Petting our cat is not only a pleasurable experience for both the animal and for us, it is an important practical resource in the care of our cat’s well-being. It allows us to enrich the affective bond we have with our furry friend and gives us the opportunity to observe certain clinical symptoms. A subcutaneous lump can be one of the most worrisome symptoms, as it may imply the presence of cancer. However, there are many types of cat cysts that can give rise to a lump or tumor, without being malignant.

These are the most common types of cat cysts, causes and treatments


Lipomas are also known as fatty tumors. This is because they are caused by the overgrowth of fat cells (the cells that make adipose tissue grow). These masses of mesenchymal origin usually develop in the subcutaneous tissue. Generally, these lumps have a spongy, soft, firm consistency and may appear singly or in clusters. They are mobile, meaning that they can move on palpation.

Lipoma cysts are benign, but should be removed immediately. This is because their growth rate is usually relatively rapid and can cause discomfort or compromise the function of certain tissues. They do not have the ability to metastasize to other nearby or distant tissues.

Certain breeds are more predisposed to develop fatty cysts. Siamese-type cats are particularly prone to developing lipomas, but generally the cats most at risk for developing lipomas are older, neutered cats.

Treatment of feline lipomas

Excisional surgery (removal of tissue) is the method of removing lipomas in cats. After veterinary evaluation, you may be able to choose surgical options or wait to see if the lipoma develops problematically. If you decide to wait, it is important that lipomas be checked regularly to determine if they need to be removed.

We should keep in mind that the larger the lipoma, the more scar tissue the cat will have once it is operated on. The size may also prolong the cat’s recovery time.

False cysts

Although neoplasms are due to an overgrowth of cells, this overgrowth can have several causes. A common reason is an inflammatory process that has several causes. Allergies are a common cause of inflammation, although the resulting inflammation usually takes the form of hives, rather than a cyst.

Although not very common in cats, trauma can result in a cyst. These are sometimes referred to as false cysts and differ from true cysts. They are caused by hemorrhage or trauma that does not resolve properly. Instead of dissipating, the fluid inside the cyst accumulates because there is no secretory lining. The fluid is caused by liquefied dead tissue. If the false cyst is caused by accumulation of blood, it will have a dark appearance.

Treatment of false cysts in cats

In many cases, the swelling caused by the false cyst will subside on its own. It should usually go away, although some discoloration may remain on the affected skin. If the false cyst causes problems for the cat, it can be removed by surgical excision.

Dermoid cysts

Dermoid cysts are another type of subcutaneous neoplasm in cats that occur due to abnormal cell growth. They are genetic in origin and are considered rare in cats.

Dermoid cysts not only contain an overgrowth of cells, but can even cause the growth of mature solid tissues. These can include hair, teeth and bones. In humans, they are often associated with ovarian cysts, but there is not much evidence of this in cats. They are caused by a defective closure of the epidermal layer of the skin, becoming isolated in the dermis or subcutaneous tissue.
Treatment of dermoid cysts in cats
After diagnosis, the only treatment available is surgical removal. Although relatively simple, care must be taken to do the correct dissection of the cyst. This will need to be done very carefully because we want to prevent the cyst from returning.

Sebaceous cysts

One of the most common types of feline cysts are sebaceous cysts. These are fluid-filled lumps that may ooze, especially if they receive trauma. They can have a similar appearance to skin tags, another type of benign tumor.

The reasons sebaceous cysts develop are due to a problem with the hair follicle, often because they become clogged with sebum or other material. When this happens, the cat’s immune system attempts to isolate the damaged follicle, resulting in fluid encapsulation and subsequent cyst.

Although not caused by infection, they can become infected if they rupture and bacteria are allowed to enter. This is often due to them hitting when the cat is moving or even when the cat is grooming. Sebaceous cysts in cats can develop anywhere on the cat that has hair follicles. They should be diagnosed by a veterinarian in case they are mistaken for a different type of cat cyst.

Treatment of sebaceous cysts in cats

It is important to note that sebaceous cysts in cats are benign. They usually only cause a problem if they become infected, but in many cases they can be ignored. If the cyst continues to grow and fill with fluid, it can enlarge and rupture. If the veterinarian decides to remove the cysts, a more aggressive treatment of surgical removal will be possible, but is considered minor surgery.

Malignant cysts

It is important to note that the cysts themselves are not cancerous. They are not malignant and do not metastasize. However, there are types of cat cysts that harbor genetic material that can develop into malignant tumors that can then spread to the rest of the body. These types of cysts can appear subcutaneously, in which case we can feel them when we pet our cat. They can also develop internally, which is more difficult to observe.

Treatment of malignant cysts in cats

Treatment will depend on the severity of the cancer. It will require surgery, chemotherapy, radiotherapy or some combination of these. In cases of metastasis, the prognosis will be worse. In some cases, this will result in euthanasia of the animal.

If you notice any lump on your cat’s skin, do not hesitate to come to our clinic in Barcelona so that we can examine and diagnose its state of health as soon as possible. Call us at 932 460 805 or contact us through the web form.