In recent years, we have learned a tremendous amount about the basic biology of cancer. At the fundamental genetic level, for example, changes in the DNA sequence (mutations) actually drive cancer cells into uncontrolled growth.

If we can find ways to precisely target cancerous mutations, we can stop the cancer cells from growing and cause the tumor to shrink and even go away, while having less negative impact on normal cells in the process.

Securing a target

The challenge in precision medicine is to understand the genetic and biological makeup of individual tumors so that the correct targeted drug can be selected for each patient. Several laboratories across the U.S. and the U.K. recently led a study based on biopsies of the tumors of 150 men with advanced prostate cancer. Overall, approximately 90 percent of them had some kind of genetic anomaly that could possibly be treated with drugs or therapies that we already have, but previously hadn’t realized might be useful in treating this cancer.

"...cancers that were once virtually a death sentence are now, in some cases, diseases that can be managed successfully for a relatively long period of time."

This study found BRCA1 and BRCA2 mutations in some cases of prostate cancer. Since we already have drugs that target BRCA1/BRCA2 mutant cancers, we can now ask if a drug like olaparib, which is effective in BRCA-mutant breast cancer, can also work against BRCA-mutant prostate cancer. If so, we would have a valuable new tool against the disease that is second only to lung cancer as the primary cancer killer among men.

Changing expectations

More research is needed to find out how this approach can help men with prostate cancer, but the prospect of developing treatments aimed at specific anomalies is a very exciting one.

What does this mean for patients? It means that cancers that were once virtually a death sentence are now, in some cases, diseases that can be managed successfully for a relatively long period of time. Precision medicine will allow us to do a much better job selecting the best medicine for each patient, increasing the benefit and reducing unnecessary side effects.

If you are faced with a cancer diagnosis, be sure to ask your oncologist about targeted treatments, genomic analysis, and precision medicine. There may also be a clinical trial testing new treatments for your cancer. Be sure to discuss that possibility with your doctor and consider whether participating in a trial is right for you.