On Wednesday, America received the sad news that former President Jimmy Carter has cancer that has spread to other parts of his body, or metastasized.
Over the past 90 years of his lifetime, our understanding of cancer and options for cancer therapies have made incredible advances.
In 1924, the year Carter was born, physicians had only a vague notion of what cancer really was, had no idea what caused cancer, and no genuinely effective treatments other than surgery, which worked only for localized disease. Scientists were experimenting with radiation, but often with disastrous side effects due to doses that were far too high. It was not until Jimmy Carter was 10 years old that radiation was first used successfully to treat cancer.
Progress in using drugs to treat cancer, or chemotherapy, was even slower. Despite some promising early studies in the 1940s, and extensive hard work in the 1950s, it was not until the mid-1960s, when Carter was serving in the Georgia State Senate, that the first successful chemotherapy regimen was developed for pediatric leukemia.
During this period, fundamental advances in our understanding of biology, DNA, and genetics were taking place, and connections were being made between DNA and cancer. The first chromosomal change associated with cancer, the Philadelphia chromosome, was discovered in 1959, while the first oncogenes were discovered in 1970, when Carter was running for governor of Georgia.
During Carter’s term as President, a revolution in molecular biology and recombinant DNA technology was fueling rapid advances in cancer research that have continued to accelerate to this day. Our understanding of hereditary factors in cancer susceptibility advanced in the 1990s with the identification of genetic mutations that predispose people to breast, ovarian and colon cancer. Several of President Carter’s family members have died from pancreatic cancer, illustrating how important genetic factors can be in cancer development.
The completion of the sequencing of the human genome at the turn of the millennium coincided closely with FDA approval of the first targeted therapy for cancer in 2001. This drug, known as Gleevec, targets the oncogene that is produced by the Philadelphia chromosome that was identified 42 years earlier, and is the signature mutation associated with chronic myeloid leukemia. Since the introduction of Gleevec, the five-year survival rates for CML patients have nearly doubled.
Over the past decade, there has been another revolution in biomedical research in DNA sequencing. The reduction in costs of genome sequencing has made it possible to sequence the tumors of thousands of cancer patients. All this new data has identified many new possible drug targets, as well as potential biomarkers that may better detect cancers early before they can spread. These rapid advances that allow doctors and scientists to characterize the molecular basis of an individual patient’s tumor is what underlies the recent Precision Medicine Initiative that was unveiled earlier this year by President Obama.
The options that are available today for cancer patients, such as President Carter, are far more effective than only a few years ago, often with fewer side effects. While treating cancers that have spread is still a major challenge, it is an area of intense research around the world.
I am thankful that President Carter has lived long enough to be able to potentially benefit from precision medicine, and hope that he is with us much longer. I am certain the dedicated team of physicians, scientists and nurses at the Winship Cancer Institute at Emory University will do their utmost to help achieve just that.
President Carter and his physicians will be announcing their treatment plans sometime next week after test results provide them with a better understanding of his current health.
Read CNNOpinion’s Flipboard magazine.