• Rie Sakakibara, Kentaro Inamura, Yuichi Tambo, Hironori Ninomiya, Satoru Kitazono, Noriko Yanagitani, Atsushi Horiike, Fumiyoshi Ohyanagi, Yosuke Matsuura, Masayuki Nakao, Mingyon Mun, Sakae Okumura, Naohiko Inase, Makoto Nishio, Noriko Motoi, and Yuichi Ishikawa.
• Division of Pathology, The Cancer Institute, Department of Pathology, The Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan; Department of Integrated Pulmonology, Tokyo Medical and Dental University, Tokyo, Japan.
• Clin Lung Cancer. 2017 Sep 1; 18 (5): 527-534.e1.

BackgroundBecause most lung cancers are diagnosed at advanced stages, we are forced to conduct molecular testing using small biopsy samples. Endobronchial ultrasound-transbronchial needle aspiration (EBUS-TBNA) is emerging as a minimally invasive biopsy technique. Here, we examined the usefulness of EBUS-TBNA to evaluate programmed death-ligand 1 (PD-L1) expression in lung cancer.MethodsUsing 97 consecutive cases of lung cancer diagnosed by EBUS-TBNA, from which 20 transbronchial biopsy (TBB) samples were available, we evaluated the number and morphological intactness of tumor cells in EBUS-TBNA and TBB samples. Additionally, given the intratumoral heterogeneity in primary lesions and the small sample size of biopsies, we also compared the tumor PD-L1 expression between the biopsy samples and the corresponding surgical materials.ResultsEBUS-TBNA collected a significantly larger number of tumor cells than TBB (P < .001); the median number (interquartile range) of cells was 1149 (379-3334) in EBUS-TBNA and 435 (218-1085) in TBB. The crush rate in EBUS-TBNA was significantly lower than in TBB (P < .001). These showed the excellence of EBUS-TBNA. Additionally, PD-L1 positivity of EBUS-TBNA showed a good concordance with the corresponding primary tumor (r = 0.75; P = .086; n = 6) as well as with lymph node metastasis (r = 0.93; P = .02; n = 5). Moreover, PD-L1 positivity between EBUS-TBNA and TBB (n = 16), TBB and the corresponding primary tumor (n = 41), and lymph node metastasis and the corresponding primary tumor (n = 47) showed a moderate correlation (all r > 0.48; all P < .001), strengthening the potential concordance between EBUS-TBNA and primary tumor in PD-L1 positivity.ConclusionOur study suggests EBUS-TBNA as a promising method to evaluate PD-L1 expression in lung cancer.Copyright © 2017 Elsevier Inc. All rights reserved.

23 keywords...

hide…