title: Endoscopic surveillance of head and neck cancer in patients with esophageal squamous cell carcinoma.
abstract: OBJECTIVE
  Multiple squamous cell carcinomas (SCCs) frequently arise in the upper aerodigestive tract, referred to as the field cancerization phenomenon. The aim of this study was to elucidate the detailed clinical features of second primary head and neck (H&N) SCCs arising in patients with esophageal SCC.
  
  
  METHODS
  A total of 818 patients underwent endoscopic resection for superficial esophageal cancer between January 2006 and December 2013. Of these, 439 patients met our inclusion criteria, and we retrospectively investigated the incidence, primary sites, and stages of second primary H&N SCCs in these patients.
  
  
  RESULTS
  A total of 53 metachronous H&N SCCs developed in 40 patients after a median follow-up period of 46 months (range 9 - 109). The cumulative incidence rates of metachronous H&N SCCs at 3, 5, and 7 years were 5.3 %, 9.7 %, and 17.2 %, respectively. These lesions were frequently located at pyriform sinus or in the posterior wall of the pharynx (70 %, 37/53 lesions). Most of the lesions were detected at an early stage, though 4 lesions were associated with lymph node metastasis when their primary sites were detected (1 postcricoid area, 2 posterior wall of hypopharynx, and 1 lateral wall of oropharynx).
  
  
  CONCLUSIONS
  Patients with esophageal SCC should undergo careful inspection of the pyriform sinus and posterior wall of the pharynx for detection of H&N SCCs. Methods to open the hypopharyngeal space, such as the Valsalva maneuver, should be included in the surveillance program.
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Minoru
authors.initials: M
authors.lastname: Kato
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Ryu
authors.initials: R
authors.lastname: Ishihara
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Kenta
authors.initials: K
authors.lastname: Hamada
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Tonai
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Yamasaki
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Matsuura
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kanesaka
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Sachiko
authors.initials: S
authors.lastname: Yamamoto
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Tomofumi
authors.initials: T
authors.lastname: Akasaka
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Noboru
authors.initials: N
authors.lastname: Hanaoka
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Yoji
authors.initials: Y
authors.lastname: Takeuchi
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Higashino
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Noriya
authors.initials: N
authors.lastname: Uedo
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Iishi