title: The independent value of tumour volume in a contemporary cohort of men treated with radical prostatectomy for clinically localized disease.
abstract: OBJECTIVE
  To determine if prostate tumour volume is an independent prognostic factor in a contemporary cohort of men who had a radical prostatectomy (RP) for clinically localized disease, as the effect of tumour volume on prostate cancer outcomes has not been consistently shown in the era of widespread screening with prostate-specific antigen (PSA).
  
  
  METHODS
  The study included 856 men who had RP from 1998 to 2007 for localized prostate cancer. Tumour volume based on pathology was analysed as a continuous and categorized (<0.26, 0.26-0.50, 0.51-1.00, 1.01-2.00, 2.01-4.00, >4.00 mL) variable using Cox proportional hazards regression and Kaplan-Meier analysis. A multivariable analysis was also conducted controlling for PSA level, Gleason grade, surgical margins, and pathological stage.
  
  
  RESULTS
  Tumour volume had a positive association with grade and stage, but did not correlate with biochemical recurrence-free survival on univariate analysis as a continuous variable (hazard ratio 1.00, P = 0.09), and was only statistically significant for volumes of >4 mL as a categorical variable. No tumour volume was an independent predictor of prostate cancer recurrence on multivariate analysis. There was no difference between tumour volume and time to cancer recurrence for organ-confined tumours using Kaplan-Meier analysis. In low-risk patients (PSA level <10 ng/mL, Gleason score < or = 6, clinical stage T1c/T2a) tumour volume did not correlate with biochemical recurrence-free survival in univariate or multivariable analysis.
  
  
  CONCLUSIONS
  There is no evidence that tumour volume is an independent predictor of prostate cancer outcome and it should not be considered as a marker of tumour risk, behaviour or prognosis.
authors.affiliation: Department of Urology, University of California, San Francisco, USA. sporten@urology.ucsf.edu
authors.forename: Sima P
authors.initials: SP
authors.lastname: Porten
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Cooperberg
authors.forename: Peter R
authors.initials: PR
authors.lastname: Carroll
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018572:Disease-Free Survival; D004812:Epidemiologic Methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology*; D009367:Neoplasm Staging; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood; D011468:Prostatectomy / Q000379:methods*; D011471:Prostatic Neoplasms / Q000473:pathology* / Q000601:surgery; D047368:Tumor Burden
chemical_list: D017430:Prostate-Specific Antigen
references.citation: Urology. 2007 Aug;70(2):294-8
references.pmid: 17826492
references.citation: Urol Clin North Am. 1997 May;24(2):395-406
references.pmid: 9126237
references.citation: Mod Pathol. 2005 Jul;18(7):886-90
references.pmid: 15803186
references.citation: Int J Urol. 1999 May;6(5):240-4
references.pmid: 10375186
references.citation: World J Urol. 2008 Jun;26(3):237-41
references.pmid: 18265988
references.citation: J Clin Oncol. 1999 May;17(5):1499-507
references.pmid: 10334537
references.citation: Am J Clin Pathol. 1997 Jun;107(6):704-8
references.pmid: 9169669
references.citation: J Urol. 2003 Dec;170(6 Pt 2):S21-5; discussion S26-7
references.pmid: 14610406
references.citation: BJU Int. 2006 Jun;97(6):1169-72
references.pmid: 16686706
references.citation: J Cell Biochem. 2004 Jan 1;91(1):125-50
references.pmid: 14689586
references.citation: J Urol. 1998 Dec;160(6 Pt 1):2096-101
references.pmid: 9817331
references.citation: J Urol. 1997 Jun;157(6):2212-8
references.pmid: 9146618
references.citation: Br J Cancer. 2003 Jan 27;88(2):195-201
references.pmid: 12610502
references.citation: Eur Urol. 2003 Jan;43(1):39-44
references.pmid: 12507542
references.citation: J Urol. 2003 Nov;170(5):1792-7
references.pmid: 14532778
references.citation: J Urol. 1993 Jun;149(6):1478-81
references.pmid: 8501792
references.citation: J Urol. 2004 Aug;172(2):508-11
references.pmid: 15247716
references.citation: Cancer. 1993 Feb 1;71(3 Suppl):933-8
references.pmid: 7679045
references.citation: JAMA. 1999 Apr 21;281(15):1395-400
references.pmid: 10217055