title: Efficacy of double-scope endoscopic submucosal dissection and long-term outcomes of endoscopic resection for superficial pharyngeal cancer.
abstract: OBJECTIVE
  Owing to increased awareness and use of narrow-band imaging, there are more opportunities to treat superficial pharyngeal cancer (SPC). The present study aimed to describe the short- and long-term outcomes of endoscopic resection (ER) for SPC.
  
  
  METHODS
  This study included 166 consecutive SPC in 113 patients treated during 2006 to 2013 at one referral cancer center. In the first period, we treated patients using endoscopic mucosal resection (EMR), in the second period using conventional ESD (cESD) and in the recent period using double-scope ESD (dsESD), which involves a second thin endoscope for assistance to produce traction. Median follow-up period was 30 months.
  
  
  RESULTS
  All lesions were diagnosed as squamous cell carcinoma. Complete resection rate of cESD and dsESD procedures was 56.4% and 82.3% (P < 0.01), and local recurrence rate was 2.6% and 0.0%, respectively. Procedure duration was significantly shorter for dsESD than for cESD (P < 0.05). Four cases of recurrent lymph node (LN) metastasis were observed; however, all patients with LN metastases survived to a 48-month median interval after neck dissection. Risk factors for LN metastasis included subepithelium invasion, tumor thickness >1000 μm, droplet infiltration, and lymphovascular invasion. Overall survival rate after 5 years was 79.5%; no patients died of SPC. Cumulative rate of metachronous SPC after 5 years was 46.5%.
  
  
  CONCLUSIONS
  ER for SPC is a feasible and effective treatment, although metachronous SPC occurred frequently. For the technique of ER, dsESD was effective.
authors.affiliation: Department of Gastroenterology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Yoshio
authors.affiliation: Department of Gastroenterology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Tsuchida
authors.affiliation: Department of Gastroenterology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Ishiyama
authors.affiliation: Department of Gastroenterology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Masami
authors.initials: M
authors.lastname: Omae
authors.affiliation: Department of Gastroenterology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Hirasawa
authors.affiliation: Department of Gastroenterology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Yorimasa
authors.initials: Y
authors.lastname: Yamamoto
authors.affiliation: Department of Gastroenterology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Junko
authors.initials: J
authors.lastname: Fujisaki
authors.affiliation: Department of Pathology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Sato
authors.affiliation: Department of Head and Neck, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Tohru
authors.initials: T
authors.lastname: Sasaki
authors.affiliation: Department of Head and Neck, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Kawabata
authors.affiliation: Department of Gastroenterology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Igarashi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D015331:Cohort Studies; D020776:Endoscopes, Gastrointestinal; D000069916:Endoscopic Mucosal Resection / Q000295:instrumentation*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology / Q000473:pathology; D010610:Pharyngeal Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D016896:Treatment Outcome
keywords: double-scope endoscopic submucosal dissection (dsESD); endoscopic resection (ER), long-term prognosis, lymph node metastasis, superficial pharyngeal cancer