Continuation of afatinib (A) beyond progression: results of a randomized, open-label, phase III trial of A plus paclitaxel (P) versus investigator's choice chemotherapy (CT) in patients (pts) with metastatic non-small-cell lung cancer (NSCLC) progressed on erlotinib/gefitinib (E/G) and A: LUX-Lung 5 (LL5)