Acquisition and Processing of Endobronchial Ultrasound-guided Transbronchial Needle Aspiration Specimens in the Era of Targeted Lung Cancer Chemotherapy

Abstract

Recent advances in therapy for non-small cell lung carcinoma have shown that a personalized approach to treatment has the potential to significantly reduce lung cancer mortality. Concurrently, endoscopic ultrasound transbronchial needle aspiration has emerged as an accurate and sensitive tool for the diagnosis and staging of this disease. As knowledge of the molecular mechanisms that drive lung cancer progression increases, the amount of information that must be derived from a tumor specimen will also increase. Recent clinical studies have demonstrated that small specimens acquired by endoscopic ultrasound transbronchial needle aspiration are sufficient for molecular testing if specimen acquisition and processing are done with these needs in mind. Optimum use of this procedure requires a coordinated effort between the bronchoscopist and the cytopathologist to collect and triage specimens for diagnostic testing. When feasible, rapid onsite evaluation should be performed to assess the specimen for both diagnostic quality and quantity and to allocate the specimen for cell-block and possible immunohistochemistry and molecular studies. It is necessary for pulmonologists and bronchoscopists to understand the rationale for histologic and molecular testing of lung cancer diagnostic specimens and to ensure that specimens are acquired and processed in a fashion that provides information from small cytologic specimens that is sufficient to guide treatment in this era of targeted therapy.Keywords: lung cancer; bronchoscopy; cytology; EGFR; molecular testing Lung cancer remains the leading cause of cancer mortality in the world, with 157,000 deaths expected in the United States in 2010 (1). Despite the large death toll, there are reasons to be cautiously optimistic for a future with fewer lung cancer deaths. Recent advances in clinical and bench research directed toward diagnostics and therapy have led to significant and often dramatic impacts on patient outcomes (2). These developments suggest that a personalized approach to treating lung cancer has the potential to significantly reduce lung cancer mortality. Current standards of care for advanced non-small cell lung carcinoma (NSCLC) treatment assign therapy on the basis of histology and on the basis of epidermal growth factor receptor (EGFR) status for lung adenocarcinoma. This paradigm shift away from homogenous therapy of NSCLC converges with the increased use of bronchoscopic approaches for lung cancer diagnosis and staging, thus enhancing the important role for pulmonary physicians in lung cancer management. It is essential that the bronchoscopist understand the importance of acquiring and processing diagnostic specimens in a manner that provides sufficient information to guide treatment in this era of personalized therapy. This article reviews the rationale for acquiring specific histologic and molecular data from lung cancer biopsies, and recommends multidisciplinary procedures for specimen acquisition and processing that can optimize the yield of pulmonary diagnost...

An Official American Thoracic Society/European Respiratory Society Statement: The Role of the Pulmonologist in the Diagnosis and Management of Lung Cancer

“…In certain countries and settings, they provide medical treatment for the cancer (e.g., chemotherapy and biologics), endobronchial treatment (e.g., brachytherapy), general supportive care, and terminal care. (2). These targeted therapies are a promising new approach that requires meticulous attention by pulmonologists to provide adequate tissue sampling through the competent use of endoscopic procedures.…”

“…Potentially all treatment decisions, at the time of diagnosis and later, will be based on the information obtained from that specimen. Therefore, it is essential that the specimen collection and processing procedures be optimized to ensure that the quality and quantity of the specimen are adequate to provide answers to all the questions that may be asked (2).…”

Molecular Biology of Lung Cancer

“…26 These fi ndings have prompted a major shift toward targeted therapy in lung cancer management, as detailed by Socinski et al 27 in the article, "Treatment of Stage IV Non-small Cell Lung Cancer," in the American College of Chest Physicians Lung Cancer Guidelines, thus mandating that diagnostic specimens be acquired and processed in a fashion that permits the histologic subtyping of NSCLC. 28 In studies using immunostains to subtype NSCLC in cytologic specimens, Loo et al 29 and Nicholson et al 30 showed that thyroid transcription factor-1 and mucin vs p63 stains are the best stains for detecting adenocarcinoma vs SCC, respectively . However, none of the antibodies used in immunohistochemistry is 100% specifi c and sensitive for this differential diagnosis.…”

The introduction of electromagnetic navigation bronchoscopy for the diagnosis of small pulmonary peripheral lesions in an Asian population

“…Presently, lung cancer treatment is based on the histologic subtyping of NSCLC (13,14). Our study strongly suggests that ENB is an outstanding technique that can aid pulmonary physicians in small lung lesions diagnosis.…”