Just a few years ago, the only distinction in the field of lung cancer that meant anything was small cell vs. non-small cell. The different types of non-small cell, like adenocarcinoma vs. squamous cell vs. large cell, were of little interest and didn’t change management (only a very recent development). And although we often asked about smoking history, the answer never changed our treatment plan. Only in the last few years have we come to recognize that we will do better as “splitters” than as “lumpers”, by tailoring our treatment recommendations to the clinical and molecular feature of one particular patient and tumor at a time, rather than using a one size fits all approach.

First, some definitions. Although there is a little variation, most of the lung cancer research community has come around to a definition of a “never-smoker” as less than 100 cigarettes in a lifetime. A “former smoker” is more than that and has quit smoking for at least a year. A “current smoker” is anyone else, so less than a year after quitting, a patient is still considered a current smoker. Continue reading →