Precisionmedicine 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.

Old-line chemotherapy drugs of the kind Dr. Sequist first prescribed were brute-force, indiscriminate weapons that targeted all dividing cells within the body. In killing cancer cells, they also caused collateral damage to healthy dividing cells, including those in the gut and the scalp. That's why so many cancer patients struggled with nausea and lost their hair.

But as researchers have identified the genetic changes that turn healthy cells cancerous, that knowledge has led to targeted therapies — smart bombs aimed precisely at molecules found in cancer cells but not in healthy cells. Dr. Sequist has specialized in treating one such molecular target known as epidermal growth factor receptor (EGFR).