Feasibility of Endobronchial Ultrasound-guided Transbronchial Needle Aspiration Cytology Specimens for Next Generation Sequencing in Non-small-cell Lung Cancer.

INTRODUCTION: Next generation sequencing (NGS) testing of lung cancer is recommended by guidelines, and endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration (TBNA) often provides the only material available for testing. Previous studies have demonstrated successful NGS testing on cell block samples obtained by EBUS; however, cytology smears provide a more reliable sample with better DNA quality for testing. In this study, we aimed to determine the success rate of OncoScreen (50 gene) and OncoPlus (1213 gene) panel NGS testing of cytology samples obtained by EBUS utilizing 22- and 25-gauge needles. METHODS: Fifty-four patients underwent EBUS-TBNA of lung cancer for which NGS testing was requested. Data was analyzed for needle gauge, cytologic assessment, NGS test success, and sample type (cytology smear or cell block) used for testing. RESULTS: Eighty-five NGS tests were ordered on 54 samples. Overall, 95.3% of samples had successful testing. OncoScreen and OncoPlus panels were successful 98.0% and 91.4% of the time, respectively. Cytology smears provided testing material for 85% of the tests. OncoScreen testing was successful in 97.5% and 100% of the 22- and 25-gauge samples, respectively (P = 1.00). OncoPlus testing was successful in 91.3% and 100% of the 22- and 25-gauge samples, respectively (P = 1.00). CONCLUSIONS: NGS can be reliably performed on cytology smears obtained from EBUS-TBNA. The size of the needle does not seem to affect the success rate of small or large panel NGS tests.

Programmed death-ligand 1 testing of lung cancer cytology specimens obtained with bronchoscopy.

BACKGROUND: Programmed death-ligand 1 (PD-L1) expression testing is recommended by guidelines for patients with advanced non-small cell lung cancer (NSCLC). The primary objective of the current study was to determine the success rate of PD-L1 testing from cytology cell block samples obtained by bronchoscopic needle aspiration. The secondary objective was the assessment of the difference in specimen adequacy acquired via needles of different gauges. METHODS: Patients with NSCLC who underwent bronchoscopic needle aspirations for which PD-L1 testing was requested between November 1, 2016, and February 6, 2017, were included in the current analysis. Patients underwent needle aspiration from intrathoracic adenopathy or a pulmonary lesion. Rapid on-site cytology evaluation was performed in all cases. PD-L1 immunohistochemistry was performed using the Abcam anti-PD-L1 antibody 28.8 clone on cell block specimen. RESULTS: A total of 22 patients had PD-L1 testing requested on needle cytology samples obtained via bronchoscopy at the time of initial diagnosis (81.8%) and for progression of disease (18.2%). Twenty patients (90.9%) underwent successful PD-L1 testing. Sample acquisition was via endobronchial ultrasound-guided transbronchial needle aspiration in 72.7% of patients, endobronchial needle aspiration in 18.2% of patients, and peripheral nodule needle aspiration in 9.1% of patients. There was no statistical difference in PD-L1 test success rates between sample methods (P = .99) or needle sizes (P = 1.00). CONCLUSIONS: Bronchoscopically obtained cytology needle-based samples are adequate for PD-L1 testing in patients with NSCLC. There was no difference noted between different needle sizes with regard to adequacy for PD-L1 testing. These findings are relevant for clinicians caring for patients with lung cancer because a vast majority of patients with advanced NSCLC are diagnosed by bronchoscopic needle-based techniques using a variety of commercially available needles. Cancer Cytopathol 2018;126:122-8. © 2017 American Cancer Society.

Pulseless Oximetry: A Preliminary Evaluation.

BACKGROUND: Pulse oximetry fails when pulsations are weak or absent, common in patients with continuous flow left ventricular assist devices (LVADs). We developed a method to measure arterial oxygenation (Sao2) noninvasively in pulseless patients with LVADs. METHODS: The technique involves 5- to 10-s occlusions of radial and ulnar arteries on one hand. A fingertip is transilluminated alternately with light-emitting diodes emitting 660 nm (red) and 905 nm (infrared). During the approximately 1 s after release of occlusion, changing attenuance of each wavelength is measured and their red/infrared arterial blood attenuance ratio (R/IR) calculated. We studied five normal subjects breathing hyperoxic, normoxic, or hypoxic gas mixtures to establish a calibration curve, using standard pulse oximetry as the gold standard. We also studied seven pulseless patients with LVADs (two studied twice) at clinically determined oxygenation. RESULTS: Normal subject data showed close correlation of oxygen saturation by pulse oximetry (Spo2) with R/IR, (Spo2 = 111 - [26.7 × R/IR]; R2 = 0.975). For patients with LVADs, predicted Sao2 (from the calibration curve) tended to underestimate measured Sao2 (from arterial blood) by a clinically insignificant 1.1 ± 1.6 percentage points (mean ± SD), maximum 3.4 percentage points. CONCLUSIONS: Preliminary results in a small number of patients demonstrate that pulseless oximetry can be used to estimate arterial saturation with acceptable accuracy. A noninvasive oximeter that does not rely on pulsatile flow would be a valuable advance in assessing oxygenation in patients with LVADs, for whom the only current option is arterial puncture, which is painful, risks arterial injury, and only provides a snapshot evaluation of oxygenation.