Cell block samples from endobronchial ultrasound transbronchial needle aspiration provide sufficient material for ancillary testing in lung cancer—a quaternary referral centre experience

Abstract

Background: Rapid on site examination (ROSE) is encouraged at endobronchial ultrasound transbronchial needles aspiration (EBUS-TBNA) to improve diagnostic yield. Due to new therapeutic options in lung cancer, it is not sufficient to merely distinguish between non-small cell lung carcinoma (NSCLC) and small cell lung carcinoma (SCLC). Immunohistochemistry (IHC) distinction is now standard practice, as well as additional molecular testing where clinically indicated. We investigated the diagnostic yield of on-site smears vs. cell block and the provision of cellular material for ancillary testing at our centre.Methods: A retrospective audit of all EBUS-TBNA procedures performed until July 2012 was undertaken.Diagnostic yield on smears versus cell block was recorded. Cell blocks were reviewed by an experienced pathologist to determine diagnostic accuracy and whether IHC and molecular testing were possible. Results: In total, 234 procedures were recorded with 101 (43.2%) malignant cases, 107 (45.7%) benign cases and an initial 26/234 (11.1%) insufficient for diagnosis of which 11/234 (4.7%) were false negatives for malignancy after further follow up. The average number of passes was 4.5. For malignancies, smear diagnosis was possible in 95% (96/101) of cases and cell block diagnosis in 93.5% (87/93) of cases. There was sufficient material for IHC in 97.7% (85/87) of malignant cases. In 79.3% (69/87) of NSCLCs molecular testing for epidermal growth factor receptor (EGFR) mutation analysis was theoretically possible on samples obtained. Conclusions: Cell blocks are not inferior to smears for diagnostic accuracy and provide sufficient samples for histology. However, ROSE assists the physician on how best to manage samples for ancillary testing.

Rapid On-Site Evaluation of Endobronchial Ultrasound–Guided Transbronchial Needle Aspirations for the Diagnosis of Lung Cancer: A Perspective From Members of the Pulmonary Pathology Society

“…Rapid onsite evaluation helps in triaging material for molecular and cytogenetic studies, including EGFR and KRAS mutations and ALK and ROS1 rearrangement. 20,52,[60][61][62][63] The material obtained by EBUS-TBNA is suitable for molecular analysis in more than 90% of the samples. 64,65 Specimens were satisfactory and adequate for molecular analysis in 95% of all cases in the study by Yarmus et al, 20 where they used material for EGFR and KRAS sequencing and ALK fluorescence in situ hybridization analysis.…”

Lung adenocarcinoma: from molecular basis to genome-guided therapy and immunotherapy

“…In this regard, multiple studies have confirmed the utility of even cytological samples obtained by endobronchial ultrasound (EBUS) to perform the molecular study (99)(100)(101)(102). However, although a cell block can be obtained by EBUS in most cases (103), there is still controversy on its advantages and disadvantages with respect to the on-site smear in identifying driver alterations (104,105).…”

Adequacy of endosonography‐derived samples from peribronchial or periesophageal intrapulmonary lesions for the molecular profiling of lung cancer

“…Concomitantly, key changes in the treatment of lung cancer (ie, targeted therapy and immunotherapy) have rendered crucial the systematic search for specific driver molecular alterations (ie, EGFR mutation and ALK / ROS1 rearrangements) and other predictive biomarkers (PD‐L1) in patients with advanced disease . As a consequence, the suitability of EBUS‐TBNA samples from lymphadenopathy for the molecular analysis of cancer samples has been investigated in several individual studies . A recent systematic review with meta‐analysis, which included 33 studies and 2869 patients, concluded that EBUS‐TBNA from lymphadenopathy has a high yield (>90%) for EGFR and ALK testing .…”

“…5,6 As a consequence, the suitability of EBUS-TBNA samples from lymphadenopathy for the molecular analysis of cancer samples has been investigated in several individual studies. [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] A recent systematic review with meta-analysis, which included 33 studies and 2869 patients, concluded that EBUS-TBNA from lymphadenopathy has a high yield (>90%) for EGFR and ALK testing. 27 However, data on the yield for ROS1 and PD-L1, as well as those on the suitability of EBUS-TBNA samples for next-generation sequencing were scant and prevented the authors from drawing definitive conclusions.…”