title: Perianal adenocarcinoma associated with anal fistula: a report of 11 cases in a single institution focusing on treatment and literature review.
abstract: OBJECTIVE
  Perianal adenocarcinoma associated with anal fistula is a rare disease with a poor prognosis. The relatively small number of patients with this disease has led to a lack of any consensus regarding diagnosis and appropriate treatment. The purpose of this study was to present our experience of 11 cases of this disease, and to highlight its clinical features, treatments and outcomes.
  
  
  METHODS
  The patients were divided into three groups according to the modality of treatment. Four patients received surgical resection without preoperative therapy (operation group), 3 patients were treated with radiotherapy prior to surgery (RT group), and 4 were treated with combined chemoradiation therapy prior to surgery (CRT group).
  
  
  RESULTS
  The resection stump was pathologically negative for cancer in 6 (85.7%) patients in RT or CRT group, and 3 of 6 are alive with no evidence of disease recurrence. However, the resection stump was negative in only 1 (25%) patient in the operation group. Moreover, among the patients who underwent neoadjuvant RT/CRT and abdominoperineal resection with a cancer-free resection stump, 2 patients with postoperative adjuvant therapy had no recurrence of disease.
  
  
  CONCLUSIONS
  Multimodality therapy including neoadjuvant RT or CRT and adjuvant chemotherapy is considered to be effective for treatment of this disease.
authors.affiliation: Department of Surgical Oncology, Faculty of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Kumiko
authors.initials: K
authors.lastname: Hongo
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Kazama
authors.forename: Eiji
authors.initials: E
authors.lastname: Sunami
authors.forename: Joji
authors.initials: J
authors.lastname: Kitayama
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Watanabe
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis* / Q000473:pathology / Q000628:therapy*; D000328:Adult; D000368:Aged; D001005:Anus Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000628:therapy*; D014408:Biomarkers, Tumor / Q000097:blood; D001706:Biopsy; D003131:Combined Modality Therapy; D006801:Humans; D008875:Middle Aged; D012003:Rectal Fistula / Q000175:diagnosis* / Q000473:pathology / Q000628:therapy*
chemical_list: D014408:Biomarkers, Tumor