Biomarker Testing Practices for Non-small Cell Lung Cancer: Survey Insights from South Korean Pathology Laboratories.

[PURPOSE] Molecular biomarker testing is essential for lung cancer management and precision medicine. This study evaluated biomarker testing practices for non-small cell lung cancer across pathology laboratories in South Korea.

[MATERIALS AND METHODS] A nationwide survey of 30 pathology laboratories assessed testing policies, biomarker adoption, testing platforms, next-generation sequencing (NGS) implementation, reporting practices, turnaround times (TATs), and perceived challenges.

[RESULTS] All institutions routinely performed biomarker testing; 20 (66.7%) employed reflex testing at least in part. Tissue was the primary specimen type, and cytology and liquid biopsy specimens were accepted by 90.0% and 46.7% of institutions, respectively. For non-squamous NSCLC, all institutions tested EGFR, ALK, ROS1, and PD-L1, with additional testing for BRAF (86.7%) and KRAS (80.0%); other actionable targets were rarely tested outside NGS. In squamous NSCLC, PD-L1 was routinely assessed, whereas other drivers were tested less frequently. All institutions performed tissue-based NGS using companion diagnostic (CDx) and/or non-CDx platforms, and liquid biopsy-based NGS was available in 46.7% of institutions. Median TATs were 2-3, 5, 9, 19, and 15 days for immunohistochemistry, polymerase chain reaction, fluorescence in situ hybridization, tissue-based NGS, and liquid biopsy-based NGS, respectively. Reported barriers included limited sample availability, workforce shortages, prolonged TATs, regulatory restrictions, and lack of standardization.

[CONCLUSION] Biomarker testing is widely implemented in South Korea, with increasing integration of NGS. Despite alignment with international recommendations, systemic and policy reforms are needed to harmonize workflows, reduce variability, and optimize precision oncology.