*January 2019* Harvard Health Publishing, Harvard Medical School, by Stephen Lyons. When Dr. Lecia Sequist was undergoing her training to become a medical oncologist at Massachusetts General Hospital (MGH) in the early 2000s, the treatments available for lung cancer were very limited. Radiation and surgery were seldom options, because in most patients the cancer had already spread beyond the lungs by the time they were diagnosed. That left an array of chemotherapy drugs, all with unpleasant side effects. None had long-lasting benefits. Average life expectancy was only a year.

“It was a sad time, because a diagnosis of lung cancer was a pretty grim outlook,” says Dr. Sequist, now the Landry Family Associate Professor of Medicine at Harvard Medical School.

Over the last two decades, however, scientific discoveries and new approaches have dramatically improved outcomes, greatly increasing life expectancy for some patients.

“Every day in clinic, and every time we meet a new patient, we see that these advances are making a difference,” says Dr. Sequist. “It’s really been a remarkable thing to watch unfold and to be a part of.” Read more.

Precision medicine transforms lung cancer treatment

This transformation illustrates a broader change going on in health care today: the emergence of precision medicine. Historically, most medical treatments have been designed to treat the average patient. Because all people are different, this one-size-fits-all approach has resulted in treatments that work well for some patients, not so well for others. But over the last 15 years, since the sequencing of the human genome, doctors in many fields have developed treatments more tailored to individual patients, taking into account not only their unique genetic makeup, but also factors like lifestyle and environment. Cancer treatment is one of the areas in which precision medicine has borne the most fruit.

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