Prospective evaluation of EBUS-TBNA specimens for programmed death-ligand 1 expression in non-small cell lung cancer
Juliana Guarize1, Elena Guerini Rocco2, Filippo de Marinis3
1. Pneumologia Interventistica, Divisione di Chirurgia Toracica, Istituto Europeo di Oncologia - IEO - Istituto di Ricovero e Cura a Carattere Scientifico - IRCCS - Milano, Italia.
Objective:
EBUS-TBNA cytological sampling is routinely performed for pathological diagnosis, mediastinal staging, and molecular testing in lung cancer patients. EBUS-TBNA samples are not formally accepted for testing programmed death-ligand 1 (PD-L1) expression. The objective of the study was to compare the feasibility, reproducibility, and accuracy of PD-L1 expression assessment in cytological specimens and histological samples.
Methods:
We prospectively collected histological (transbronchial forceps biopsy) and cytological (EBUS-TBNA) samples from peribronchial neoplastic lesions during an endoscopic procedure at the same target lesion for the pathological diagnosis and molecular assessment of stage IV non-small cell lung cancer (NSCLC).
Results:
Fifteen patients underwent the procedure. Adequate cytological samples (at least 100 neoplastic cells) were obtained in 12 cases (92.3%). Assessment of PD-L1 expression was similar between histological and cytological samples (agreement rate = 92%). Sensitivity and diagnostic accuracy of EBUS-TBNA cytological specimens were 88.9% and 100%, respectively.
Conclusions:
The evaluation of PD-L1 expression in EBUS-TBNA cytological specimens is feasible and presents good reproducibility when compared with routine histological samples. EBUS-TBNA cytological samples could be used for the assessment of PD-L1 expression in patients with NSCLC as a minimally invasive approach in stage IV NSCLC cancer patients.
