title: Endobronchial ultrasonography for positron emission tomography and computed tomography-negative lymph node staging in non-small cell lung cancer.
abstract: BACKGROUND
  Integrated positron emission tomography (PET) with computed tomography (CT) is a useful modality to investigate lymph node metastases for non-small cell lung cancer, but is less sensitive for normal-sized lymph nodes. We sometimes encounter cases with radiologically normal lymph nodes and unsuspected mediastinal metastases detected by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). However, few studies have investigated staging in patients with radiologically normal mediastina, and the accuracy of EBUS-TBNA staging for radiologically normal mediastina and hila is unclear.
  
  
  METHODS
  This study was a retrospective, single-institution review of a prospectively maintained database at Chiba Cancer Center between May 1, 2008, and September 1, 2013. We analyzed 113 non-small cell lung cancer patients with both CT-negative and PET/CT-negative lymph nodes (N0) in preoperative nodal staging performed by EBUS-TBNA. After preoperative staging was performed, patients with either N0 or N1 clinical staging underwent surgery. Final N factors were determined by mediastinal lymphadenectomy.
  
  
  RESULTS
  In our study, the overall rate of N2 disease was 17.6% (20 of 113). For nodal staging by EBUS-TBNA, the sensitivity, specificity, negative predictive value, and diagnostic accuracy were 35.0% (7 of 20), 100% (93 of 93), 87.7% (93 of 106), and 88.4% (100 of 113), respectively. There were no severe complications from EBUS-TBNA staging.
  
  
  CONCLUSIONS
  The overall rate of unsuspected N2 was not low. EBUS-TBNA was accurate and feasible for preoperative mediastinal nodal staging of non-small cell lung cancer with both CT-negative and PET/CT-negative lymph nodes. The sensitivity of EBUS-TBNA for radiologically normal mediastina and hila was low. Further investigations are required.
authors.affiliation: Department of Thoracic Disease, Chiba Cancer Center, Chiba, Japan. Electronic address: mshingyoji@chiba-cc.jp.
authors.forename: Masato
authors.initials: M
authors.lastname: Shingyoji
authors.affiliation: Department of General Thoracic Surgery, Graduate School of Medicine, Chiba University, Chiba, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Nakajima
authors.affiliation: Department of General Thoracic Surgery, National Hospital Organization Chiba Medical Center, Chiba, Japan.
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Yoshino
authors.affiliation: Department of Thoracic Disease, Chiba Cancer Center, Chiba, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Yoshida
authors.affiliation: Department of Thoracic Disease, Chiba Cancer Center, Chiba, Japan.
authors.forename: Hironori
authors.initials: H
authors.lastname: Ashinuma
authors.affiliation: Department of Thoracic Disease, Chiba Cancer Center, Chiba, Japan.
authors.forename: Meiji
authors.initials: M
authors.lastname: Itakura
authors.affiliation: Department of Respirology, Graduate School of Medicine, Chiba University, Chiba, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Tatsumi
authors.affiliation: Department of Thoracic Disease, Chiba Cancer Center, Chiba, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Iizasa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D044963:Biopsy, Fine-Needle; D001999:Bronchoscopy; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis* / Q000556:secondary; D003937:Diagnosis, Differential; D019160:Endosonography / Q000379:methods*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008482:Mediastinum; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods*; D049268:Positron-Emission Tomography / Q000379:methods*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*