However, it must be pointed out that potential differences of OS according to ALK status may have been confounded by post-progression treatments usually prescribed at our tertiary cancer center – including chemotherapy rechallenge, regorafenib, anti-EGFR rechallenge, temozolomide in MGMT methylated tumors and molecular profiling for inclusion in phase I trials with targeted agents [32]–[34]. This evidence concerns the gene MGMT and cancer.