Your Response to Treatment

When considering a new treatment, your doctor may describe to you how groups of women in a particular study have responded to it. For example, your doctor may say, "This chemotherapy has a response rate of 30%," meaning that 30% of the women who take this particular chemotherapy program will "respond." Response is defined as a 50% or greater reduction in the size of the tumor that lasts three months or longer.

Doctors may use several terms to describe response to treatment:

• A complete response is complete disappearance of cancer (also called complete remission).
• A partial response is a 50% or more reduction in the size of the tumor.
• A minimal response is less than 50% reduction.
• Stabilization means that the cancer remains the same.
• Progression means that the cancer is growing and enlarging.

Some treatments work faster than others. Treatments that are slower to act are not necessarily less effective in the long run. Whole-body treatments such as hormonal therapies may take a few months to provide you with a full response. And at least two cycles of chemotherapy are usually given before your doctor will repeat tests to evaluate the cancer's reaction.

The cancer's response to treatment should be checked regularly. Your response to a treatment is measured, in part, by lessening symptoms—pain relief, increased daily activity, easier breathing. It is also measured by comparing your blood and radiology tests before and after treatment. How you respond to a particular treatment helps you and your doctors determine the value of that therapy for you.

It usually takes several months after you begin a treatment to see how well you're doing.

A new test, CellSearch, can speed this process considerably. Before treatment starts and then a few weeks later, the test counts how many cancer cells are in a sample of your blood. The U.S. Food and Drug Administration approved this test in January 2004. But it is expensive and still isn't widely available. Ask your doctor if you are interested in getting more information about it.

If the cancer grows in spite of treatment, the cancer cells have probably developed resistance to whatever treatment you are receiving. More of the same medication would be unlikely to help you. In most cases your doctor will want to put you on a different drug that works in a different way, with a better chance of beating the cancer. For example, if you developed metastases while you were taking tamoxifen, then a different attack, using an aromatase inhibitor or chemotherapy, might work better.

Before you have any procedure or start any kind of treatment, you must be told about the possible benefits and side effects, and you must sign a consent form. You have the right to refuse a procedure or treatment. You also have the right to stop a treatment at any time, even after you have started.

Stick with a treatment that is working and has side effects that are acceptable to you. Stop what is not working and try something that your doctor thinks might do the job. But be careful about making rushed decisions and switching too fast. You have to give each treatment plan a fair chance before judging its ability to help you.