Before the discovery of predictive molecular tests (eg, EGFR mutation and ALK rearrangement), each chemotherapy drug for stage IV non–small cell lung cancer had about the same chance of success. Progress was made as more drugs were discovered. Patients lived longer with second- and third-line therapies, and studies were launched to improve the sequence and timing of drug selection.

The studies considered in this guideline update showed that second-line drugs given immediately after completion of first-line therapy (so-called “switch maintenance” therapy) improve survival. The studies that showed an improvement in overall survival did not mandate second-line therapy, and stopped therapy at four cycles in patients responding to first-line therapy. This leaves doubt as to how much survival gain was due to better treatment with switch maintenance, or undertreatment in the control arm.

Also, these studies were launched before the advent of molecular tests, which have since revolutionized chemotherapy drug selection for this disease. Still, these studies demand attention because they contribute to a march of progress in which more drugs, more choice, and more opportunities for treatment are leading to better outcomes for our patients. ■

Disclosure: Dr. Azzoli reported receiving research funding from Genentech, sanofi-aventis, and Eli Lilly.