title: Incidence and risk factors of synchronous colorectal cancer in patients with esophageal cancer: an analysis of 480 consecutive colonoscopies before surgery.
abstract: BACKGROUND
  The precise incidence rates of multiple primary colorectal cancers in esophageal cancer patients are unknown.
  
  
  METHODS
  In total, 480 consecutive patients with esophageal cancers surgically resected in the Kumamoto University Hospital received preoperative total colonoscopy for the assessment of colorectal disease between April 2005 and February 2016. We retrospectively investigated the occurrence of synchronous colorectal cancer with esophageal cancer. In addition, we examined the risk factors for the incidence of multiple primary colorectal cancers.
  
  
  RESULTS
  Of the 480 patients, 14 (2.9 %) had synchronous colorectal cancers, 13 had well-differentiated tubular adenocarcinomas, and 1 had papillary adenocarcinoma. Other 14 patients had metachronous colorectal cancer. The current incidence rates of synchronous and total (both synchronous and metachronous) colorectal cancers outnumbered those in normal healthy population and those in esophageal cancer patients which previously reported by The Japan Esophageal Society. The age ≥70 years (hazard ratio 4.82, 95 % confidence interval 1.473-15.78; p = 0.009) and Brinkman index ≥800 (hazard ratio 3.47, 95 % confidence interval 1.056-11.37; p = 0.040) were the independent risk factors for the incidence of synchronous colorectal cancer. They were also the independent risk factors for the incidence of total colorectal cancer.
  
  
  CONCLUSIONS
  The results of the present study suggested that pretreatment screening with total colonoscopy is meaningful for patients with esophageal cancer, because the frequency of synchronous colorectal cancer was not negligible. Particularly, in patients >70 years and with history of heavy smoking, pretreatment colonoscopy might be necessary.
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan.
authors.forename: Naoya
authors.initials: N
authors.lastname: Yoshida
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan.
authors.forename: Yuka
authors.initials: Y
authors.lastname: Tamaoki
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Baba
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Sakamoto
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Miyamoto
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Iwatsuki
authors.affiliation: Department of Gastroenterology and Hepatology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Shono
authors.affiliation: Department of Gastroenterology and Hepatology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Miyamoto
authors.affiliation: Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Imuta
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan.
authors.forename: Junji
authors.initials: J
authors.lastname: Kurashige
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sawayama
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan.
authors.forename: Ryuma
authors.initials: R
authors.lastname: Tokunaga
authors.affiliation: Department of Gastroenterological Surgery, Cancer Institute Hospital of Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo, 135-8550, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Watanabe
authors.affiliation: Department of Gastroenterology and Hepatology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Sasaki
authors.affiliation: Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan.
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Yamashita
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan. hdobaba@kumamoto-u.ac.jp.
authors.forename: Hideo
authors.initials: H
authors.lastname: Baba
mesh_terms: D000230:Adenocarcinoma / Q000453:epidemiology / Q000473:pathology / Q000601:surgery; D000328:Adult; D000367:Age Factors; D000368:Aged; D003113:Colonoscopy / Q000379:methods / Q000706:statistics & numerical data; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000453:epidemiology / Q000473:pathology; D055088:Early Detection of Cancer / Q000379:methods / Q000706:statistics & numerical data; D004938:Esophageal Neoplasms / Q000453:epidemiology / Q000473:pathology / Q000601:surgery; D016629:Esophagectomy / Q000379:methods / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009378:Neoplasms, Multiple Primary / Q000453:epidemiology / Q000473:pathology; D012189:Retrospective Studies; D012307:Risk Factors
keywords: Colonoscopy; Colorectal cancer; Esophageal cancer; Esophagectomy; Multiple primary cancer