“It is more important to know what sort of person has a disease than to know what sort of disease a person has.” Hippocrates
When a patient receives the diagnosis of cancer, there isn’t just one treatment for every patient with that diagnosis. Just like shoes, one size does not fit all. Now, there are treatments that take into consideration the genetic makeup of a tumor and identify the best treatment that is customized for the specific tumor a patient has. This article will discuss personalized medicine that makes use of a targeted approach for the patient’s tumor.
How does precision medicine work?
For precision medicine to work on cancer, it requires two essential criteria to be met. Your doctor will take your tumor either from surgery or from a biopsy and determine the genetic makeup of the tumor. The genetic makeup of a tumor varies from one patient with a tumor to another patient with a similar diagnosis of cancer. Then, the tumor will be checked so that the treatment matches the genetic makeup of the cancer.
Some of the areas where personalized or targeted medicine may work include the following:
Now, it is possible using genomic testing to determine if a man’s elevated PSA requires a prostate biopsy. The 4K score is a blood test to help with the decision whether a biopsy is needed after a PSA test. The PHI (prostate health index) is used to help determine who is at high-risk for developing an active form of the disease that may spread beyond the prostate gland. With these tests, a urologist can tell the difference between prostate cancer that will never threaten a man’s health or well-being and one that is a “ticking time bomb.” The doctor can now determine, using personalized medicine, if the cancer is aggressive and requires immediate treatment or if it is very slow-growing as some prostate cancers can be, then the man is a candidate for surveillance.
Among the first targeted therapies developed was for those patients with acute lymphoblastic leukemia who carry the Philadelphia chromosome.
There are now two drugs, Kalydeco and Orkambi, which work by affecting a defective protein created in certain patients with cystic fibrosis. When there is a match, this young patient has a significant improvement in their lung function.
For patients with a type of breast cancer involving higher levels of the “HER2” protein, the drug Herceptin can be effective.
With advanced colon cancer, a type of targeted drug treatment called “monoclonal antibody therapy” uses the drugs Avastin or cetuximab to stop tumors from growing and spreading.
Paying for Personalized Medicine
Many of the treatments using personalized medicine are very expensive, some as much as thousands of dollars a month. That’s the bad news. The good news is that many insurance companies are picking up the tab leaving the patient with a reasonable out-of-pocket expense. The take home message: cancer is not cheap!
Bottom Line: Personalized medicine is focused therapy like a laser instead of using a shotgun treatment that may not be effective and is often associated with uncomfortable and debilitating side effects.
Dr. Neil Baum is a Professor of Clinical Urology at Tulane Medical School.