title: Utility of cell blocks obtained by catheter aspiration via a guide sheath during endobronchial ultrasonography.
abstract: BACKGROUND
  The demand for adequate tissue samples for both morphological assessment and molecular studies on lung cancer treatment has increased. The aim of this study was to evaluate whether cell blocks (CBs) prepared from endobronchial ultrasonography with guide sheath (EBUS-GS) rinsing following catheter aspiration provide additional information.
  
  
  METHODS
  We produced CBs from rinse fluid obtained from washing the inside of the sheath with saline after conventional EBUS-GS between May 2012 and April 2013. During the first 7 months, the sheath was aspirated with 20mL of negative pressure while moving the catheter back and forth [aspiration group (Asp)]. During the next 5 months, the sheath was not aspirated, but only rinsed out [conventional group (Con)]. Patients diagnosed with lung cancer by EBUS-GS and/or CBs were identified and evaluated. The diagnostic rate of each sampling method was compared between the two groups. The number of tumor cells was also compared between the CB and EBUS-guided transbronchial lung biopsy (EBUS-TBB) groups.
  
  
  RESULTS
  EBUS-GS was performed on 113 patients. Fifty-five patients were included in this study (Asp=30, Con=25). The diagnostic yield of CBs in Asp was higher than that in Con (56.7% vs 32.0%; p=0.06). Asp showed no significant difference in the number of tumor cells between CB and EBUS-TBB. One patient who showed negative EBUS-TBB pathological results but positive CB results was diagnosed only by immunohistological staining of CB.
  
  
  CONCLUSIONS
  CB prepared from EBUS-GS rinsing following catheter aspiration may provide additional information.
authors.affiliation: Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan; Kobe University Hospital Respiratory Center, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan. Electronic address: hazekin@gmail.com.
authors.forename: Nobuko
authors.initials: N
authors.lastname: Hazeki
authors.affiliation: Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan; Kobe University Hospital Respiratory Center, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan. Electronic address: mt0318@med.kobe-u.ac.jp.
authors.forename: Motoko
authors.initials: M
authors.lastname: Tachihara
authors.affiliation: Diagnostic Pathology Department of Pathology, Kobe University Hospital, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan. Electronic address: ryuko@med.kobe-u.ac.jp.
authors.forename: Ryuko
authors.initials: R
authors.lastname: Tsukamoto
authors.affiliation: Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan; Kobe University Hospital Respiratory Center, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan. Electronic address: sun-tara@m3.dion.ne.jp.
authors.forename: Shuntaro
authors.initials: S
authors.lastname: Tokunaga
authors.affiliation: Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan; Kobe University Hospital Respiratory Center, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan. Electronic address: dtamura@med.kobe-u.ac.jp.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Tamura
authors.affiliation: Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan; Kobe University Hospital Respiratory Center, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan. Electronic address: rav2327@yahoo.co.jp.
authors.forename: Haruko
authors.initials: H
authors.lastname: Shinke
authors.affiliation: Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan; Kobe University Hospital Respiratory Center, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan. Electronic address: kkoba@med.kobe-u.ac.jp.
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Kobayashi
authors.affiliation: Diagnostic Pathology Department of Pathology, Kobe University Hospital, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan; Kobe University Hospital Respiratory Center, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan. Electronic address: sakaiyasuhiro@gaia.eonet.ne.jp.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Sakai
authors.affiliation: Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan; Kobe University Hospital Respiratory Center, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan. Electronic address: nishiy@med.kobe-u.ac.jp.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Nishimura
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D044963:Biopsy, Fine-Needle / Q000379:methods*; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology*; D001999:Bronchoscopy / Q000379:methods*; D057785:Catheters; D019160:Endosonography / Q000379:methods*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D018084:Ultrasonography, Interventional / Q000379:methods*
keywords: Aspiration method; Bronchoscopy; Cell block; Endobronchial ultrasonography with a guide sheath; Lung cancer