title: Interstitial brachytherapy as a boost to patients with anal carcinoma and poor response to chemoradiation: Single-institution long-term results.
abstract: To analyze the efficacy of a protocol-based brachytherapy (BT) boost after external beam radiation therapy (EBRT) with simultaneous chemotherapy in patients with anal carcinoma.
  
  
  
  About 190 patients have been analyzed. Around 143 patients were identified with a good clinical response at the end of EBRT. Another 47 patients received an additional BT boost to the residual tumor at 6 weeks after end of chemoradiation.
  
  
  
  The 5-year incidence of local recurrence was 24% in patients with BT boost and 19% in patients without BT boost (p = 0.238). The 5-year disease-free survival rate, overall survival rate, and colostomy-free survival rate were 64% and 75% and 76.1% in the BT group and 69% (p = 0.212), 72% (p = 0.924), and 82.7% (p = 0.488) in the non-BT group. We found no differences in late toxicity between the groups.
  
  
  
  For patients with anal cancer with not a good response to 50-59 Gy EBRT with simultaneous chemotherapy, the further dose escalation using the BT boost up to a mean of 67.5 Gy seems to improve the clinical outcome to the same level as observed in patients with a good response to ERBT, without an increase in late side effects.
authors.affiliation: Department of Radiation Oncology, University Hospital of Erlangen, Erlangen, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Gryc
authors.affiliation: Department of Radiation Oncology, University Hospital of Erlangen, Erlangen, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Ott
authors.affiliation: Department of Radiation Oncology, University Hospital of Erlangen, Erlangen, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Putz
authors.affiliation: Department of Radiation Oncology, University Hospital of Erlangen, Erlangen, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Knippen
authors.affiliation: Department of General Surgery, University Hospital of Erlangen, Erlangen, Germany.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Raptis
authors.affiliation: Department of Radiation Oncology, University Hospital of Erlangen, Erlangen, Germany.
authors.forename: Rainer
authors.initials: R
authors.lastname: Fietkau
authors.affiliation: Department of Radiation Oncology, University Hospital of Erlangen, Erlangen, Germany. Electronic address: vratislav.strnad@uk-erlangen.de.
authors.forename: Vratislav
authors.initials: V
authors.lastname: Strnad
mesh_terms: D000328:Adult; D000368:Aged; D001005:Anus Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D001918:Brachytherapy / Q000379:methods*; D059248:Chemoradiotherapy / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D009367:Neoplasm Staging; D011879:Radiotherapy Dosage; D016019:Survival Analysis; D016896:Treatment Outcome
keywords: Anal cancer; Boost; Brachytherapy; Chemoradiation