Chemotherapy

The term "chemotherapy" refers to any type of therapy that uses chemicals to kill or halt the growth of cancer cells. The drugs work in a variety of ways, but are all based on the same simple principle: stop the cells from dividing and you stop the growth and spread of the tumor.

Until recently, chemotherapy was used only to relieve symptoms associated with very advanced or metastatic disease. With the publication of two studies in 2004 showing that the use of docetaxel (Taxotere) can prolong the lives of men with prostate cancer that no longer responds to hormone therapy, more and more doctors are recognizing the potential benefits of chemotherapy for the men they treat with advanced prostate cancer.

Building on these successes, there are now dozens of clinical trials studying various combinations of chemotherapy drugs, some using new mixes of older drugs and some using newer drugs. Some trials are looking to find a chemotherapy regimen that’s more tolerable or more effective than docetaxel in men with metastatic disease, others are looking to find a chemotherapy regimen that can delay the onset of metastases, and still others are seeking to improve upon the results with docetaxel by adding to it other novel agents and testing the combination.

Paramount in all researchers’ minds is a way to maximize benefit while minimizing side effects. Chemotherapy, like all powerful drugs, can take a toll on the body. A review of how to best manage the side effects of chemotherapy can be found in the Side Effects section.

Off-Label Chemotherapy Use

Strictly speaking, few chemotherapy agents have been approved by the FDA for use in prostate cancer. But over the years, doctors have found that some medications that are regularly used in other types of cancers can be used rather effectively in men with prostate cancer.

Off label use of a drug means that the drug is approved by the FDA for use in one disease but is being used in another. The drug is known to be safe overall, and has been proven effective for the disease in which it’s approved. That doesn’t mean it’s not effective in prostate cancer as well; it just means that the drug hasn’t been rigorously tested in prostate cancer, so there’s no formal "proof" that it’s effective. Nevertheless, off-label use of chemotherapy is common, and its use is often found to be beneficial in men with prostate cancer.

Because very few drugs will score a home run in every person, second-line chemotherapy has a long and valued tradition in the treatment of cancer. In this setting, off-label drugs are common, and are chosen specifically because they work somewhat differently than what was used first, providing another chance to see a benefit.

Additional Reading:

Side Effects of Chemotherapy

Chapter 7: The Role of Chemotherapy

Prostate Cancer News: Treatment and Outcomes