title: Endoscopic and clinical evaluation of treatment and prognosis of Cronkhite-Canada syndrome: a Japanese nationwide survey.
abstract: BACKGROUND
  First reported in 1955, Cronkhite-Canada syndrome (CCS), a rare syndrome characterized by ectodermal abnormalities and inflammatory changes of the gastrointestinal tract mucosa, has been associated with a poor prognosis and life-threatening malignant complications. In a large population survey, we endeavored to characterize the course and treatment outcome of CCS through clinical and endoscopic assessment, and to explore its optimal treatment and surveillance strategy.
  
  
  METHODS
  A retrospective analysis of 210 patients with CCS was conducted via a questionnaire-based nationwide survey of 983 teaching hospitals located throughout Japan. We assessed clinical features, endoscopic findings, treatments used, and short- and long-term outcomes.
  
  
  RESULTS
  The average age at diagnosis was 63.5 years. In all cases, upper or lower gastrointestinal tract polyposis was confirmed, accompanied by characteristic ectodermal abnormalities. Of the treatments used, oral corticosteroids (30-49 mg/day) were the most effective treatment for active disease, with adjunctive nutritional support considered beneficial. With corticosteroid treatment, abdominal symptoms were relieved within a few months, whereas polyp regression often required more than 6 months. Maintenance of endoscopic remission with or without steroids for 3 years significantly lowered the development of CCS-related cancer, compared with relapsers or nonresponders, underscoring the importance of sustained endoscopic remission for cancer prevention.
  
  
  CONCLUSIONS
  The prognosis of CCS has greatly improved through the use of improved medical treatment. Although CCS continues to be relentlessly progressive, carrying a high cancer risk, a sufficient dose and duration of corticosteroid therapy accompanied by nutritional support and periodic endoscopic surveillance appears to improve its natural history.
authors.affiliation: Department of Internal Medicine, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama, 359-8513, Japan. chikakow@ndmc.ac.jp.
authors.forename: Chikako
authors.initials: C
authors.lastname: Watanabe
authors.affiliation: Department of Internal Medicine, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama, 359-8513, Japan.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Komoto
authors.affiliation: Department of Internal Medicine, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama, 359-8513, Japan.
authors.forename: Kengo
authors.initials: K
authors.lastname: Tomita
authors.affiliation: Department of Internal Medicine, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama, 359-8513, Japan.
authors.forename: Ryota
authors.initials: R
authors.lastname: Hokari
authors.affiliation: Department of Pathology and Laboratory Medicine, Hirosaki City Hospital, Aomori, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: Department of Gastroenterology, Fujita Health University, Aichi, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Hirata
authors.affiliation: Center for Advanced IBD Research and Treatment, Kitasato Institute Hospital, Tokyo, Japan.
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Hibi
authors.affiliation: Greater Los Angeles VA Medical Center and Department of Medicine and Department of Surgery, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA.
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Kaunitz
authors.affiliation: Department of Internal Medicine, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama, 359-8513, Japan.
authors.forename: Soichiro
authors.initials: S
authors.lastname: Miura
mesh_terms: D000284:Administration, Oral; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology*; D044483:Intestinal Polyposis / Q000175:diagnosis / Q000473:pathology / Q000628:therapy*; D007564:Japan; D008297:Male; D008875:Middle Aged; D018529:Nutritional Support / Q000379:methods; D011379:Prognosis; D012008:Recurrence; D012074:Remission Induction; D012189:Retrospective Studies; D011795:Surveys and Questionnaires; D013997:Time Factors
chemical_list: D000305:Adrenal Cortex Hormones
keywords: Acquired gastrointestinal polyposis syndrome; Colon cancer; Gastric cancer; Malnutrition