PD-L1 after neoadjuvant therapy: an adjuvant treatment dilemma

Introduction: Evidence supporting adjuvant immunotherapy after neoadjuvant anti-PD-1 treatment remains limited outside perioperative regimens evaluated in clinical trials. Case report: A 66-year-old man with stage IIIB (cT3N2M0; 8th edition) squamous non-small cell lung cancer and baseline PD-L1 expression of 30% received three cycles of carboplatin-paclitaxelnivolumab. Surgical pathology following right upper lobectomy showed a major pathological response, with less than 10% viable tumor cells and PD-L1 expression increased to 90%. Discussion: Adjuvant anti-PD-L1 therapy was not administered given the uncertainty regarding its expected benefit. Conclusion: This case highlights the dynamic nature of PD-L1 as a biomarker and the lack of conclusive data to identify patients who may benefit from adjuvant immunotherapy after neoadjuvant anti-PD-1 treatment in this setting.