Ng kee Kwong F, et al. - The intent of the authors was to evaluate the connection between PD-L1 expression with pleomorphic morphology and histological patterns in patients with non-small cell lung carcinomas (NSCLC). Prominent variations were reported in PD-L1 expression correlated with histological patterns. Particularly high levels were illustrated in those with pleomorphic features and low/undetectable levels in invasive mucinous adenocarcinomas and the lepidic components of non-mucinous adenocarcinomas. Hence, it was determined that PD-L1 expression analysis was possibly not reliable in a resected adenocarcinoma with a lepidic component when considering immumodulatory therapy for recurrent disease. Re-biopsy or limiting assessment to the invasive component could serve as a more appropriate approach.