title: One compared with two cycles of mitomycin C in chemoradiotherapy for anal cancer: analysis of outcomes and toxicity.
abstract: BACKGROUND
  Concurrent chemoradiation with fluorouracil (5fu) and mitomycin C (mmc) is standard treatment for anal canal carcinoma (acc). The current protocol in Alberta is administration of 5fu and mmc during weeks 1 and 5 of radiation. However, administration of the second bolus of mmc has been based largely on centre preference. Given limited published data on outcomes with different mmc regimens, our objective was to compare the efficacy and toxicity of 1 compared with 2 cycles of mmc in acc treatment.
  
  
  METHODS
  Our retrospective study evaluated 169 acc patients treated with radical chemoradiotherapy between 2000 and 2010 at two tertiary cancer centres. All patients were treated with 2 cycles of 5fu and with 1 cycle (mmc1) or 2 cycles (mmc2) of mmc. Acute toxicities, disease-free (dfs) and overall survival (os) were analyzed.
  
  
  RESULTS
  Baseline demographics, performance status, and stage were similar in the groups of patients who received mmc1 (52%) and mmc2 (48%). Before treatment, median hematologic parameters were comparable, except for white blood cell count, which was higher in the mmc2 group, but within normal range. The 5-year os and dfs were similar (75.1% and 54.2% for mmc1 vs. 70.7% and 44.2% for mmc2, p = 0.98 and p = 0.63 respectively). On multivariate analysis, mmc2 was the factor most strongly associated with specific acute toxicities: grade 3+ leukopenia (hazard ratio: 4.82; p < 0.01), grade 3+ skin toxicity (hazard ratio: 4.76; p < 0.001), and hospitalizations secondary to febrile neutropenia (hazard ratio: 9.91; p = 0.001).
  
  
  CONCLUSIONS
  In definitive chemoradiotherapy for acc, 1 cycle of mmc appears to offer outcomes similar to those achieved with 2 cycles, with significantly less acute toxicity.
authors.affiliation: Department of Radiation Oncology, Tom Baker Cancer Centre, University of Calgary, Calgary, AB.
authors.forename: R
authors.initials: R
authors.lastname: Yeung
authors.affiliation: Department of Surgery, University of Calgary, Calgary, AB.
authors.forename: Y
authors.initials: Y
authors.lastname: McConnell
authors.affiliation: Department of Surgery, University of Calgary, Calgary, AB.
authors.forename: G
authors.initials: G
authors.lastname: Roxin
authors.affiliation: Department of Radiation Oncology, Tom Baker Cancer Centre, University of Calgary, Calgary, AB.
authors.forename: R
authors.initials: R
authors.lastname: Banerjee
authors.affiliation: Department of Internal Medicine and Oncology, University of Calgary, Calgary, AB.
authors.forename: G B Roldán
authors.initials: GB
authors.lastname: Urgoiti
authors.affiliation: Department of Surgery, University of Calgary, Calgary, AB.
authors.forename: A R
authors.initials: AR
authors.lastname: MacLean
authors.affiliation: Department of Surgery, University of Calgary, Calgary, AB.
authors.forename: W D
authors.initials: WD
authors.lastname: Buie
authors.affiliation: Department of Medical Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB.
authors.forename: K E
authors.initials: KE
authors.lastname: Mulder
authors.affiliation: Department of Medical Oncology, Tom Baker Cancer Centre, University of Calgary, Calgary, AB.
authors.forename: M M
authors.initials: MM
authors.lastname: Vickers
authors.affiliation: Department of Radiation Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB.
authors.forename: K J
authors.initials: KJ
authors.lastname: Joseph
authors.affiliation: Department of Radiation Oncology, Tom Baker Cancer Centre, University of Calgary, Calgary, AB.
authors.forename: C M
authors.initials: CM
authors.lastname: Doll
keywords: Chemoradiotherapy; anal cancer