Outcome of patients with lung adenocarcinoma with transformation to small-cell lung cancer following tyrosine kinase inhibitors treatment: A systematic review and pooled analysis

Lung adenocarcinoma can transform to small-cell lung cancer (SCLC) when resistance to tyrosine kinase inhibitors (TKIs) develops. This phenomenon has repeatedly been described in several case reports and small patient series. The characteristics and treatment outcomes of this population, however, have not been comprehensively reported.