No one wants to hear the word “cancer” about a loved one—human or furry. However, cancer is a common disease. The Cornell Feline Health Center estimates cancer affects 30-40 percent of cats.
These numbers may send chills down your spine if you love your kitty. The good news? Cancer isn’t always fatal, but early detection is often critical. That’s why it’s important to know about cat cancer symptoms and signs.
“Early detection gives a better prognosis for treatment,” says Leslie W. Gillette, DVM, a veterinarian at Chewy. “Just like humans who screen regularly for conditions like prostate, colon, and breast cancer, it is important to pay attention to your cat’s overall health and any changes to their physical appearance or daily routine.”
Our cats don’t make noticing flags easy on us, though.
“It is important to understand the warning signs of cat cancer as our feline friends are notorious for their ability to hide clinical signs of illness from their owners, often until the illness is moderate to severe,” says Patrick Mahaney, VMD, a veterinarian and advisor for Dr. Treat, a pet health and wellness startup based in San Francisco.
Regular check-ups with your vet can help them flag any potential concerns. However, knowing your cat—and common cancers and their symptoms—can help you fill the gaps between wellness checks.
Related: The 10 Best Exercises for Your Cat, According to Veterinarians
What Is the Most Common Cancer in Cats?
Lymphoma. “It arises from uncontrolled growth of a type of white blood cell called lymphocytes,” explains Rebecca Greenstein, B.Sc, DVM, a veterinary medical advisor for Rover.
There are a few types of lymphoma, Dr. Gillette says. Intestinal lymphoma is the most common, accounting for about half of cases. Mediastinal lymphoma is less common and occurs in the chest. Lymphoma can also affect the kidneys (renal), nasal passages or multiple organs at once (multicentric).
“Treatment typically involves chemotherapy or radiation therapy, and sometimes surgery,” says Robert Gonzalez, DVM, the regional medical director for Small Door Veterinary. “Prognosis varies depending on the type and location of lymphoma.”
Related: Cat Retirement Village in the U.K. Comes with Most Adorable ‘Mini Cottages’ for Senior Kitties
7 Other Types of Cat Cancer
1. Soft tissue sarcomas
Soft tissue sarcomas come in many forms, Dr. Gillette notes. The common thread?
The cancers “originate in the body’s connective, muscle, nervous and fatty tissues,” Dr. Gillette says.
Soft-tissue sarcoma may be diagnosed as:
- Leiomyosarcoma. Dr. Gillette says this cancer affects the stomach and intestine and can be painful and aggressive. It’s relatively uncommon.
- Liposarcoma. Dr. Gillette says this cancer develops in fatty tissues. “[It’s] very uncommon with low metastatic potential but may be related to Feline Leukemia vaccine injections.”
- Rhabdomyosarcoma. Also rare but aggressive, Dr. Gillette explains that rhabdomyosarcoma is a tumor that frequently develops in the heart of oral cavity tissues such as the tongue. However, it can spread to other organs like the lungs.
- Neurofibrosarcoma (schwannoma). Dr. Gillette says this cancer originates in the tissues surrounding and protecting the peripheral nervous system. It doesn’t spread but often returns after treatment, including surgical removal of the mass.
- Fibrosarcoma/vaccine-site sarcoma. This aggressive form of cancer develops from connective tissues like the oral cavity or at injection sites. In the case of the latter, it’s known as injection-site sarcoma. “Newer generation cat vaccines have removed the offending components, making vaccine-associated sarcomas much rarer these days,” Dr. Greenstein says.
2. Squamous cell carcinoma
Dr. Gillette says this cancer may develop on a cat’s face, eyelids, ear tips or inside the mouth.
“These tumors typically require surgical excision or debulking (removing as much of the mass as possible) depending on the size and location of the mass, but chemotherapy and radiation can also be used after surgery as follow-up treatments,” Dr. Gillette says.
Dr. Gillette says some common clinical signs include oral pain, bleeding gums, tooth loss, mouth odor and difficulties chewing food.
3. Mast cell tumors
Dr. Mahaney explains that mast cells are a type of white blood cell.
“Mast cell tumors are cancers of mast cells that commonly arise in association with some form of allergic or inflammatory trigger,” Dr. Mahaney says. “Mast cell tumors can have a good prognosis if they are detected early [and]…surgically removed with wide margins and if other evidence of cancer elsewhere in the body is not found.”
