title: Robot-assisted radical prostatectomy: Multiparametric MR imaging-directed intraoperative frozen-section analysis to reduce the rate of positive surgical margins.
abstract: OBJECTIVE
  To investigate whether use of multiparametric magnetic resonance (MR) imaging-directed intraoperative frozen-section (IFS) analysis during nerve-sparing robot-assisted radical prostatectomy reduces the rate of positive surgical margins.
  
  
  METHODS
  This retrospective analysis of prospectively acquired data was approved by an institutional ethics committee, and the requirement for informed consent was waived. Data were reviewed for 134 patients who underwent preoperative multiparametric MR imaging (T2 weighted, diffusion weighted, and dynamic contrast-material enhanced) and nerve-sparing robot-assisted radical prostatectomy, during which IFS analysis was used, and secondary resections were performed when IFS results were positive for cancer. Control patients (n = 134) matched for age, prostate-specific antigen level, and stage were selected from a pool of 322 patients who underwent nerve-sparing robot-assisted radical prostatectomy without multiparametric MR imaging and IFS analysis. Rates of positive surgical margins were compared by means of the McNemar test, and a multivariate conditional logistic regression model was used to estimate the odds ratio of positive surgical margins for patients who underwent MR imaging and IFS analysis compared with control subjects.
  
  
  RESULTS
  Eighteen patients who underwent MR imaging and IFS analysis underwent secondary resections, and 13 of these patients were found to have negative surgical margins at final pathologic examination. Positive surgical margins were found less frequently in the patients who underwent MR imaging and IFS analysis than in control patients (7.5% vs 18.7%, P = .01). When the differences in risk factors are taken into account, patients who underwent MR imaging and IFS had one-seventh the risk of having positive surgical margins relative to control patients (adjusted odds ratio: 0.15; 95% confidence interval: 0.04, 0.61).
  
  
  CONCLUSIONS
  The significantly lower rate of positive surgical margins compared with that in control patients provides preliminary evidence of the positive clinical effect of multiparametric MR imaging-directed IFS analysis for patients who undergo prostatectomy.
authors.affiliation: From the Divisions of Radiology (G.P., P.S., S.A., M.B.), Urology (G.M., D.V.M., O.D.C.), Pathology (G.R., S.L.R.), Epidemiology and Biostatistics (S.R.), and Radiotherapy (B.A.J.F.), European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy; Paul Strickland Scanner Centre, Mount Vernon Cancer Centre, Middlesex, England (A.R.P.); and Department of Health Sciences, University of Milan, Milan, Italy (S.L.R., B.A.J.F., O.D.C., M.B.).
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Petralia
authors.forename: Gennaro
authors.initials: G
authors.lastname: Musi
authors.forename: Anwar R
authors.initials: AR
authors.lastname: Padhani
authors.forename: Paul
authors.initials: P
authors.lastname: Summers
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Renne
authors.forename: Sarah
authors.initials: S
authors.lastname: Alessi
authors.forename: Sara
authors.initials: S
authors.lastname: Raimondi
authors.forename: Deliu V
authors.initials: DV
authors.lastname: Matei
authors.forename: Salvatore L
authors.initials: SL
authors.lastname: Renne
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Jereczek-Fossa
authors.forename: Ottavio
authors.initials: O
authors.lastname: De Cobelli
authors.forename: Massimo
authors.initials: M
authors.lastname: Bellomi
mesh_terms: D000368:Aged; D005629:Frozen Sections; D006801:Humans; D007430:Intraoperative Care; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011468:Prostatectomy / Q000379:methods*; D011471:Prostatic Neoplasms / Q000473:pathology* / Q000601:surgery*; D012189:Retrospective Studies; D065287:Robotic Surgical Procedures / Q000379:methods*; D025321:Surgery, Computer-Assisted