10 Misconceptions About Pets and Cancer

Misconceptions abound about cancer and pets, and many people apply what they know about human cancers to animals. Although there are some similarities, many human cancer traits—including appearance, treatments, side effects, and prognosis—differ drastically. We separate fact from fiction, so you can make the best decisions regarding cancer prevention, diagnosis, and treatment for your furry friend.

Myth #1: Skin Masses in Pets Are Not Cancerous

Many masses on or under your pet’s skin, including sebaceous adenomas, histiocytomas, and lipomas, are noncancerous. However, pets can be affected by many forms of cancerous (i.e., malignant) tumors, including squamous cell carcinomas, melanomas, and mast cell tumors, that present as skin masses, but are particularly aggressive cancer types that can spread and cause significant illness, and death, without treatment.

Myth #2: You Can Tell Whether a Mass Is Cancerous by Its Appearance

Many owners assume they—or our oncologists—can tell whether a mass is cancerous by the way it looks or feels. Although some tumors do have a characteristic appearance, such as a melanoma’s dark coloration, we can never be certain what cell types a mass contains, without diagnostic testing. After collecting cells with a fine needle aspirate or surgical biopsy, we can microscopically examine them to help determine whether the mass is cancerous, and its cancer type and stage.

Myth #3: Only Older Pets Develop Cancer

Older pets are more likely to develop cancer, because their cells have had more time to accumulate genetic abnormalities and mutations; however, young pets can also develop cancer. Cancers such as osteosarcoma and lymphoma are commonly diagnosed in dogs younger than 2 years of age. Others, including rhabdomyosarcoma, neuroblastoma, and nephroblastoma, originate from primitive tissue lines, and develop most commonly in young pets. Cancers that develop in young pets tend to be aggressive, so prompt diagnosis and treatment are critical.

Myth #4: A Cancer Diagnosis Means a Poor Prognosis for My Pet

Pets develop many different cancer types, each with its own characteristics. Although some cancers are aggressive, many types are slow growing, non-aggressive, and do not metastasize (i.e., spread). Single masses can often be completely removed surgically, and additional treatment options may be available for those that cannot be totally excised. Many cancer types can be cured, or put into remission, with treatment.

Myth #5: Chemotherapy Is The Only Cancer Treatment Available for Pets

Although most cancer treatment plans include some form of chemotherapy, there are many additional options for treating your pet’s cancer. At AVES, our oncologist will work with you to develop a treatment plan best suited to enhancing the pet’s quality of life. In addition to chemotherapy, treatment may include:

Surgical excision, or debulking
Radiation therapy
Immunotherapy
Novel therapeutics, such as tumor DNA sequencing and targeted therapy

Myth #6: Chemotherapy Will Cause Debilitating Side Effects in My Pet

Chemotherapy effects are vastly different in pets than people. We believe that cancer treatment should never be worse than the disease itself, and chances are, your pet never knew she was sick. Chemotherapy doses for people are often high enough to kill rapidly dividing body cells, causing side effects such as nausea, vomiting, diarrhea, extreme fatigue, and hair loss, whereas the lower doses given to pets do not typically cause problems. In the rare instances that pets do feel bad during treatment, their symptoms can typically be managed with medications, or by using another chemotherapy type. To learn more about what you can expect if your pet needs chemotherapy, check out our article here.

Myth #7: I Will Need to Treat My Pet Differently During Cancer Treatment

Our goal is for your pet to go about her life normally during cancer treatment, and for you to enjoy your time with her. Chances are your pet will not feel any differently, except a little more tired, and she will be able to play, go on walks, and cuddle as normal. You won’t need to treat your pet as though she is sick, although you may find yourself giving her more attention and love than usual, which she will undoubtedly lap up.

Myth #8: Natural Cancer Treatments Are Safer for My Pet than Traditional Treatments

Although specialized diets, supplements, and herbal treatments may help with your pet’s cancer treatment, current research is not sufficient to support treating cancer with these modalities alone. If you wish to supplement your pet’s treatment plan with natural therapies, first speak with our oncology team, as some herbs and supplements may interact unfavorably with chemotherapy drugs or other treatments, and put your pet in danger.

Myth #9: My Pet Is Too Old for Cancer Treatment

We believe that age is only a number, and no pet should be discounted from treatment based on age. Since cancer is seen most frequently in older pets, many treatments are developed with this in mind, and your older pet can likely receive most cancer treatments, if she is otherwise healthy. Regardless of age, if your pet’s health concerns make certain treatments less suitable, our oncology team can likely still devise a treatment protocol for her from the many options available. If surgery is not a good option because of heart or kidney disease, for example, we will focus your pet’s treatment on other modalities, such as chemotherapy or immunotherapy.

Myth #10: Nothing I Do Will Prevent Cancer Development in My Pet

While this is true regarding many cancers, you can take measures to prevent some cancer types. For example, mammary cancer in pets is notoriously aggressive, but you can significantly reduce its risk by spaying your female dog or cat at an early age. Testosterone exposure also increases cancer risk, and neutering males reduces the chance of testicular and prostate cancers. Squamous cell carcinomas tend to develop on the skin of white or light-colored dogs and cats who have frequent sun exposure, so investigate sun protection options if your pet is at risk.

If you have fallen victim to one of these cancer misconceptions, you are not alone. Contact us if you still have questions about pets and cancer, or to discuss treatment options, if your family veterinarian has diagnosed cancer in your pet.