title: Reduced late urinary toxicity with high-dose intensity-modulated radiotherapy using intra-prostate fiducial markers for localized prostate cancer.
abstract: OBJECTIVE
  To evaluate the impact of intensity-modulated radiotherapy (IMRT) with intra-prostate fiducial markers image-guided radiotherapy (IGRT) on the incidence of late urinary toxicity compared to 3D conformal radiotherapy (3DCRT) for patients with prostate cancer (PC).
  
  
  METHODS
  We selected 733 consecutive patients with localized PC treated with dose-escalation radiotherapy between 2001 and 2014. Eligibility criteria were radiation dose >72.0 Gy, no pelvic RT and minimum follow-up 24 months. 438 patients were treated with 3DCRT and 295 with IMRT. Acute and late urinary complications were assessed using the EORTC/RTOG and CTCAEs v3.0 definition. The Cox regression model was used to compare grade ≥2 urinary toxicity between both techniques. The median follow-up was 75 months (range 24-204).
  
  
  RESULTS
  The median isocenter radiation dose was 78.7 Gy for 3DCRT and 80.7 Gy for IMRT/IGRT (p < 0.001). The 5-year incidence of late grade ≥2 urinary toxicity was 6.4% for IMRT and 10.8% for 3DCRT [hazard ratio (HR) 0.575, p = 0.056]. The corresponding 5-year estimates of late grade ≥2 hematuria were 2% for IMRT and 5.3% for 3DCRT (HR 0.296, p = 0.024). On multivariate analysis, the antecedent of prior transurethral resection of the prostate was also a strong predictor of a higher risk of urinary complications (HR 2.464, p = 0.002) and of hematuria (HR 5.196, p < 0.001).
  
  
  CONCLUSIONS
  Compared with 3DCRT, high-dose IMRT/IGRT is associated with a lower rate of late urinary complications in spite of higher radiation dose.
authors.affiliation: Department of Radiation Oncology, Hospital Universitario de La Princesa, Health Research Institute IIS-IP, Diego de León 62, 28006, Madrid, Spain. almudena.zapatero@salud.madrid.org.
authors.forename: A
authors.initials: A
authors.lastname: Zapatero
authors.affiliation: Department of Radiation Oncology, Hospital Universitario de La Princesa, Health Research Institute IIS-IP, Diego de León 62, 28006, Madrid, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Roch
authors.affiliation: Department of Radiation Oncology, Hospital Universitario de La Princesa, Health Research Institute IIS-IP, Diego de León 62, 28006, Madrid, Spain.
authors.forename: D
authors.initials: D
authors.lastname: Büchser
authors.affiliation: Department of Radiation Oncology, Hospital Universitario de La Princesa, Health Research Institute IIS-IP, Diego de León 62, 28006, Madrid, Spain.
authors.forename: P
authors.initials: P
authors.lastname: Castro
authors.affiliation: Department of Radiation Oncology, Hospital Universitario de La Princesa, Health Research Institute IIS-IP, Diego de León 62, 28006, Madrid, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Fernández-Banda
authors.affiliation: Department of Radiation Oncology, Hospital Universitario de La Princesa, Health Research Institute IIS-IP, Diego de León 62, 28006, Madrid, Spain.
authors.forename: G
authors.initials: G
authors.lastname: Pozo
authors.affiliation: Department of Radiation Oncology, Hospital Universitario de La Princesa, Health Research Institute IIS-IP, Diego de León 62, 28006, Madrid, Spain.
authors.forename: O
authors.initials: O
authors.lastname: Liñán
authors.affiliation: Department of Radiation Oncology, Hospital Universitario de La Princesa, Health Research Institute IIS-IP, Diego de León 62, 28006, Madrid, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Martin de Vidales
authors.affiliation: Department of Radiation Oncology, Hospital Universitario de La Princesa, Health Research Institute IIS-IP, Diego de León 62, 28006, Madrid, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Cruz-Conde
authors.affiliation: Department of Radiation Oncology, Hospital Universitario de La Princesa, Health Research Institute IIS-IP, Diego de León 62, 28006, Madrid, Spain.
authors.forename: F
authors.initials: F
authors.lastname: García-Vicente
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D057918:Fiducial Markers; D006801:Humans; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000517:prevention & control*; D061089:Radiotherapy, Image-Guided / Q000379:methods*; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects* / Q000379:methods; D012189:Retrospective Studies; D001743:Urinary Bladder / Q000528:radiation effects*
keywords: 3DCRT; Hematuria; IMRT; Late toxicity; Prostate cancer; Urinary toxicity