Objectives:To analyze the association between prostate-specific antigen doubling time with prostate cancer risk and grade among men with prostate-specific antigen levels ≥4.0 ng/mL undergoing repeat prostate biopsy.
Methods: A total of 286 patients with prostate-specific antigen ≥4 ng/mL and available prostate-specific antigen doubling time data, who underwent repeat prostate biopsy from 1996-2009, were included in this analysis. Prostate-specific antigen doubling time was divided into three groups: >9 years, 3-9 years and < 3 years. Multivariate analyses of prostate-specific antigen doubling time with cancer risk and grade (≤ 3 + 4 vs≥4 + 3) were carried out using logistic regression adjusting for prebiopsy prostate-specific antigen, race, age, digital rectal examination, year of biopsy and number of prior negative biopsies.
Results: The median prostate-specific antigen doubling time before biopsy was 4.5 years (interquartile range = 2.5-10). Shorter prostate-specific antigen doubling time was associated with higher prostate-specific antigen (P < 0.001), but it was unrelated to age, digital rectal examination or race. Shorter prostate-specific antigen doubling time as a continuous variable was associated with greater prostate cancer risk in both uni- (hazard ratio = 0.99, 95% confidence interval = 0.98-0.99, P = 0.001) and multivariate analysis (hazard ratio = 0.99, 95% confidence interval = 0.98-0.99, P = 0.004). The prevalence of cancer among prostate-specific antigen doubling time groups (>9, 3-9, < 3 years) was 17%, 37% and 40%, respectively. Shorter prostate-specific antigen doubling time groups were associated with higher cancer risk (P = 0.001). Stratified by grade, short prostate-specific antigen doubling time as a continuous variable significantly predicted both low- (P = 0.010) and high-grade disease (P = 0.049). The inclusion of prostate-specific antigen doubling time groups in a multivariate model to predict biopsy positivity increased its accuracy from 0.69 to 0.74.
Conclusion: Prostate-specific antigen doubling time seems to provide further cancer risk assessment in men undergoing repeat biopsy for prostate-specific antigen ≥4.0 ng/mL. If validated in future studies, the present findings support the use of prostate-specific antigen doubling time in the risk stratification of this patient population.
Written by:
Moreira DM, Gerber L, Thomas JA, Bañez LL, McKeever MG, Freedland SJ. Are you the author?
Division of Urologic Surgery, Department of Surgery, Duke Prostate Center Department of Pathology, Duke University School of Medicine Urology Section, Veterans Affairs Medical Center, Durham, North Carolina, USA.
Reference: Int J Urol. 2012 Apr 4. Epub ahead of print.
doi: 10.1111/j.1442-2042.2012.03016.x
PubMed Abstract
PMID: 22487442
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