ES 07.02 Guided Bronchoscopy for Peripheral Lung Nodules

Abstract

In the past several years, X-ray fluoroscopy had been commonly employed to determine the lung field during transbronchial biopsy (TBB); however, precise localization of a PPL has not always been possible leading to low diagnostic yield. For ground glass opacities (GGOs), the value of X-ray fluoroscopy even becomes less. The value of virtual X-ray fluoroscopy and CT fluoroscopy has potential but remains to be known. The advent of endobronchial ultrasound (EBUS) has dramatically increased precise bronchoscopic confirmation of the location of a PPL before sampling. In particular, the radial probe EBUS is used to indicate that a lesion has been reached. For solid peripheral pulmonary lesions (PPLs), Kurimoto et al have described three major types of echogenicities that might differentiate between benignity and malignancy. For GGOs, we have observed constant radial-EBUS patterns that we called blizzard and mixed blizzard signs. Currently, several acquired resistance mechanisms and rare driver oncogenes are identified in non-small cell lung cancer (NSCLC) relapses. Re-biopsy increases valuable information to guide treatment strategies, but the utility and feasibility of bronchoscopic re-biopsy especially endobronchial ultrasound (EBUS) guided re-biopsy has not been investigated. We recently reported the utility of bronchoscopic (EBUS-guided) re-biopsy for detecting the mutation in NSCLC. Re-biopsy by both EBUS-TBNA and EBUS-GS were useful and safe sampling procedures for mutation analysis of EGFR-TKI resistant NSCLC. Another alternative approach, specifically liquid biopsy, now present as a crucial point in the field. Liquid biopsy has grown in importance because the genetic profile of tumors can affect how well they respond to a certain treatment. A recent paper showed that the concordance between re-biopsy and liquid biopsy, including plasma DNA and circulating tumor cell, was 57–60%. The usefulness of monitoring T790M status in liquid biopsy was already reported. Although liquid biopsy has the potential to detect new mutations after chemotherapy, several reports have demonstrated some difficulties in detecting tumor-derived mutations in plasma. Therefore, liquid biopsy and re-biopsy may be considered to be complementary methods of mutation analysis. I would like to share our data and actual cases in this talk. re-biopsy, transbronchial needle aspiration through a guide sheath (GS-TBNA), virtual bronchoscopic navigation (VBN)View Large Image Figure ViewerDownload Hi-res image Download (PPT)