Cat Chemotherapy: What It Is and How To Prepare Your Cat
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If your cat has been diagnosed with cancer recently, you might be thinking about chemotherapy as part of their treatment plan. This is a scary time for pet parents, and it’s important to be informed.
Learn about cat chemotherapy, the risks and benefits, and how you can prepare if your cat needs this cancer treatment.
Key Takeaways
- Chemotherapy may be recommended as part of a cat’s treatment plan for several reasons.
- Chemotherapy in cats comes in two main forms: IV infusions and oral medications.
- Chemotherapy aims to give your pet a good quality of life for as long as possible. These treatments can improve how your cat feels and can extend their life during cancer treatment.
What Is Cat Chemotherapy?
Because pets continue to live longer and have better access to veterinary care, cancer in cats is being diagnosed more often. In some cases, chemotherapy is a recommended part of the treatment plan, along with surgery, radiation therapy, and other cancer treatments.
Chemotherapy for cats is the use of medications to kill cancer cells. In cats, the goal of chemotherapy is not just to prolong life but also to maintain a good quality of life.
Chemotherapeutic agents target cells that multiply quickly, effectively killing cancer cells. Unfortunately, this sometimes results in damage to other rapidly dividing cells in the body, especially within the gastrointestinal tract or bone marrow.
While it might be expected for a person going through chemotherapy not to feel well, negative side effects in cats generally lead to a change in treatment.
Types of Cat Chemotherapy
While cancer is not as common in cats as it is in dogs, it’s a leading cause of death in both species.
Chemotherapy in cats comes in two main forms: IV infusions and oral medications.
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IV infusions: cyclophosphamide, doxorubicin, vincristine, carboplatin, mitoxantrone
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Oral medications: prednisolone, cyclophosphamide, toceranib
The specific drug your cat gets will depend on what type of cancer they have, the specific protocol (treatment plan) selected by you and your veterinarian, and your budget.
In some cases, a single-agent protocol is used, meaning only one drug is given. However, multi-agent protocols are more common.
Why Would a Cat Need Chemotherapy?
Chemotherapy may be recommended as part of a cat’s treatment plan for several reasons.
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Cancer has already spread (metastasized): Some cancers, like lymphoma, spread early in the disease course or before the cancer is diagnosed. Chemotherapy helps to kill microscopic cells and small tumors that have developed throughout the body.
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Cancer is likely to spread: Some cancers have a high likelihood of metastasizing, such as mammary cancer in cats. In these cases, chemotherapy may be recommended even if no evidence of spread is found, especially if the tumor is highly aggressive.
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The cancer can’t be removed surgically: Some cancers, such as gastrointestinal lymphoma, are not good options for surgical removal. In these cases, chemotherapy may be the main treatment recommended.
Lymphoma and mammary gland cancer are two common cancers in cats for which chemotherapy is often recommended. Other common cancers for which chemotherapy might be recommended include squamous cell carcinomas and soft tissue sarcomas.
Whether chemotherapy is part of the treatment protocol might depend on how aggressive the primary tumor is and whether it can be completely removed during surgery.
Risks of Cat Chemotherapy
Because chemotherapy targets rapidly dividing cells, the most common side effects in cats getting chemotherapy include bone marrow suppression and gastrointestinal (stomach) upset.
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Bone marrow suppression: Decreased white blood cell counts can lead to secondary infections. The lowest count usually occurs between five and 10 days after the medication is given, so blood counts are usually checked around one week after your cat receives chemotherapy.
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Gastrointestinal upset: Signs can include vomiting, decreased appetite, and diarrhea. These signs are mostly seen three to five days after treatment and last a few days.
Other less common complications include:
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Allergic reactions to drugs (facial swelling, anaphylaxis, vomiting)
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Extravasation injuries, which happen when the drug leaks out of the vein into the surrounding area, potentially causing tissue damage
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Liver or kidney damage
Alopecia in cats is not a common side effect of cancer treatment, but your cat might lose some whiskers or have a different texture to their fur.
Rarely, some chemotherapy agents can have long-lasting effects.
For example, this study found that doxorubicin can cause kidney injury in cats, which might put a cat into kidney failure. These sorts of effects are unlikely in cats given standard treatments, but underlying health conditions may contribute.
Cisplatin and 5-fluorouracil are two chemotherapeutics that should not be used in cats because of life-threatening side effects.
Cats tend to do well with chemotherapy. Because cats do not understand their cancer treatment, significant side effects are generally not tolerated in veterinary medicine. If a cat isn’t feeling well on a treatment protocol, your veterinarian will probably change the plan. The goal is to provide a good quality of life for your pet, not to extend their life regardless of the side effects.
Keep in mind that not all tumors will respond to chemotherapy. This means that your cat might undergo treatment and have no measurable change in tumor size or spread.
Benefits of Cat Chemotherapy
Chemotherapy aims to give your pet a good quality of life for as long as possible. These treatments can improve how your cat feels and can extend their life during cancer treatment.
