OBJECTIVE: To elucidate the role of PSA doubling time (PSAdt) as a progression criterion in patients with low-risk prostate cancer managed on active surveillance (AS).
PSAdt was calculated with 95% confidence intervals (95% CI) in order to assess the risk of misclassification. Further, the correlation between PSAdt during AS and final histopathology following radical prostatectomy (RP) in patients meeting predefined progression criteria was evaluated.
PATIENTS AND METHODS: 258 consecutive patients followed in an AS program. PSAdt was calculated in patients with ≥2 PSA values, 95%CI was calculated in patients with ≥4 PSA values. Risk for progression was classified as: High-risk: PSAdt < 3 years, re-biopsy Gleason score ≥4+3, >3 positive biopsy cores, and/or bilateral tumour, or cT≥2c, intermediate-risk: PSAdt 3≤ 5 years, Gleason score=3+4 or cT2b, or low-risk: PSAdt >5 years and without histopathological or clinical progression. Definitive treatment was recommended high-risk patients and treatment options were discussed with intermediate-risk patients.
RESULTS: A total of 2.291 PSA determinations obtained during AS were available of which 2.071 were considered valid in the 258 patients. PSAdt with 95% CI was calculated in 221 patients based on a median of 8 PSA values. The 95% CIs for PSAdt overlapped considerably and up to 91% of the patients' 95% CI crossed between the risk-group definitions. In total 26% (68/258) underwent RP after meeting the progression criteria. There was no association between preoperative PSAdt and final histopathology (P = 0.87).
CONCLUSION: The uncertainty of calculated PSAdt during AS results in a significant risk of patients being misclassified according to the progression risk definitions which subsequent limits its use in the management of patients on AS.
Written by:
Thomsen FB, Christensen IJ, Brasso K, Røder MA, Iversen P. Are you the author?
Copenhagen Prostate Cancer Center, Department of Urology, Rigshospitalet; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen.
Reference: BJU Int. 2013 Jul 19. Epub ahead of print.
doi: 10.1111/bju.12367
PubMed Abstract
PMID: 24053601
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