While cats develop cancer at approximately half the rate as dogs, it’s still a scary diagnosis for any cat owner to receive. Fortunately, with a little bit of understanding, the good news is that cancer can sometimes be prevented in our feline friends, and there are also an array of treatment options to help preserve a cat’s quality of life if they do receive a cancer diagnosis.
Here are 5 things all cat owners should know about feline cancer.
1. There’s One Type of Cat Cancer That’s Most Common
And that’s lymphoma, a disease that causes cancerous tumors in a cat’s lymph nodes and can present itself in their bone marrow, liver or spleen, gastrointestinal tract, skin and eyes. According to Dr. Joyce Login, veterinary medical lead of pain, oncology, and specialty at Zoetis, lymphoma can affect cats of any age, sex, or breed. Surprisingly, it typically impacts younger cats (those under six years of age).
Although lymphoma is something that also affects humans, it isn’t necessarily going to manifest the same way in a cat. “Feline cancers might share similar names with people, such as lymphoma, but biologically, they can behave very differently,” explains Dr. Lauren Demos, board member and past president of the American Association of Feline Practitioners (AAFP).
When it comes to preventing lymphoma, cat owners can take one important step—ensure that their feline friend is vaccinated for the Feline Leukemia Virus (FeLV); second only to trauma as the leading cause of death in cats, the virus is the greatest cause of a cat developing lymphoma later in their lives.
2. There Are Some Symptoms to Watch Out For
Dr. Brooke Britton, medical oncologist for BluePearl Veterinary
Partners in New York City, notes that other common cancers in cats include oral cancers like squamous cell carcinoma and fibrosarcoma, a cancer of connective tissues. Symptoms will vary depending on the type of cancer, but there are some things to watch out for when it comes to early cancer detection in cats.
“Signs of cancer can range from vague to obvious lumps and bumps of the skin,” Demos explains. “Some of the more subtle signs can include gradual weight loss, vomiting (including hairballs) and anorexia, along with subtle behavior changes, like new sleeping spots or sleeping more.”
Lymphoma, in particular, can occur anywhere within the body where lymphocytes reside, however the most common presentation of lymphoma in cats is within the gastrointestinal tract, Britton notes. “These cats may be losing weight over time and show signs of stomach upset, such as loss of appetite, vomiting and/or diarrhea,” she adds. “A myriad of other problems can occur secondary to lymphoma, and may include organ dysfunction or failure, lethargy, infection, bleeding, fatigue, and shortness of breath.”
3. Cancer Isn’t Caused by Cat Food
According to Britton, there are numerous misconceptions regarding the reasons cats develop cancer in the first place, including the impact of feeding canned versus dry food or carb-free versus carb-inclusive diets. “In reality, cancer is a complex disease with several different genetic and environmental and other factors at play, and the cause of cancer in any one individual cat is never fully known,” she says.
Just as in humans, however, there are a host of genetic and environmental influences that can affect a cat’s risk factors for cancer. Britton notes that in addition to developing diseases like FeLV or Feline Immunodeficiency Virus (FIV), exposure to second-hand tobacco smoke, obesity, and exposure to sunlight in lightly-pigmented cats are all believed to be potential causes.
“We know a lot less about definitive causes of cancers in cats than we would like. There are some cancers that are likely driven by genetic mutations, such as mast cell tumors, but little work has been done in this species compared to canines,” Demos adds. “Viruses are implicated in others, such as papillomavirus in squamous cell carcinomas, which is similar to humans.”
4. Chemotherapy Doesn’t Affect Cats the Same Way as Humans
Understandably, most people have a negative perception of the side effects of chemotherapy or chemotherapy-like drugs, and so when it’s recommended as a treatment for feline cancer, cat owners are often concerned that their cat's quality of life will be negatively affected—or that the stress of coming to the veterinarian more frequently for treatments will outweigh any benefit of therapy. “In reality, the vast majority of cats tolerate regular vet visits and chemotherapy very well, with significantly fewer and much less severe side effects reported than people receiving these treatments—if they experience side effects at all,” Britton says.
Many cat owners may also be concerned about the age of their pet and their ability to tolerate cancer treatments. “The majority of patients treated by veterinary oncologists are middle-aged to geriatric, and in most cases, older pets tolerate treatment just as well as their younger counterparts, and have every chance of responding to therapy as a younger cat would with the same condition,” she adds.
Login adds that, unlike many humans, cats also won’t lose their hair as a result of the chemotherapy, and that there are medications that can be offered to help with any other side effects, such as vomiting. “Cats don’t have hair...they have fur,” she explains. “However, there is a chance that they will lose their whiskers.”
5. It’s Not a Death Sentence
According to Login, probably the biggest misconception about cancer—for both humans and their animal friends—is that it’s a death sentence. However, modern technology and advancements in treatment have made it so that is no longer the case. “It depends on the type of cancer, but many forms are more treatable today than they ever were before…and technology advances so rapidly that if a particular treatment can’t be offered today, it will probably be available next month,” she says.
Britton notes that treatment options for cats vary widely depending on the type and extent of cancer, as well as any other medical issues the cat may have. Generally, the therapeutic options for cats with cancer include surgery, radiation therapy, immunotherapy (such as anti-tumor vaccination), both injectable and oral chemotherapy, targeted therapies that impact tumor signaling, and anti-inflammatory and other supportive medications.
“Specific treatments depend highly on the type of cancer. But cats with cancer generally have the same treatment options as people,” Demos says.