Cystic Biopsy in Cats

Biopsy is a procedure that involves taking a tissue or cell sample from a part of an animal’s body so that it may be tested for disease. In cystic biopsy, a tissue sample is taken from a cyst located on the animal’s body. A cyst should not be confused with a tumor. While both appear as masses, a cyst is typically filled with air or bodily fluid, while tumors originate within the tissue from which they are located. Tumors and cysts may be benign or malignant; however, most cysts are benign. Owners should ensure that any new lump, tumor, or cyst is inspected by their cat’s trusted veterinarian as soon as possible, especially since cysts and tumors look similar.

The exact procedure steps of cystic biopsy may vary depending on the type of biopsy performed. Fine needle aspiration is typically not used for cysts, as cytologic examination will not aid in making the diagnosis. The most common biopsy methods for cysts are biopsy punch, incisional biopsy, and excisional biopsy. The technique used will vary based on the location of the cyst. The procedure steps for all three methods are outlined below.

Biopsy Punch

1. The cat will be given local anesthesia.
2. The vet will use a biopsy punch to take a tissue sample from the cyst.
3. If more than one cyst is present, the vet will repeat the process for each cyst.
4. This sample(s) will be sent to a histopathologist for examination.

Incisional Biopsy

1. Local anesthesia will be administered to numb the cyst and surrounding area.
2. The vet will incise the cyst and remove a portion of it.
3. This process will be repeated for all cysts.
4. This sample(s) will be sent to a histopathologist for examination.

Excisional Biopsy

1. The cat may be anesthetized with local or general anesthesia.
2. The vet will remove the cystic mass.
3. Only one cyst may be removed if there are several present. The number of cysts removed will vary based on the vet’s preferences and the overall health of the cat.
4. The full mass(es) will be sent to a histopathologist for examination.

Histopathology is considered more accurate than cytology for diagnosing condition. With cytology, biopsies are typically taken via fine needle aspiration, and the cells are examined using a microscope. Examination of cystic tissue samples or entire masses must be carried out by a certified veterinary pathologist, since cytology is not very useful for diagnosing cysts. Histopathologic biopsy will give a more accurate diagnosis, and the practicing pathologist will be able to tell if the entire mass was removed. Histopathologic examination is also more effective for making predictions about the animal’s prognosis and the course of underlying disease.

Cats will not need to recover from biopsy since it is a minimally invasive procedure used for diagnostic purposes. The recommended treatment for cysts will vary based on the underlying cause. Feline acne will generally clear up on its own, but chronic feline acne may be treated with medication. Some cysts are treated with medications, while others are treated with laser surgery. Some cyst will not require treatment at all, particularly dermoid cysts that are not causing pain or other issues for the cat. If dermoid cysts affect a cat’s eyesight, they will be removed surgically.

The cost of cystic biopsy will vary based on standards of living and the type of biopsy performed. The average cost of a cystic biopsy is approximately $100.

Because cystic biopsy is a common and minimally invasive procedure, there are very few complications associated with it. Cats may react to local or general anesthesia. Should a reaction occur, the practicing vet will treat it accordingly.  Cats may be evaluated for anesthetization prior to the procedure if the owner has any concerns about the cat’s safety.

Cysts are not generally life-threatening. However, if a cyst is left untreated, the risk of cystic rupture increases. Cystic rupture can cause infection and exacerbate the underlying condition. Owners should seek immediate veterinary attention if they spot any kind of lump on their cat.

Some cysts are difficult to prevent, particularly those that are associated with congenital defects or inflammation of the hair follicles. Owners should make sure their cats do not engage in activities that may cause trauma to the hair follicles, or trauma to any tissue that may result in tissue necrosis.