title: Boosting imaging defined dominant prostatic tumors: a systematic review.
abstract: BACKGROUND
  Dominant cancer foci within the prostate are associated with sites of local recurrence post radiotherapy. In this systematic review we sought to address the question: "what is the clinical evidence to support differential boosting to an imaging defined GTV volume within the prostate when delivered by external beam or brachytherapy".
  
  
  METHODS
  A systematic review was conducted to identify clinical series reporting the use of radiation boosts to imaging defined GTVs.
  
  
  RESULTS
  Thirteen papers describing 11 unique patient series and 833 patients in total were identified. Methods and details of GTV definition and treatment varied substantially between series. GTV boosts were on average 8 Gy (range 3-35 Gy) for external beam, or 150% for brachytherapy (range 130-155%) and GTV volumes were small (<10 ml). Reported toxicity rates were low and may reflect the modest boost doses, small volumes and conservative DVH constraints employed in most studies. Variability in patient populations, study methodologies and outcomes reporting precluded conclusions regarding efficacy.
  
  
  CONCLUSIONS
  Despite a large cohort of patients treated differential boosts to imaging defined intra-prostatic targets, conclusions regarding optimal techniques and/or efficacy of this approach are elusive, and this approach cannot be considered standard of care. There is a need to build consensus and evidence. Ongoing prospective randomized trials are underway and will help to better define the role of differential prostate boosts based on imaging defined GTVs.
authors.affiliation: Department of Oncology, London Health Sciences Centre and University of Western Ontario and Western University, Canada. glenn.bauman@lhsc.on.ca
authors.forename: Glenn
authors.initials: G
authors.lastname: Bauman
authors.forename: Masoom
authors.initials: M
authors.lastname: Haider
authors.forename: Uulke A
authors.initials: UA
authors.lastname: Van der Heide
authors.forename: Cynthia
authors.initials: C
authors.lastname: Ménard
mesh_terms: D006801:Humans; D008297:Male; D049268:Positron-Emission Tomography; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D015899:Tomography, Emission-Computed, Single-Photon; D047368:Tumor Burden
keywords: Boost; DIL; GTV; MRI; PET; Prostate; SPECT