Impact of baseline versus intercurrent steroids administration on upfront chemo- immunotherapy for advanced non-small cell lung cancer (NSCLC)

Background: The baseline use of steroids has been associated with worse survival outcomes in patients with metastatic non-small cell lung cancer (NSCLC) treated with single-agent immune-checkpoint inhibitors. Objective: We investigated the impact of baseline versus intercurrent corticosteroid therapy on the efficacy of chemotherapy plus pembrolizumab (CT-ICI) as first-line treatment for advanced NSCLC patients. Methods: We conducted a retrospective study on metastatic NSCLC patients treated with upfront CT-ICI at our institution between March 2020 and December 2021. The use of steroids was considered as the administration of at least 10 mg of prednisone equivalent. Results: : Of 101 patients, 36 (35.6%) received steroid therapy at baseline, and 18 (17.8%) started steroids on treatment. Overall, median progression-free survival (mPFS) was 6.5 months (95% CI, 5.9-8.9) and median overall survival (mOS) was 18.2 months (95% CI, 8.9-NR). Patients taking baseline steroids had significantly shorter survival than those not taking them (mPFS 5.0 vs. 8.9 months, p=0.00011; mOS 7.0 months vs. not reached, p <0.0001). Intercurrent steroid administration was associated to prolonged OS (not reached vs. 8.9 months, p = 0.0057) but not PFS (6.1 vs. 9.2 months, p = 0.098). Baseline steroids were significantly associated with poorer survival outcomes in the multivariate model. Conversely, intercurrent prescription did not reach a significant value regardless of other pivotal variables included in the model. Conclusions: : Baseline steroid administration was associated with a detrimental effect on survival outcomes in NSCLC patients treated with CT-ICI. The role of intercurrent steroid administration should be further explored in larger studies.