Personalized medicine offers huge promise

By Dr. Burton L. Eisenberg

Categories: Cancer


In the State of the Union address, President Obama emphasized the importance of medical treatments tailored to genetic and other characteristics of individual patients, otherwise known as personalized medicine.


Ever since molecular biologists Francis Watson and James D. Crick introduced the world to the double helix in 1953, scientists have predicted an era of personalized medicine in which each patient's DNA would factor into treatment decisions.


We are now living in the early years of that genomic era. Science is continuously making strides — from the discovery of biomarkers that can predict how well a person will respond to a specific drug, to gene-based risk assessments for a variety of ailments.


And now researchers and clinicians are expanding the definition of genomic medicine to include not only the genetic makeup of a patient, but the genes that make up his disease.


In the fight against cancer, World Cancer Day is a unique opportunity to raise awareness in the areas of prevention, early detection, treatment and care. Examining the DNA of cancer, we now realize that two patients withcolon cancer actually have two very different diseases.


The genes that contribute to the development and progression of cancer can be individually distinct. This is incredibly exciting. Instead of treating "colon cancer patients," we are entering an age in which we will recommend therapeutic options for cancer patients based on their unique and individual illnesses.


At Hoag, we are developing an affiliation with the Keck Medicine of USC to leverage the university's impressive technology and give Orange County patients local access to some of the most cutting-edge genomic medicine research in the world.


That doesn't mean we're going to eradicate cancer in Orange County in a couple of years. Too many scientists made the mistake of promising an end to disease more than a decade ago, when the first human genome was sequenced. That didn't happen because, as it turns out, understanding the human genome was just the beginning.


We now know that it's not just about mapping genes, but understanding gene expression, or what happens when a gene goes awry. So too do we need to understand that sequencing the genes of disease will at first yield limited results. But the promise is significant.


Already our understanding of the cancer genome is changing the way we approach certain diseases. Up until three years ago, melanoma was treated almost exclusively (and not very successfully) with chemotherapy.


We now know that 50% of melanomas have a genetic mutation that helps cancer cells grow, and oncologists are able to shrink these previously untreatable tumors, albeit for a limited time, with drugs targeting that specific genetic mutation.


No, we haven't yet cured cancer. But every day, our deepening understanding brings us closer to a world where we can anticipate control over previously incurable malignancies.


Dr. BURTON L. EISENBERG is the executive medical director for the Hoag Family Cancer Institute and the Grace E. Hoag executive medical director endowed chair.