Antineoplastic Agents

Antineoplastics are Chemotheraputic Agents. The choice of which antineoplastic to use depends on what the cell type of the tumor is, and on its site of growth.

Because antineoplastic agents are cytotoxic (poisonous to cells) they not only interfere with the growth of tumor cells, but those of normal cells. Antineoplastic agents have more of an effect on the tumor cells than normal cells because of their rapid growth. Those normal tissue cells that are the most effected are bone marrow (seen in low blood counts), hair follicles (seen by way of hair loss) and the GI mucosal epithelium (accounting for nausea, vomiting in humans, loss of appetite, and diarrhea).
It is a very narrow margin deciding the right dose to use for destroying the tumor cells in order to have the lease affect on normal healthy cells.

Endocrine antineoplastic chemotherapy such as Tamoxifen is what is considered additive or ablative therapy. It is not a cure but provides palliative therapy, where hormone dependent malignant tumors expressing estrogen receptors have been present, as effectively as does an oopherectomy/ovariectomy (removal of ovaries). It is most effective when used to prolong disease free survival in breast cancer therapies in humans.

It is important to be alert to signs that may accompany the use of antineoplastics such as: increased fluid retention leading to CHF, as well as, increased susceptibility to infections due to immunosuppression. Additional medications may need to be given to help resolve CHF. Good handwashing techniques before and after giving care will help to reduce possible introduction of infection.

It is recommended that care be given to prevent undue cytotoxic exposure by wearing disposable nonpermeable gloves when handling the medication, and when cleaning the animal or its habitat.