How Do Doctors Decide Which Chemotherapy Drugs To Give?

The decision about what type of treatment to recommend to a patient is based on a number of factors. Factors related to the patient as well as what is known about the treatment being prescribed. Some of these factors are:

• Research: Chemotherapy was first introduced in the 1940's. For the next 20 years, it was considered an investigational treatment. In the last 50 years, chemotherapy information evolved and many more effective drugs have been developed. During all of this time, doctors have documented responses and conducted clinical trials comparing standard treatments to new treatments. This process of gathering information about drug treatment of cancer has helped to establish specific protocols (types of drugs, doses of drugs and schedule of drugs) based on the type of cancer, stage of cancer, and other specifics about a person's cancer. Currently, most types of cancer have some standard protocols that help guide the doctors in selecting the right treatment protocol for an individual with cancer.
• Response rates: In evaluating information and choosing a protocol for a given patient, doctors will consider the response rate of the particular type and stage of cancer to the proposed drug or drugs. Response rates refer to the number of people whose tumors will respond (shrink or disappear) to the drug or drugs given. Response rates are established through research. For example, a certain type and stage of cancer might have a 70% response rate to a certain combination of drugs. This means that 70% of the people with this type and stage of tumor have a response (shrinkage or disappearance of the tumor) to this combination of drugs. It also means that 30% of the people with this type and stage of cancer will not respond to the treatment or will have only a minimal response. Responses to therapy can be either complete or partial (these are defined according to the type of cancer and the specific protocol). Another consideration in determining which drugs to give is response duration. In other words, how long do the responses last? Through research, an average response duration for any given drug protocol has been documented. Doctors choose protocols with the highest response rates and longest known durations.
• The Health of the Patient:  Chemotherapy has toxicities.  It must be given with care - even to healthy individuals.  People who are extremely old and frail or who have other medical complications may not be able to tolerate certain chemotherapy protocols.  In these cases, the potential risks versus benefits must be discussed before deciding on the treatment.  In some cases, the doctors may suggest a single drug rather than a "standard combination" of drugs.  In other cases, the doctor and patient may decide not to pursue chemotherapy and, instead, focus on quality of life.

There is no one correct choice in choosing chemotherapy. Each treatment protocol has advantages and disadvantages, and there may be more than one good option. In addition, treatment choices can change over time. A good chemotherapy treatment choice at one time may not be the best choice at a later time.

Finally, although doctors use the latest research about cancer treatments and the best response rates to select the best treatment protocols for their patients, there is no guarantee that an individual will achieve the desired response. It is impossible to predict exactly the outcome of therapy for any individual. However, response rates have improved dramatically and new drugs are being developed continuously so outcomes will continue to improve.

More Chemotherapy Information:

Chemotherapy Terms Chemotherapy Protocols - How Chemotherapy Works How Chemotherapy Is Given How Doctors Decide Which Chemotherapy Drugs To Give How Long Chemotherapy Is Given How To Tell If Chemotherapy Is Working Cancer Cells & Chemotherapy Types of Chemotherapy Targeted Therapy The Immune System About Immunotherapy Hormone Therapy Chemoporotective Agents Chemotherapy Resistance Short & Long Term Side Effects of Chemotherapy Nadir Cancer Clinical Trials