title: Intensity-Modulated Radiation Therapy with Stereotactic Body Radiation Therapy Boost for Unfavorable Prostate Cancer: The Georgetown University Experience.
abstract: OBJECTIVE
  Stereotactic body radiation therapy (SBRT) is emerging as a minimally invasive alternative to brachytherapy to deliver highly conformal, dose--escalated radiation therapy (RT) to the prostate. SBRT alone may not adequately cover the tumor extensions outside the prostate commonly seen in unfavorable prostate cancer. External beam radiation therapy (EBRT) with high dose rate brachytherapy boost is a proven effective therapy for unfavorable prostate cancer. This study reports on early prostate-specific antigen and prostate cancer-specific quality of life (QOL) outcomes in a cohort of unfavorable patients treated with intensity-modulated radiation therapy (IMRT) and SBRT boost.
  
  
  METHODS
  Prostate cancer patients treated with SBRT (19.5 Gy in three fractions) followed by fiducial-guided IMRT (45-50.4 Gy) from March 2008 to September 2012 were included in this retrospective review of prospectively collected data. Biochemical failure was assessed using the Phoenix definition. Patients completed the expanded prostate cancer index composite (EPIC)-26 at baseline, 1 month after the completion of RT, every 3 months for the first year, then every 6 months for a minimum of 2 years.
  
  
  RESULTS
  One hundred eight patients (4 low-, 45 intermediate-, and 59 high-risk) with median age of 74 years completed treatment, with median follow-up of 4.4 years. Sixty-four percent of the patients received androgen deprivation therapy prior to the initiation of RT. The 3-year actuarial biochemical control rates were 100 and 89.8% for intermediate- and high-risk patients, respectively. At the initiation of RT, 9 and 5% of men felt their urinary and bowel function was a moderate to big problem, respectively. Mean EPIC urinary and bowel function and bother scores exhibited transient declines, with subsequent return to near baseline. At 2 years posttreatment, 13.7 and 5% of men felt their urinary and bowel function was a moderate to big problem, respectively.
  
  
  CONCLUSIONS
  At 3-year follow-up, biochemical control was favorable. Acute urinary and bowel symptoms were comparable to conventionally fractionated IMRT and brachytherapy. Patients recovered to near their baseline urinary and bowel function by 2 years posttreatment. A combination of IMRT with SBRT boost is well tolerated with minimal impact on prostate cancer-specific QOL.
authors.affiliation: Department of Radiation Medicine, Georgetown University Hospital , Washington, DC , USA.
authors.forename: Catherine
authors.initials: C
authors.lastname: Mercado
authors.affiliation: Department of Radiation Medicine, Georgetown University Hospital , Washington, DC , USA.
authors.forename: Marie-Adele
authors.initials: MA
authors.lastname: Kress
authors.affiliation: Department of Radiation Medicine, Georgetown University Hospital , Washington, DC , USA.
authors.forename: Robyn A
authors.initials: RA
authors.lastname: Cyr
authors.affiliation: Department of Radiation Medicine, Georgetown University Hospital , Washington, DC , USA.
authors.forename: Leonard N
authors.initials: LN
authors.lastname: Chen
authors.affiliation: Department of Radiation Medicine, Georgetown University Hospital , Washington, DC , USA.
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Yung
authors.affiliation: Department of Radiation Medicine, Georgetown University Hospital , Washington, DC , USA.
authors.forename: Elizabeth G
authors.initials: EG
authors.lastname: Bullock
authors.affiliation: Department of Radiation Medicine, Georgetown University Hospital , Washington, DC , USA.
authors.forename: Siyuan
authors.initials: S
authors.lastname: Lei
authors.affiliation: Department of Radiation Medicine, Georgetown University Hospital , Washington, DC , USA.
authors.forename: Brian T
authors.initials: BT
authors.lastname: Collins
authors.affiliation: Department of Radiation Medicine, Georgetown University Hospital , Washington, DC , USA.
authors.forename: Andrew N
authors.initials: AN
authors.lastname: Satinsky
authors.affiliation: Department of Radiation Medicine, Georgetown University Hospital , Washington, DC , USA.
authors.forename: K William
authors.initials: KW
authors.lastname: Harter
authors.affiliation: Department of Radiation Medicine, Georgetown University Hospital , Washington, DC , USA.
authors.forename: Simeng
authors.initials: S
authors.lastname: Suy
authors.affiliation: Department of Radiation Medicine, Georgetown University Hospital , Washington, DC , USA.
authors.forename: Anatoly
authors.initials: A
authors.lastname: Dritschilo
authors.affiliation: Department of Urology, Georgetown University Hospital , Washington, DC , USA.
authors.forename: John H
authors.initials: JH
authors.lastname: Lynch
authors.affiliation: Department of Radiation Medicine, Georgetown University Hospital , Washington, DC , USA.
authors.forename: Sean P
authors.initials: SP
authors.lastname: Collins
keywords: CyberKnife; EPIC; IGRT; IMRT; SBRT; prostate cancer