title: Comparison of endoscopic stenting for malignant biliary obstruction: A single-center study.
abstract: OBJECTIVE
  To evaluate the efficacy and safety of single-step endoscopic placement of self-expandable metallic stents (SEMS) for treatment of obstructive jaundice.
  
  
  METHODS
  A retrospective study was performed among 90 patients who underwent transpapillary biliary metallic stent placement for malignant biliary obstruction (MBO) between April 2005 and October 2012. The diagnosis of primary disease and MBO was based on abdominal ultrasound, computed tomography, magnetic resonance imaging, endoscopic ultrasound, endoscopic retrograde cholangiopancreatography with brush cytology, biopsy, and/or a combination of these modalities. The type of SEMS (covered or non-covered, 8 mm or 10 mm in diameter) was determined by the endoscopist. Ninety patients were divided into two groups: group 1 (49 patients) who underwent a single-step SEMS placement and group 2 (41 patients) who underwent a two-step SEMS placement. The technical success rate, complication rate, stent patency, and patient survival rate were compared between the groups. In addition, to identify the clinical prognostic factors associated with patient survival, the following variables were evaluated in Cox-regression analysis: gender, age, etiology of MBO (pancreatic cancer or non-pancreatic cancer), clinical stage (IVb; with distant metastases or IVa >; without distant metastases), chemotherapy (with or without), patency of the stent, and the use of single-step or two-step SEMS.
  
  
  RESULTS
  Immediate technical success was achieved in 93.9% (46/49) in group 1 and in 95.1% (39/41) in group 2, with no significant difference (P = 1.0). Similarly, there was no difference in the complication rates between the groups (group 1, 4.1% and group 2, 4.9%; P = 0.62). Stent failure was observed in 10 cases in group 1 (20.4%) and in 16 cases in group 2 (39.0%). The patency of stent and patient survival revealed no difference between the two groups with Kaplan-Meier analysis, with a mean patency of 111 ± 17 d in group 1 and 137 ± 19 d in group 2 (P = 0.91), and a mean survival of 178 ± 35 d in group 1 and 222 ± 23 d in group 2 (P = 0.57). On the contrary, the number of days of hospitalization associated with first-time SEMS placement in group 1 was shorter when compared with that number in group 2 (28 vs 39 d; P < 0.05). Multivariate analysis revealed that a clinical stage of IVa > (P = 0.0055), chemotherapy (P = 0.0048), and no patency of the stent (P = 0.011) were independent prognostic factors associated with patient survival.
  
  
  CONCLUSIONS
  Our results showed that single-step endoscopic metal stent placement was safe and effective for treating obstructive jaundice secondary to various inoperable malignancies.
authors.affiliation: Ryuichi Yamamoto, Masatomo Takahashi, Yasuyo Osafune, Katsuya Chinen, Shingo Kato, Sumiko Nagoshi, Koji Yakabi, Department of Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, Saitama 350-8550, Japan.
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Yamamoto
authors.affiliation: Ryuichi Yamamoto, Masatomo Takahashi, Yasuyo Osafune, Katsuya Chinen, Shingo Kato, Sumiko Nagoshi, Koji Yakabi, Department of Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, Saitama 350-8550, Japan.
authors.forename: Masatomo
authors.initials: M
authors.lastname: Takahashi
authors.affiliation: Ryuichi Yamamoto, Masatomo Takahashi, Yasuyo Osafune, Katsuya Chinen, Shingo Kato, Sumiko Nagoshi, Koji Yakabi, Department of Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, Saitama 350-8550, Japan.
authors.forename: Yasuyo
authors.initials: Y
authors.lastname: Osafune
authors.affiliation: Ryuichi Yamamoto, Masatomo Takahashi, Yasuyo Osafune, Katsuya Chinen, Shingo Kato, Sumiko Nagoshi, Koji Yakabi, Department of Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, Saitama 350-8550, Japan.
authors.forename: Katsuya
authors.initials: K
authors.lastname: Chinen
authors.affiliation: Ryuichi Yamamoto, Masatomo Takahashi, Yasuyo Osafune, Katsuya Chinen, Shingo Kato, Sumiko Nagoshi, Koji Yakabi, Department of Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, Saitama 350-8550, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Kato
authors.affiliation: Ryuichi Yamamoto, Masatomo Takahashi, Yasuyo Osafune, Katsuya Chinen, Shingo Kato, Sumiko Nagoshi, Koji Yakabi, Department of Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, Saitama 350-8550, Japan.
authors.forename: Sumiko
authors.initials: S
authors.lastname: Nagoshi
authors.affiliation: Ryuichi Yamamoto, Masatomo Takahashi, Yasuyo Osafune, Katsuya Chinen, Shingo Kato, Sumiko Nagoshi, Koji Yakabi, Department of Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, Saitama 350-8550, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Yakabi
keywords: Endoscopic stenting; Malignant biliary obstruction; Self-expandable metallic stents; Single-step; Two-step