4. Mammary adenocarcinoma
Dr. Gillette says this cancer isn’t as common now that spaying is routine in our female feline friends. However, it’s sadly still one of the most frequently-diagnosed cancers in kitties.
“It is still the third most common in cats over 10 years old,” Dr. Gillette says. “This type of cancer primarily affects female cats who were spayed later in life or never spayed.”
Surgery to remove the solitary lump, entire mammary gland or chain of glands can treat this cancer. Left undetected, this cancer can spread to other organs and glands like the lungs and liver and become more challenging to treat, so early diagnosis is critical.
“These tumors are usually identified as firm, lumpy masses with irregular margins, which may be painful to the touch, located within the mammary tissue or underneath the nipple and may include more than one mammary gland or an entire chain,” Dr. Gillette says.
5. Chondrosarcoma/Osteosarcoma
Dr. Gillette says this cancer is relatively uncommon in cats but affects the bones.
“Clinical signs often include solitary swelling at the site of the growth, pain when the mass is touched, lameness or difficulty walking if long bones are affected, and may increase the risk of pathologic fractures once the health of the bone is compromised by the invasion of cancer cells,” Dr. Gillette says.
6. Meningioma
“Meningioma is a type of cancer that originates in the meninges, which are the layers of tissue separating the skull and the brain,” Dr. Mahaney says.
The chances of survival for a cat with Meningioma vary greatly.
“The prognosis depends on invasiveness and location of the tumor,” Dr. Gillette says.
7. Hemangiosarcoma
Dr. Gillette explains that hemangiosarcoma “originates from the endothelial cells that line the body’s blood vessels, most commonly developing in the spleen, liver, or on the skin.”
Sadly, this one has a poor prognosis.
“[It’s] very aggressive and has been known to metastasize to other organs, including the brain, lungs and heart,” she says.
8. Iris melanoma
Iris melanoma starts in a cat’s melanocytes, “which are the cells that produce melanin, the pigment responsible for the coloration of skin, eyes and hair,” Dr. Gillette says.
It is highly metastatic, which means it spreads quickly.
Related: Photographer Documents Cat’s Aging Process and the Result Is Incredible
Cat Cancer Signs and Symptoms Most Owners Miss
1. Lumps and bumps
Some cats don’t like to snuggle, making it hard for pet parents to detect lumps and bumps. Other times, they develop in easy-to-overlook spots.
“Some bony and soft tissue tumors will present as a new, unusual mass on the body or extremities or in the mouth,” says Dr. Greenstein.
2. Unexplained weight loss
If your kitty wasn’t placed on a weight loss plan but is dropping pounds, it’s a flag.
“It may be due to oral pain, nausea [or] tumors of the digestive tract,” Dr. Gillette says.
Dr. Gillette explains that these issues can make a cat eat less or interrupt the digestive process in a way that causes a pet’s nutritional needs to go unmet.
3. Loss of appetite or difficulty swallowing
Often the predecessor to unexplained weight loss, it’s worth a vet visit if you notice your cat is suddenly and consistently eating less.
“It can be from nausea or physical irritation or secondary damage to vital organs,” says Dr. Greenstein. “In the case of oral cancers, the tumors may also interfere with the ability to eat.”
4. GI Upset
This symptom typically presents as vomiting or diarrhea. Vets share that this sign can be a symptom of numerous cancers, but Dr. Gonzalez says it’s often related to gastrointestinal cancers.
GI issues can also be signs of other conditions, including less benign ones, so consulting a vet is vital to clarifying.
5. Urinary issues
Like GI upset, these urinary problems could have various reasons. However, sometimes, blood in the urine or challenges urinating “can be linked to bladder or urinary tract cancers,” Dr. Gonzalez says.
6. Shortness of breath
If a cancer has developed or spread to the lungs, Dr. Greenstein says it can lead to problems breathing.
“Fluid can also build up in or around the lungs as a result of certain forms of cancer,” Dr. Greenstein says.
What To Do if You’re Concerned About Your Cat’s Health
Speak with your feline friend’s vet.
“Remember that a veterinarian is the best resource for evaluating your cat’s health and providing guidance on cancer prevention and management,” Dr. Gonzalez says. “Early detection and prompt treatment can make a significant difference in your cat’s well-being.”
Next:Â The Earliest Signs of Cancer in Dogs That Most Pet Owners Miss, According to Vets
