Health

14 HEALTH • September 21, 2015 Genome sequencing, targeted therapies improve recovery odds \\ By Livia Gershon W hen people find out what Dr. Mark Brenner, the chief radiation oncologist at Saint Vincent Hospital in Worcester, does for a living, he says he often gets one response in particular. "People are always saying 'Oh my God, you must have the most depressing job in the world because you work with cancer.' " Not even close, Brenner says. A lot of diseases—diabetes, congestive heart failure, hypothyroid- ism, and other ailments—can be controlled but seem to be far from a cure. With cancer, a steady stream of new developments means that, with more and more patients, it's entirely reasonable to talk about curing their disease. TACKLING CANCER, ONE PATIENT AT A TIME Over the last few years, these new discover- ies have changed the face of cancer treatment. In many situations, it's now possible to choose a course of action not just based on the type of cancer and how far it's progressed but also the specific genetic sequences found in a tumor sample. "Every area of cancer medicine has gone through light years of change in very recent times," Brenner said. Brenner compares the new diagnostic tools with the standard approach to a respiratory tract infection. A doctor can take a swab from a patient, send it to a lab for culture, and determine not just that the infection is bacte- rial but the precise antibiotic that will do the best job fighting it. "It's much more individualized treatment," he said. "It's much more personal." The advantage is not just that cancer treat- ments chosen using genomic testing are more precisely tuned to a particular patient's disease but that it avoids overtreatment. If a treatment that stimulates an immune response is very likely to be sufficient, there may be no need to use aggressive methods like chemotherapy. "You don't want to take an elephant gun when a fly swatter will suffice, and neither do you want to take the fly swatter when you need the elephant gun," Brenner said. Personalized therapy not so novel? Dr. Alan Rosmarin, chief of hematology/ oncology at UMass Memorial Medical Center in Worcester, said that, depending on how you define it, personalized cancer care has been happening for decades. Even years back, doc- tors looked for estrogen or progesterone receptors on breast cancer patients' tumors to determine whether the cancer was likely to respond to hormonal treatments. The difference today is the range of tools that are available and the variety of ways they can be applied, said Rosmarin, who is a mem- ber of the American Cancer Society's New England Division board of directors. Instead of just looking at one or two characteristics of a tumor, doctors may sometimes sequence hundreds of genes to find out more about how it operates. The jump forward is due largely to the international human genome project funded by the U.S. government, which was completed in 2003 and produced findings that medical science continues to build on. "We now have a complete atlas, if you will, of all conventional genes and proteins," Rosmarin said. Add to that the falling cost of sequencing DNA and it's now possible to gather huge amounts of data not just for research purposes but to determine a course of treatment for an individual patient. Rosmarin said how much testing is done in any particular case depends on the patient's situation and also the type of hospital they ILLUSTRATION/DREAMSTIME.COM

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