title: Creation of 3-dimensional prostate cancer maps: methodology and clinical and research implications.
abstract: BACKGROUND
  The creation of 3-dimensional prostate cancer maps could assist with surgical intervention, radiotherapy treatment planning and for correlative pathology-imaging research.
  
  
  OBJECTIVE
  To develop methodology for creating detailed, 3-dimensional, prostate cancer maps (3DPCM) of tumor location, extra prostatic extension sites, and positive margins and to assess the adequacy of current clinical target volumes for postoperative radiotherapy to the prostate using 3DPCM coregistered with preoperative magnetic resonance imaging.
  
  
  METHODS
  Parallel slices of prostatectomy specimens were created with ProCUT, and 2-dimensional cancer maps were generated as line diagrams after microscopic examination of each slice. The 2-dimensional cancer maps were aligned and stacked to create a 3DPCM, which was coregistered with the preoperative magnetic resonance imaging scan. The map was exported to the radiotherapy planning system and was used to determine the areas at greater risk, which were then compared against the current Radiation Therapy Oncology Group guidelines for contouring postoperative clinical target volumes to assess the adequacy of coverage.
  
  
  RESULTS
  Twenty-eight patients with a mean age of 66 years (range, 52-73) underwent radical prostatectomy and postoperative radiotherapy. Seventeen patients (61%) received adjuvant radiotherapy for pT3 disease and/or positive margins, and the rest underwent salvage radiotherapy. Thirty-nine percent (11 of 28) of the patients had Gleason scores of 8 or 9. The contours based on the Radiation Therapy Oncology Group guidelines for postoperative radiotherapy resulted in inadequate coverage of extraprostatic extensions in 79% (22 of 28) and positive margins in 64% (18 of 28) of the cases.
  
  
  CONCLUSIONS
  We have developed a methodology for creation of 3DPCM. Modification of the radiotherapy contours, based on the 3DPCM coregistered with pretreatment magnetic resonance imaging, covers the areas at high risk of recurrence. The 3DPCM could become an important clinical and research tool for urologists, pathologists, radiologists, and oncologists.
authors.affiliation: From the Divisions of Radiation Oncology (Drs S. C. Malone, Haridass, Croke, and C. Malone, and Mr K. Malone) and Urology (Drs Breau and Morash) and the Departments of Medical Physics (Dr Nyiri), Radiology, (Dr Avruch), and Pathology (Drs Daneshmand, Ahmed, and Belanger), Ottawa Hospital, Ottawa, Ontario, Canada; and the Department of Medical Biology, Montfort Hospital, Ottawa, Ontario, Canada (Dr Delatour).
authors.forename: Shawn Christopher
authors.initials: SC
authors.lastname: Malone
authors.forename: Anoop
authors.initials: A
authors.lastname: Haridass
authors.forename: Balasz
authors.initials: B
authors.lastname: Nyiri
authors.forename: Jennifer
authors.initials: J
authors.lastname: Croke
authors.forename: Colin
authors.initials: C
authors.lastname: Malone
authors.forename: Rodney H
authors.initials: RH
authors.lastname: Breau
authors.forename: Christopher
authors.initials: C
authors.lastname: Morash
authors.forename: Leonard
authors.initials: L
authors.lastname: Avruch
authors.forename: Manijeh
authors.initials: M
authors.lastname: Daneshmand
authors.forename: Kyle
authors.initials: K
authors.lastname: Malone
authors.forename: Nicolas Roustan
authors.initials: NR
authors.lastname: Delatour
authors.forename: Ileyaz
authors.initials: I
authors.lastname: Ahmed
authors.forename: Eric
authors.initials: E
authors.lastname: Belanger
mesh_terms: D000368:Aged; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000473:pathology* / Q000532:radiotherapy / Q000601:surgery; D011880:Radiotherapy Planning, Computer-Assisted