Chemotherapy is the use of a drug or combination of drugs to slow, shrink or rid the body of cancer cells. Since chemotherapy has a systemic effect, some side effects may be noted.
What Are Common Side Effects Of Chemotherapy?
Side effects of chemotherapy are highly dependent of the drug in use. Each protocol is different and monitoring is tailored to fit each individual situation. Most chemotherapy agents have a “BAG” – Bone marrow suppression, Alopecia (hair loss), and Gastrointestinal – of side effects. The reason these side effects are so common after chemotherapy administration is because these tissues contain cells that are rapidly growing and therefore inherently sensitive to chemotherapy. Therefore, cells such as those found in the bone marrow, as well as gastrointestinal epithelial cells and hair follicle cells that rapidly turnover are quite sensitive to chemotherapy, whereas cells that slowly turnover, or do not turnover (e.g., spinal cord, muscle, etc.) are generally extremely resistant to most chemotherapy agents.
Hair loss is a rare side effect of chemotherapy in dog and cats, though it can occur in any breed of dog.
Gastroenteritis (vomiting and diarrhea) is seen in 15% of dogs and cats receiving the majority of chemotherapy drugs, whereas nausea is thought to be seen in 50%. This side effect is generally seen 3 to 4 days after chemotherapy administration and lasts for 2 to 4 days. Gastroenteritis is the most common side effect noted with chemotherapeutics.
What Monitoring Is Recommended For My Pet?
A pre-treatment complete blood count is required within 24 hours before EVERY chemotherapy administration that causes bone marrow suppression.
What Are The Treatments For Side Effects?
Medications that reduce the risk of vomiting and diarrhea are often used in patients receiving chemotherapy. These medications are often administered proactively and on an as-needed basis.
What Are Other Cancer Treatments?
Surgery and radiation therapy are the other legs of cancer treatment in pets. Radiation therapy is typically conducted at universities or large referral centers.
Monoclonal antibody therapy is a promising treatment modality that is on the rise in veterinary medicine. Currently, in human medicine, monoclonal antibodies are used as an adjunctive treatment for cancer patients.