Afatinib in the treatment of squamous non-small cell lung cancer: a new frontier or an old mistake?

Lung squamous cell carcinoma represents approximately 20% of all non-small cell lung cancer (NSCLC) and is associated with a very poor prognosis. In the randomized phase III LUX-Lung 8 trial afatinib showed a statistical significant efficacy advantage compared to erlotinib as second-line treatment of advanced/metastatic squamous NSCLC. Despite its well-built design and the statistical significant results, in our opinion the study is still far from being clinically relevant for this subset of patients. Moreover, during the last years other drugs have shown encouraging activity with low toxicity in pretreated lung squamous cell carcinomas. In particular, nivolumab in the treatment of platinum-pretreated squamous NSCLC has recently radically changed the treatment paradigms in this histology. Sure, LUX-Lung 8 trial achieved its primary endpoint progression-free survival showing some afatinib activity in one of the most difficult-to treat and genetically complex neoplasm but we haven't found the most active drug in this subset of patients yet. The purpose of this editorial is to discuss some of the most controversial aspects of the LUX-Lung 8 trial focusing especially on its rational and design.