What are sebaceous cysts?
Sebaceous cysts are swelling underneath the skin caused by clogged oil glands. They can be found on dogs of any age and breed and are fairly common.
All dogs have sebaceous glands (sweat glands) that secrete keratin. Sebaceous glands play an important role in keeping your dog’s coat sleek and shiny. When you brush your dog, it prompts these glands to release the keratin oils that moisturize your dog’s skin.
But, issues occur when the hair follicles of these sebaceous glands can get blocked, which causes a buildup of oil secretions. When the sebaceous gland remains blocked, the natural secretions have nowhere to go, prompting a cyst to form. Sebaceous cysts are swelling in the skin caused by a clogged sebaceous gland.
Many sebaceous cysts are benign, but they can interfere with your dog’s natural movement. They are also prone to infections.
Sometimes these cysts can be a sign of an underlying condition, like cancer. Dogs can get a variety of skin cancers, including malignant melanomas, mast cell tumors, squamous cell carcinomas, and more.
Sebaceous cysts are also known as epidermoid or epidermal inclusion cysts. However, they aren’t the most common cysts dogs can have. Follicular cysts are more common in dogs. Follicular cysts are lumps that form in the sacs under hair follicles.
Common places for sebaceous cysts
Sebaceous cysts can occur anywhere but are most commonly found on the head, neck, ears, and anus.
Sebaceous cysts are also found at pressure points like hips and elbows.
Causes of sebaceous cysts
Genetic predisposition. Some breeds, including schnauzers and Yorkshire terriers, could be genetically predisposed to developing cysts.
Follicle opening blockage. Sebaceous cysts are caused by clogged glands. This could be because of oil trapped in the glands, but injuries, dirt, and infections can also lead to clogged pores, creating cysts.
Injury or trauma. Sometimes sebaceous cysts can form because of trauma.
Age. There are also different types of sebaceous cysts that can be found in older dogs or specific breeds.
Sebaceous gland adenocarcinoma are malignant cysts found in middle age to older dogs. These malignant cysts are more likely to be found in male dogs. They’re also more likely to happen in breeds like Cavalier King Charles spaniels, cocker spaniels, or Scottish, Cairn, or West Highland white terriers.
Sebaceous gland adenoma (a rare, benign lesion) are found in older dogs, typically on the dog’s head. Some breeds are predisposed to sebaceous adenoma, including Samoyeds, Siberian huskies, coonhounds, English cocker spaniels, and Alaskan Malamutes.
Sebaceous cysts symptoms
- Raised bump or lump
- Hair loss around the lump
- Fluid discharge
- Multiple bumps
The appearance of sebaceous cysts in dogs can vary, but in general they range from half an inch to approximately two inches (though cysts this large are rare). That’s the size of a blueberry compared to the length of a credit card. On average, our DVM Dr. Erica Irish sees cysts from five to 10 millimeters.
The cysts typically feel soft or firm and moveable on top of a dog’s skin or inside the skin layers. Cysts may look like pimples, warts, or slightly translucent nodules.
Don’t squeeze or move these cysts. Popping a cyst can spread the cyst’s contents into the surrounding tissue, which can result in swelling, infection, or inflammation.
When to visit a veterinarian about sebaceous cysts in dogs
While sebaceous cysts don’t require an emergency vet visit, they must be checked by a veterinarian.
Dogs need to have their cysts checked out for the same reason that humans have moles and breast lumps checked out: while the cysts could be benign, there’s always a chance that it could be something serious.
Cysts can also interfere with a dog’s normal movement and impair them. A cyst on a paw pad, leg, or joint can interfere with their ability to walk. A cyst on an eyelid (known as meibomian gland adenoma) can interfere with their ability to blink or cause excessive blinking.
While most cysts are generally slow growing and aren’t harmful, cysts that grow quickly are abnormal. They can also rupture and lead to infection.
It’s also important to go to the vet because there are some types of cancers that may look like innocent cysts, but are actually cancerous tumors.
👉 If you think your dog has a sebaceous cyst, make an appointment with your veterinarian.
Diagnosis of sebaceous cysts in dogs
Veterinarians will begin by giving your dog a full physical examination. They will access the size, appearance, and location of any cyst, and check to determine if there are multiple cysts.
Your veterinarian has a few options to diagnose the bump.
Fine needle aspiration. Your veterinarian may use a fine needle aspirate to take a sample of the raised bump with a needle and syringe. The collected cell sample can then be observed under a microscope to determine if the new lump is a cyst, tumor, or benign growth. However, fine needle aspiration may not be enough to make a definitive diagnosis. Vets will sometimes send these cells to lab specialists for more information.
Tissue biopsy. Your veterinarian may choose to do a biopsy for a more accurate diagnosis. A biopsy is a surgical removal procedure where your veterinarian removes tissue so it can be sent to histopathology and analyzed. For small bumps, your veterinarian will put your dog under local anesthesia and mild sedation. Larger biopsies will require general anesthesia. Histopathology is an effective way to determine what the new lump on your dog’s skin means. Biopsies can rule out other skin conditions, like lipomas or viral warts like papillomas.
Your veterinarian will also check for any infections or inflammation and treat that as well, sometimes with medication.
Treatment of sebaceous cysts in dogs
Sebaceous cysts aren’t something that you can treat at home because the underlying condition causing the cyst needs to be investigated.
If it’s a new lump, your veterinarian may choose to observe and delay treatment until there’s further growth. Cysts are often benign, so treatment may not be needed. As long as the cysts aren’t bothersome, your veterinarian may prefer to keep an eye on the area.
Your veterinarian may decide to later remove the cyst and treat it with medication. Veterinarians may remove cysts through surgery. If there are multiple cysts, removal may take longer.
It’s possible that new sebaceous cysts may appear in the future, even after existing sebaceous cysts are removed.
However, if the cyst is cancerous or a malignant adenocarcinoma, veterinary oncologists may start your dog with chemotherapy, radiation, and surgery.
According to PetPlan, the average cost of unexpected veterinary care for dogs and cats is between $800 and $1,500. The average cost of removing a sebaceous cyst can vary from $75 to $250, but the price can increase if there are multiple cysts, according to Wag Walking. The site also reports that the cost of a less invasive biopsy can cost between $400 to $800, while more invasive biopsies can cost up to $2,500.
👉 Never try to pop your dog’s cysts at home. This could cause skin infections or inflammation.
Recovery from sebaceous cysts in dogs
Your beloved canine may need to wear a cone or Elizabethan collar to prevent them from licking or biting the affected areas as they heal. You may need to give your dog antibiotics or apply any topical medication your veterinarian prescribes. You will need to check the wound’s location for redness and bleeding, and check in with your veterinarian if it doesn’t heal. While the wound heals, dogs are not allowed to bathe and may be put on strict rest.
If no surgery is needed, you may be advised to keep the area clean and to observe the area for growth.
If the cysts are cancerous, recovery may be longer for obvious reasons.
How to prevent sebaceous cysts in dogs
There’s no way to effectively prevent sebaceous cysts, especially since genetics may determine which breeds are more likely to get them.
One of the best ways to monitor your dog’s health is also one of the simplest: brush your dog frequently. Frequent brushing not only keeps your dog’s skin and coat healthy, but stimulates the sebaceous glands to release keratin. Stimulating the sebaceous glands can help prevent cyst growth as it helps reduce the chances of these glands becoming clogged.
In general, brushing your dog is a good way to keep in check with their overall health.