*December 2020*

Identification of key oncogenic drivers and the development of targeted therapies with clinical activity in patients harboring actionable mutations have revolutionized the treatment paradigm in non–small cell lung cancer (NSCLC), redirecting attention toward advances in biomarker testing methodologies. This new focus is poised to foster granular refinement of precise, targeted treatment of lung tumors.

Advances in NSCLC research have enabled an understanding of the disease as a collection of molecular subgroups. The proliferation of alteration-matched therapies specific to these subgroups is a prime example of a precision medicine approach. In addition to oncogenic driver mutations, therapeutic response biomarkers have been identified, such as PD-L1 expression as a predictor of immunotherapy efficacy.

Underscoring the importance of biomarker-guided treatment approaches, guidelines for molecular testing in NSCLC include an extensive list of alterations, such as sensitizing EGFR mutations and ALK gene fusions.1,2 The list continues to expand beyond these established canonical markers, with the addition of variants such as MET exon 14 skipping mutations and tumor mutational burden. In fact, the FDA recently approved therapies specific for tumors with these molecular characteristics. Read more.