EGFR and non-small cell lung carcinoma: The American Society of Clinical Oncology (ASCO) guidelines recommend combination therapy of doublet chemotherapy (platinum/pemetrexed with maintenance pemetrexed) with gefitinib for patients with EGFR-mutant stage IV NSCLC (ECOG PS 0-2) who had not received systemic treatment and under conditions where there is an unavailability of osimertinib [59].