Tumor Location Significantly Correlates With PD-L1 Status in Patients With Small Sized Non-small Cell Lung Cancer

Area of Science:

• Oncology
• Immunotherapy
• Thoracic Surgery

Background:

• Predicting programmed death-ligand 1 (PD-L1) expression is vital for guiding treatment in resectable lung cancer.
• Tumor location differences in non-small cell lung cancer (NSCLC) have been noted, but their impact on PD-L1 expression was unexamined.

Purpose of the Study:

• To investigate the relationship between clinical factors, including tumor location, and PD-L1 expression status in NSCLC.
• To identify predictive factors for PD-L1 expression to inform treatment strategies.

Main Methods:

• Included 245 NSCLC patients with tumors ≤3 cm and consolidation tumor ratio (CTR) <0.5.
• Classified tumors as central or peripheral based on computed tomography location.
• Assessed PD-L1 expression using 22C3 antibody immunohistochemistry, categorizing it as negative (TPS <1%) or positive (TPS ≥1%).

Main Results:

• PD-L1 expression significantly correlated with CTR, histology type, and tumor location (p<0.05).
• Multivariate analysis identified CTR (>0.94), non-adenocarcinoma, and central lesions as independent predictors of positive PD-L1 expression.
• A predictive scoring system based on these factors showed a stepwise increase in PD-L1 positivity with higher scores.

Conclusions:

• PD-L1 expression status is significantly correlated with CTR, histological type, and tumor location in NSCLC.
• This study is the first to demonstrate a significant link between PD-L1 expression and tumor location in NSCLC.
• Differences in the tumor microenvironment influenced by location may affect PD-L1 expression in cancer cells.