title: Toxicity outcome in patients treated with modulated arc radiotherapy for localized prostate cancer.
abstract: OBJECTIVE
  This study evaluates the acute toxicity outcome in patients treated with RapidArc for localized prostate cancer.
  
  
  BACKGROUND
  Modern technologies allow the delivery of high doses to the prostate while lowering the dose to the neighbouring organs at risk. Whether this dosimetric advantage translates into clinical benefit is not well known.
  
  
  METHODS
  Between December 2009 and May 2012, 45 patients with primary prostate adenocarcinoma were treated using RapidArc. All patients received 1.8 Gy per fraction, the median dose to the prostate gland, seminal vesicles, pelvic lymph nodes and surgical bed was 80 Gy (range, 77.4-81 Gy), 50.4 Gy, 50.4 Gy and 77.4 Gy (range, 75.6-79.2 Gy), respectively.
  
  
  RESULTS
  The time between the last session and the last treatment follow up was a median of 10 months (range, 3-24 months). The incidence of grade 3 acute gastrointestinal (GI) and genitourinary (GU) toxicity was 2.2% and 15.5%, respectively. Grade 2 acute GI and GU toxicity occurred in 30% and 27% of patients, respectively. No grade 4 acute GI and GU toxicity were observed. Older patients (>median) or patients with V60 higher than 35% had significantly higher rates of grade ≥2 acute GI toxicity compared with the younger ones.
  
  
  CONCLUSIONS
  RapidArc in the treatment of localized prostate cancer is tolerated well with no Grade >3 GI and GU toxicities. Older patients or patients with higher V60 had significantly higher rates of grade ≥2 acute GI toxicity. Further research is necessary to assess definitive late toxicity and tumour control outcome.
authors: Department of Radiation Oncology, Hope International Radiotherapy Center, Guatemala City, Guatemala.
authors: Rafael E
authors: RE
authors: Lengua
authors: Department of Radiation Oncology, Hope International Radiotherapy Center, Guatemala City, Guatemala.
authors: Maria F
authors: MF
authors: Gonzalez
authors: Department of Radiation Oncology, Hope International Radiotherapy Center, Guatemala City, Guatemala.
authors: Kaory
authors: K
authors: Barahona
authors: Department of Radiation Oncology, Hope International Radiotherapy Center, Guatemala City, Guatemala.
authors: Milton E
authors: ME
authors: Ixquiac
authors: Department of Radiation Oncology, Hope International Radiotherapy Center, Guatemala City, Guatemala.
authors: Juan F
authors: JF
authors: Lucero
authors: Department of Radiation Oncology, Hope International Radiotherapy Center, Guatemala City, Guatemala.
authors: Erick
authors: E
authors: Montenegro
authors: Department of Radiation Oncology, Virgen del Rocío University Hospital, Seville, Spain.
authors: Jose L
authors: JL
authors: Lopez Guerra
authors: Department of Radiation Oncology, Instituto Oncológico Cartuja-Grupo IMO, Seville, Spain.
authors: Javier
authors: J
authors: Jaén
authors: Department of Radiation Oncology, Hope International Radiotherapy Center, Guatemala City, Guatemala.
authors: Luis A
authors: LA
authors: Linares
keywords: Arc therapy; Prostate cancer; RapidArc; Toxicity