Introduction

Pembrolizumab plus carboplatin and paclitaxel or nab-paclitaxel is established first-line therapy for metastatic squamous non-small cell lung cancer and improved survival in KEYNOTE-407 [1]. Immune checkpoint inhibitors cause a distinct spectrum of immune-related adverse events, and hepatic toxicity is reported in approximately 1%–6% of patients receiving PD-1/PD-L1 blockade, with grade 3–4 events in roughly 1%–3% [2, 3]. Anti-PD-1 hepatitis may be hepatocellular, mixed, or cholestatic, and management requires exclusion of alternative causes together with corticosteroids when abnormalities are persistent or clinically significant [4–8]. Data supporting retreatment after recurrent hepatitis remain limited, particularly for switching from pembrolizumab to nivolumab after repeated same-agent rechallenge failure [9, 10].