Chemotherapy in Small Animals

Chemotherapeutic drugs (anticancer drugs) are used in the treatment of several types of cancer in pets. The type of cancer and extent of disease help us decide what protocol (type of drugs, dose, and schedule) to use for treatment.

I. When do we use chemotherapy to treat animals with cancer?

II. Will there be side effects from the drugs?

III. How are the drugs given? How often and how long does treatment last?

This varies, depending upon what type of cancer we are treating and which drugs we are using.

Some of the drugs are oral medication (pills) that you give at home, while others are injections or slow intravenous infusions that may require 1-2 days in the hospital.

The treatments are usually repeated weekly, every other week or every third week.

It is most important that you, as an owner, are committed to treatment and bring your pet in when scheduled for therapy.

The duration of the chemotherapy depends on the type of cancer and stage.

Some animals need to receive chemotherapy for the rest of their lives, but in others, treatment may be discontinued for a period (weeks to months) if the tumor is in remission (i.e., not evidence of disease or NED). Chemotherapy is resumed when there is a tumor relapse.

We usually recommend that every patient receive at least 2 cycles of chemotherapy and then be evaluated for response before we decide to continue the treatment, change the drugs, or discontinue chemotherapy.

IV. What can you expect from chemotherapy?

In many cases, we are not able to cure our patients with cancer. We are often talking about palliation, i.e., prolonging your pet's life and slowing down the progression of the disease.

From what we know about the type of cancer your pet has, we may be able to give you a prognosis about life expectancy with chemotherapy.

We want to give your pet a long life while striving for a good quality of life.