

It is important that you go to the vet as soon as possible if you see a tumor on your cat’s anus. The smaller the tumor is, the easier it is to remove surgically if you wish. And also the smaller the chance of metastases. Your vet will first investigate what the tumor on your cat’s anus is and then make a treatment plan together with you as the owner. Not everyone wants chemotherapy or surgery.

What else can you do if you decide not to have your cat operated?


Unfortunately, there is no way to make the tumor disappear in a cheap and low-stress way for your cat other than through surgery. But you can of course support your cat for the rest of its life without removing the tumor. We call this palliative care. What your cat needs obviously depends on his complaints. Does he have difficulty passing his stool past the tumor? Then you can give him a laxative. This makes his stool much softer and allows it to move better past the tumor.


constipation relief cat

Honey ointment

When your cat has a tumor on its anus that grows through tissues, a kind of open wound is created. You can imagine that such a wound quickly become infected because it’s close to the anus. But normal skin bacteria can also infect the tumor wound. It is therefore wise to rub his tumor with a bactericidal ointment. It is best to apply iodine ointment, but since your cat will lick it up, he will need to wear a collar since this ointment will cause diarrea. And we don’t think it is in the interest of your cat to let him walk around with a collar for the rest of his life. That is why we recommend applying honey ointment to it 3 times a day. This also has an antibacterial and wound-care effect. But of course the wound will never close again because it does not dissolve the tumor.


honey ointment


If your cat is also in a lot of pain, you can ask your vet if your cat can be prescribed a painkiller. They probably won’t make a fuss about it if you have already been there to make a diagnosis. If they don’t want this you can also use Aspirin 81mg tablets. Give your cat half of a tablet once every two days. This is not as strong as the painkiller that your vet can prescribe, but is most of the times sufficient in reducing its pain. Hopefully your cat will have a good quality of life in the near future and you won’t have to say goodbye to him for a while. All the best!