Many factors affect life expectancy for a cat with cancer, regardless of whether they receive chemotherapy. Examples of these factors include:
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Type of tumor
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Aggressiveness of the tumor
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Whether the cancer has spread
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Other underlying health conditions
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How receptive the tumor is to chemotherapy
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The type of chemotherapy given
The benefits of chemotherapy have not been proven for every cancer type a cat could get, but they are well-established for some cancers, such as lymphoma. According to this study, around 75% of cats who get long-term, multi-agent chemotherapy will go into remission. Most pet parents who choose chemotherapy for their cat’s lymphoma feel that chemotherapy improves their cat’s quality of life, this study found.
Effectiveness of Cat Chemotherapy
Keeping in mind that the goal of chemotherapy for a cat isn’t necessarily to cure them at any cost, effectiveness is instead judged based on whether the cat goes into remission, how long they survive, and their quality of life while they undergo treatment. Most cats will not be cured of cancer with chemotherapy.
Cost of Cat Chemotherapy
The average cost of chemotherapy for a cat is $100 to $300 per dose. Cats may need three to six months of treatment, and overall costs can exceed $5,000.
Long-term chemotherapy treatments are usually given by a veterinary oncologist, which is a veterinarian who specializes in cancer treatment.
Pet insurance will often cover cancer treatment if cancer isn’t considered a pre-existing condition.
A comprehensive, or accident-and-illness, plan is your best bet for a plan that will cover cancer. Accident-only and wellness plans generally do not cover treatment for cancer. Something to keep in mind if you plan to rely on pet insurance is that you will usually need to pay the veterinarian for each visit up front and then submit a claim for reimbursement.
Chemotherapy is too costly for many pet parents, so please know that you are not alone if you are unable to afford this treatment for your cat. In these cases, it’s best to discuss other methods of ensuring your pet has a good quality of life for as long as possible, such as providing good pain control.
Your veterinarian might be able to make a treatment plan that fits into your budget. You can also consider fundraising or finding organizations that can help cover the cost of cancer treatment for your cat.
Preparation for Cat Chemotherapy
Your pet’s oncologist should give you instructions for how to prepare your cat for chemotherapy, and it’s very important that you follow their guidelines. Some medications will be given by an IV infusion in the hospital, but others will be given by mouth at home.
If your pet is coming to a clinic for treatment, the veterinarian might ask you to have your cat fast the day of their treatment. In some cases, the veterinarian might also recommend you give medications that can help decrease anxiety, such as gabapentin, before bringing them in.
In the clinic, your cat’s leg will be shaved and cleaned for the needle to be inserted into the vein. It’s common for the veterinarian to check your cat’s blood work before giving chemotherapy to check their white blood cell count and make sure they are okay to get their chemotherapy for the day.
Some clinics might have you stay with your cat during chemo for support, while others might have you wait elsewhere. This might depend on how your cat reacts to new environments, the structure of the hospital, and whether it is safe for you to be in the treatment area.
Care and Recovery From Cat Chemotherapy
After your cat gets chemotherapy, you’ll want to watch them for side effects, such as vomiting, diarrhea, and loss of appetite. Your cat might be tired the day of their treatment. Contact your veterinarian if you notice any side effects, especially if your cat isn’t feeling well overall. Your veterinarian might give anti-nausea medications or appetite stimulants, like mirtazapine.
Your veterinarian should also give you instructions for how to handle your cat safely after chemotherapy. Some chemotherapeutic agents should not get on your skin, and you’ll need to be cautious when cleaning up urine and feces.
Ensure other pets and children do not have access to the litter box, and be sure to use gloves when cleaning the box.
Alternatives to Cat Chemotherapy
Chemotherapy is one treatment option for cancer. In some cases, it is the main recommended treatment. In others, it is part of a multimodal treatment plan. Examples of other cancer treatments that might be recommended include surgery, radiation therapy, and immunotherapy.
Speak with your veterinarian to find out whether there is an alternative to chemotherapy in your cat’s individual case.
Cat Chemotherapy FAQs
Is it worth putting a cat through chemotherapy?
This is a very individual question. Most cat parents who choose chemotherapy report that they think it helped their cat keep a better quality of life and would choose it again. However, choosing not to do chemotherapy is also valid, so discuss all options with your veterinarian.
What is the success rate of chemotherapy in cats?
There is no overall success rate for chemotherapy in cats. Success depends on the type of cancer, how aggressive it is, whether it has spread, whether it responds to chemotherapy, and the specific protocol used.
Keep in mind that chemotherapy success for cats is based more on how long it extends your cat’s life, whether they go into remission, and their quality of life than it is on curing a cat of cancer.
How expensive is chemotherapy for a cat?
An individual dose of chemotherapy for a cat can run from $100 to $300 and total cost can reach or exceed $5,000.
The cost varies depending on the type of cancer, the protocol used, your cat’s size and overall health, and your geographic location.