Chemotherapy, what for?
Chemotherapy is the therapeutic use of medicinal agents to destroy or inhibit the growth and division of cancer cells.
Chemotherapy attacks specific processes that occur inside the cell (such as DNA replication) or other cellular activities that are necessary for cell replication.
In which cases is chemotherapy used in dogs?
Chemotherapy can be used in different cases.
Adjuvant chemotherapy
Adjuvant chemotherapy is used following surgery when the surgeon has not been able to remove all of the tumor, when the tumors are extensive, or when there is a significant metastatic risk.
In dogs, tumors for which this approach is regularly used include osteosarcoma, hemangiosarcoma but also for cancers of the udder, thyroid, anal sac, bladder or tonsils.
Palliative chemotherapy
Chemotherapy can also be used to improve the animal's quality of life without expecting complete remission following treatment. Palliative chemotherapy is generally used in the management of inoperable tumours.
Neoadjuvant chemotherapy
Also called induction or inductive, neoadjuvant chemotherapy consists of administering a treatment before surgery.It is assumed that it will thus reduce the size and invasiveness of a primary tumor, which increases the rate of surgical cure.
How is chemotherapy given?
Chemotherapy can be administered in several ways, depending on the type of chemotherapy drug and the protocol used, which obviously depends on the type of cancer and the animal.
Traditional protocols are based on giving the best tolerated dose, followed by a break (from one to a few weeks, depending on the protocol) before the next dose. Depending on the drug, chemotherapy can be given as an injection or an oral tablet. The minimum duration of hospitalization is 24 hours after each administration of anticancer drug and all residues of cytotoxic drugs secreted by the animal (in its urine, faeces or possible vomiting during the days following each chemotherapy session must be handled and disposed of with special precautions.
For certain types of cancer, the veterinarian may use so-called metronomic protocols. They consist of the chronic administration, at regular intervals, of low-dose chemotherapy drugs, usually given daily or every other day.
What are the side effects of chemotherapy?
Chemotherapy specifically targets cells that multiply rapidly, which is the case for cancer cells but also for certain he althy cells such as those in the hair follicles, intestine or bone marrow.
By destroying these he althy cells, chemotherapy can cause side effects such as:
- hematological disorders: damage to bone marrow cells can reduce the amount of red blood cells in dogs and white blood cells. Consequently, the dog may then show signs of anemia and exhibit a drop in its immunity which makes it more susceptible to opportunistic germs.A transient and reversible decrease in white blood cell count can sometimes lead to fever, fatigue, or an inability to fight off a possible infection,
- digestive disorders such as decreased appetite, vomiting, diarrhea or constipation,
- hair loss or alopecia,
- heart trouble,
- kidney trouble,
- liver disorders,
- nervous disorders,
- blood clotting disorders,
- etc.
The side effects depend not only on the molecules used but also on the animal.
In order to limit the occurrence of these side effects, examinations are regularly performed on dogs undergoing chemotherapy to be sure that the protocol is well supported. Before each chemotherapy treatment, the veterinarian notably carries out blood tests to check the quantity and quality of your animal's blood cells.
It should be noted, however, that if all the necessary precautions are taken, the side effects of chemotherapy in dogs are in no way comparable to the side effects of chemotherapy in humans. These effects would only be observed in 25 to 30% of treated dogs and are most often of low intensity and transient.
Always keep in mind that your veterinarian will not offer you this kind of treatment if he feels that your dog will not tolerate it well or if he has a tumor known not to respond well current veterinary chemotherapy drugs.
Phytotherapy to the rescue
" Phytotherapy can support chemotherapy by helping the dog&39;s body to better support anti-cancer drug treatments, to limit the loss of muscle mass associated with cancer and to reduce pain. On the other hand, when an anti-cancer treatment is in progress, herbal remedies must imperatively be prescribed by a specialized veterinarian because of the many possible interactions with drugs.Be aware that there are also many alternative anti-cancer treatments from phytotherapy aimed at overcoming conventional chemotherapeutic treatments. Treatments based on Tahitian vanilla and Cinchona bark (DNA PKASE Inhibat) or based on mistletoe (VAF or Viscum Album Fermenté) exist and can be of great help. Speak to a specialist veterinarian."