FACT: Personalized medicine has already changed the lives of hundreds of thousands of people, and is well on its way to changing the lives of millions.

FACT: Depending on the results of a genetic test, certain medicines can be prescribed that can extend the life of a cancer patient by months or even years.

FACT: Today, the cost to sequence an entire human genome is $5,000. Within the next two years, the expected cost is $1,000, about the price of an MRI.

Personalized medicine refers to the tailoring of medical care to the individual characteristics of each patient, often by classifying individuals into subpopulations based on their genetic makeup. Preventative or therapeutic interventions can then be concentrated on those who will benefit, sparing expense and side effects for those who will not.

Two examples of recently approved, life-extending, personalized medicines (also referred to as targeted therapeutics) are Xalkori (from Pfizer) for nonsmall cell lung cancer and Zelboraf (from Genentech and Daiichi-Sankyo) for metastatic melanoma.

To receive either drug, a genetic test must be conducted on the relevant tumor tissue. In both cases, if the patient’s tissue does not have a particular mutation, neither drug appears to be effective, and if the individual still chooses to try the treatments, insurance companies are not likely to reimburse them for the drugs.

To date, the majority of personalized-medicine treatments are in oncology, but there are emerging examples in cardiology, particularly for the millions of patients who have received stents and are currently taking Plavix. Based on recently published research, Plavix does not appear to work for a small percentage of patients with a certain genetic makeup, while an additional group of patients might need their Plavix dose dramatically increased for the drug to work effectively.

Although I am not a physician, I would recommend that all cancer patients bring up the subject of genetic testing and personalized medicine. For instance, if I had melanoma or nonsmall cell lung cancer, I would want to know if I were a candidate for these new cancer therapeutics. Or if I were taking Plavix after receiving a stent, I would want to know whether the Plavix was working and whether I was taking the right dose.

Have you or would you feel comfortable raising the subject of personalized medicine or genetic sequencing with your doctor?

When the price to sequence my genome drops to $1,000, will I do it? I think so. That said, assuming I am still healthy, I would want to think through the privacy issues as well as who would pay the bill. And you should think about these issues as well.

Editor’s note: For more information on personalized medicine, visit www.personalizedmedicinecoalition.org or http://health.usnews.com/health-conditions/cancer/personalized-medicine.