IV.

How Chemotherapy Is Administered

A cancer patient often receives two or more chemotherapy drugs at the same time. Such combination therapy provides a maximum assault on cancer cells, since each drug attacks different parts of the cell cycle. This approach enables physicians to prescribe lower dosages of each drug than would be needed if one drug was used alone, lessening the toxic side effects of chemotherapy. Combination therapy can also prevent cancer cells from developing resistance to chemotherapeutic agents, as might occur after prolonged exposure to a single drug.

Chemotherapy is also frequently combined with surgery and radiation to fight cancer. In some instances, chemotherapy can render cancer cells more prone to the effects of radiation. Chemotherapy can also enhance the effects of surgery, since the drugs can reach and destroy cancerous cells near the site of a surgically removed tumor. Ideally, the combination of surgery, radiation, and chemotherapy will attack and neutralize cancer while maintaining as much of the body’s healthy cells and tissue as possible.

Depending on the drug and the type of cancer, chemotherapy can be administered in pill form or by a needle injected into a muscle, under the skin, or into a vein (known as an intravenous injection). In the case of an intravenous injection, the drug may be injected into the body all at once or allowed to drip slowly into the body from a bag suspended above the patient.

To save a patient from repeated sticks of a needle each time an intravenous drug is given, doctors sometimes install vascular access devices. One such device consists of a flexible tube called a catheter. One end of the catheter is inserted under the skin and the other end is attached to a port, an opening through which medicine is inserted. The catheter permits not only the administration of drugs but also the drawing of blood. Ports can also be surgically inserted beneath the skin, often near the collarbone. Some patients use miniature pumps containing chemotherapy drugs. These pumps are small enough to fit unobtrusively in a pocket or on a belt, enabling patients to leave a treatment facility and go about their normal routines while the pump automatically feeds a steady dosage of drugs through a port.

Chemotherapy is usually administered in cycles, in which treatment periods alternate with periods when the body is given the chance to rest and recover. Chemotherapy schedules vary widely, depending on the patient’s illness. One patient may receive medication one day a month, another patient five times a week, and another in three-week intervals. An entire course of chemotherapy treatment can last from a matter of weeks to several months or longer.