title: Endobronchial ultrasound with a guide sheath for small malignant pulmonary nodules: a retrospective comparison between central and peripheral locations.
abstract: OBJECTIVE
  Radial endobronchial ultrasound with a guide sheath (EBUS-GS) has improved the diagnostic accuracy of transbronchial biopsy (TBB) for malignant peripheral pulmonary nodules (PPNs). Many underscore the importance of tumor localization but reproducible results on other aspects that affect yield are few. We aimed to analyze the diagnostic performance of TBB with EBUS-GS and to know what group of patients can benefit most.
  
  
  METHODS
  The database of patients with malignant PPNs (≤30 mm) who underwent EBUS-GS TBB at the National Cancer Center Hospital, Tokyo, Japan from April 2012 to March 2013 was retrospectively reviewed and analysed based on lesion and procedural characteristics.
  
  
  RESULTS
  Most PPNs (N=212) were adenocarcinoma, measuring 20 mm [mean, standard deviation (SD) 5.45]. Overall diagnostic accuracy was 67.5% (143 of 212 cases). Factors that significantly affected and predicted diagnostic success were EBUS probe within (P=0.001) and parenchymal location that was not adjacent to the costal visceral pleura (P=0.001). When combined, these variables achieved an 87% (59 of 68 lesions) diagnostic yield. CT scan characteristic, lesion size, lobe location, and GS size were non-contributory.
  
  
  CONCLUSIONS
  EBUS-GS TBB is an acceptable diagnostic method for small peripheral lung cancer. It can be maximized for PPNs that are away from the pleura and when the EBUS probe can be placed within the lesion.
authors.affiliation: 1 Department of Endoscopy, Respiratory Endoscopy Division, National Cancer Center Hospital, Tokyo 104-0045, Japan ; 2 Department of Internal Medicine, Division of Pulmonary Medicine, Kameda General Hospital, Chiba 296-8602, Japan.
authors.forename: Christine
authors.initials: C
authors.lastname: Chavez
authors.affiliation: 1 Department of Endoscopy, Respiratory Endoscopy Division, National Cancer Center Hospital, Tokyo 104-0045, Japan ; 2 Department of Internal Medicine, Division of Pulmonary Medicine, Kameda General Hospital, Chiba 296-8602, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Sasada
authors.affiliation: 1 Department of Endoscopy, Respiratory Endoscopy Division, National Cancer Center Hospital, Tokyo 104-0045, Japan ; 2 Department of Internal Medicine, Division of Pulmonary Medicine, Kameda General Hospital, Chiba 296-8602, Japan.
authors.forename: Takehiro
authors.initials: T
authors.lastname: Izumo
authors.affiliation: 1 Department of Endoscopy, Respiratory Endoscopy Division, National Cancer Center Hospital, Tokyo 104-0045, Japan ; 2 Department of Internal Medicine, Division of Pulmonary Medicine, Kameda General Hospital, Chiba 296-8602, Japan.
authors.forename: Junko
authors.initials: J
authors.lastname: Watanabe
authors.affiliation: 1 Department of Endoscopy, Respiratory Endoscopy Division, National Cancer Center Hospital, Tokyo 104-0045, Japan ; 2 Department of Internal Medicine, Division of Pulmonary Medicine, Kameda General Hospital, Chiba 296-8602, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Katsurada
authors.affiliation: 1 Department of Endoscopy, Respiratory Endoscopy Division, National Cancer Center Hospital, Tokyo 104-0045, Japan ; 2 Department of Internal Medicine, Division of Pulmonary Medicine, Kameda General Hospital, Chiba 296-8602, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Matsumoto
authors.affiliation: 1 Department of Endoscopy, Respiratory Endoscopy Division, National Cancer Center Hospital, Tokyo 104-0045, Japan ; 2 Department of Internal Medicine, Division of Pulmonary Medicine, Kameda General Hospital, Chiba 296-8602, Japan.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Tsuchida
keywords: Endobronchial ultrasound (EBUS); ground glass opacity (GGO); lung cancer; pulmonary nodule (PN); transbronchial biopsy (TBB)