title: Elective inguinal node irradiation in early-stage T2N0 anal cancer: prognostic impact on locoregional control.
abstract: OBJECTIVE
  To evaluate the influence of elective inguinal node radiation therapy (INRT) on locoregional control (LRC) in patients with early-stage T2N0 anal cancer treated conservatively with primary RT.
  
  
  METHODS
  Between 1976 and 2008, 116 patients with T2 node-negative anal cancer were treated curatively with RT alone (n=48) or by combined chemoradiation therapy (CRT) (n=68) incorporating mitomycin C and 5-fluorouracil. Sixty-four percent of the patients (n=74) received elective INRT.
  
  
  RESULTS
  Over a median follow-up of 69 months (range, 4-243 months), 97 (84%) and 95 patients (82%) were locally and locoregionally controlled, respectively. Rates for 5-year actuarial local control, LRC, cancer-specific, and overall survival for the entire population were 81.7% ± 3.8%, 79.2% ± 4.1%, 91.1% ± 3.0%, and 72.1% ± 4.5%, respectively. The overall 5-year inguinal relapse-free survival was 92.3% ± 2.9%. Isolated inguinal recurrence occurred in 2 patients (4.7%) treated without INRT, whereas no groin relapse was observed in those treated with INRT. The 5-year LRC rates for patients treated with and without INRT and with RT alone versus combined CRT were 80.1% ± 5.0% versus 77.8% ± 7.0% (P=.967) and 71.0% ± 7.2% versus 85.4% ± 4.5% (P=.147), respectively. A trend toward a higher rate of grade ≥3 acute toxicity was observed in patients treated with INRT (53% vs 31%, P=.076).
  
  
  CONCLUSIONS
  In cases of node-negative T2 anal cancer, the inguinal relapse rate remains relatively low with or without INRT. The role of INRT in the treatment of early-stage anal carcinoma needs to be investigated in future prospective trials.
authors.affiliation: Department of Radiation Oncology, Geneva University Hospital, Geneva, Switzerland. Thomas.Zilli@hcuge.ch
authors.forename: Thomas
authors.initials: T
authors.lastname: Zilli
authors.forename: Michael
authors.initials: M
authors.lastname: Betz
authors.forename: Sabine
authors.initials: S
authors.lastname: Bieri
authors.forename: Frederic
authors.initials: F
authors.lastname: Ris
authors.forename: Bruno
authors.initials: B
authors.lastname: Roche
authors.forename: Arnaud D
authors.initials: AD
authors.lastname: Roth
authors.forename: Abdelkarim S
authors.initials: AS
authors.lastname: Allal
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001005:Anus Neoplasms / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy*; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy*; D002295:Carcinoma, Transitional Cell / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D059248:Chemoradiotherapy / Q000379:methods; D019583:Dose Fractionation, Radiation; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D007264:Inguinal Canal; D015182:Lymphatic Irradiation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D016685:Mitomycin / Q000008:administration & dosage; D009367:Neoplasm Staging; D012189:Retrospective Studies
chemical_list: D016685:Mitomycin; D005472:Fluorouracil