More than one-third of advanced non-small-cell lung cancer patients do not receive immunochemotherapy due to intolerance.

BACKGROUND: Combination therapy with immune checkpoint inhibitors (ICIs) and chemotherapy (ICI + chemotherapy) has become the standard first line treatment for driver oncogene-negative advanced non-small-cell lung cancer (NSCLC). However, it may be more toxic compared to monotherapy, which limits its use. Moreover, the feasibility of the combination therapy in clinical practice remains unknown. METHODS: We conducted a cohort study to determine the implementation rate of ICI + chemotherapy in clinical practice. We retrospectively reviewed clinical data from advanced NSCLC patients who received systemic therapy at 13 institutions between December 2018 and December 2020. RESULTS: After excluding 154 patients with epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) gene alterations, a total of 919 NSCLC patients were included. Among them, 442 were treated with ICI + chemotherapy (48%), whereas 477 were treated with other therapies (52%). Among these 477 patients, 340 did not receive ICI + chemotherapy because of intolerance (71%); thus, more than one-third of the advanced NSCLC patients do not benefit from the combination therapy due to intolerance. Among the 659 NSCLC patients for whom PD-L1 was < 50% or unknown, only 342 received the ICI + chemotherapy combination (52%) even though it is considered preferable to either therapy alone; the remaining 318 patients were treated with other therapies (48%). Among the 318 patients who did not receive ICI + chemotherapy, 274 were intolerant to it (86%). CONCLUSION: Our results revealed that a substantial proportion of advanced NSCLC patients did not benefit from ICI + chemotherapy due to intolerance. As treatments for NSCLC are moving toward combinations for greater efficacy, their feasibility in clinical practice must be taken into consideration.