Contemporary evaluation of the D'Amico risk classification of prostate cancer
ABSTRACT In 1998, D'Amico et al. suggested a model stratifying patients with prostate cancer into those with low, intermediate, or high-risk of biochemical recurrence after surgery according to the clinical TNM stage, biopsy Gleason score, and preoperative prostate-specific antigen level. We studied the performance and clinical relevance of this classification system over time, in the context of the stage migration seen in the contemporary era, using data from a high-volume, tertiary referral center.
From 1984 to 2005, 6652 men underwent radical prostatectomy at our institution for clinically localized prostate cancer (clinical Stage T1c-T2c) with follow-up information available and no neoadjuvant or adjuvant therapy before biochemical recurrence. Biochemical recurrence-free survival (BRFS) was estimated using the Kaplan-Meier method, and the BRFS rates between the D'Amico risk groups and by era were compared using the log-rank statistic. Finally, the distribution of patients among the three groups was compared over time.
The 5-year BRFS rate was 84.6% overall and 94.5%, 76.6%, and 54.6% for the low, intermediate, and high-risk groups, respectively (P <0.0001). In the contemporary era, a very small fraction (4.9%) of patients undergoing radical prostatectomy at our institution were in the high-risk group, with most (67.7%) in the low-risk group (P <0.001).
The D'Amico classification system continues to stratify men into risk groups with statistically significant differences in BRFS. However, the major shift in the distribution of patients among the three risk groups over time suggests that the clinical relevance of this classification scheme may be limited and diminishing in the contemporary era.
- SourceAvailable from: Stacy LoebExpert Review of Endocrinology & Metabolism 01/2014; 5(6). DOI:10.1586/eem.10.64
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ABSTRACT: Objective To investigate the post-prostatectomy and long-term outcomes of men presenting with an elevated pretreatment prostate-specific antigen (PSA) level (>10ng/mL), but otherwise low-risk features (biopsy Gleason score 6 and clinical stage T2a). Patients and MethodsPSA-incongruent intermediate-risk (PII) cases were defined as those patients with preoperative PSA >10 and 20ng/mL but otherwise low-risk features, and PSA-incongruent high-risk (PIH) cases were defined as men with PSA >20ng/mL but otherwise low-risk features. Our institutional radical prostatectomy database (1992-2012) was queried and the results were stratified into D'Amico low-, intermediate- and high risk, PSA-incongruent intermediate-risk and PSA-incongruent high-risk cases. Prostate cancer (PCa) features and outcomes were evaluated using appropriate comparative tests. Multivariable analyses were adjusted for age, race and year of surgery. ResultsOf the total cohort of 17 608 men, 1132 (6.4%) had PII-risk disease and 183 (1.0%) had PIH-risk disease. Compared with the low-risk group, the odds of upgrading at radical prostatectomy (RP) were 2.20 (95% CI 1.93-2.52; P < 0.001) for the PII group and 3.58 (95% CI 2.64-4.85; P < 0.001) for the PIH group, the odds of extraprostatic disease at RP were 2.35 (95% CI 2.05-2.68; P < 0.001) for the PII group and 6.68 (95% CI 4.89-9.15; P < 0.001) for the PIH group, and the odds of positive surgical margins were 1.97 (95% CI 1.67-2.33; P < 0.001) for the PII group and 3.54 (95% CI 2.50-4.95, P < 0.001) for the PIH group. Compared with low-risk disease, PII-risk disease was associated with a 2.85-, 2.99- and 3.32-fold greater risk of biochemical recurrence (BCR), metastasis and PCa-specific mortality, respectively, and PIH-risk disease was associated with a 5.32-, 6.14- and 7.07-fold greater risk of BCR, metastasis and PCa-specific mortality, respectively (P 0.001 for all comparisons). For the PII group, the higher risks of positive surgical margins, upgrading, upstaging and BCR were dependent on PSA density (PSAD): men in the PII group who had a PSAD <0.15ng/mL/g were not at higher risk compared with those in the low-risk group. Men in the PII group with a PSAD 0.15ng/mL/g and men in the PIH group were more likely to have an anterior component of the dominant tumour (59 and 64%, respectively) compared with those in the low- (35%) and intermediate-risk group (39%) and those in the PII-risk group with PSAD <0.15ng/mL/g (29%). Conclusions Men with PSA >20ng/mL or men with PSA >10 and 20ng/mL with a PSAD 0.15ng/mL/g, but otherwise low-risk PCa, are at greater risk of adverse pathological and oncological outcomes and may be inappropriate candidates for active surveillance. These men are at greater risk of having anterior tumours that are undersampled at biopsy, so if treatment is deferred, ancillary testing such as anterior zone sampling or magnetic resonance imaging should be strongly encouraged. Men with elevated PSA levels >10 and 20ng/mL but low PSAD have outcomes similar to those in the low-risk group, and consideration of surveillance is appropriate in these cases.BJU International 04/2014; 114(6B). DOI:10.1111/bju.12771 · 3.13 Impact Factor
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ABSTRACT: Objective To determine whether the currently available pretreatment risk classification systems are applicable in Japanese prostate cancer patients.Methods Using data obtained from 1264 consecutive patients with prostate cancer treated with radical prostatectomy at four hospitals in Japan, biochemical recurrence-free survival rates were estimated and compared between the D'Amico, the National Institute for Health and Clinical Excellence, the Cancer of the Prostate Strategic Urological Research Endeavor, the National Comprehensive Cancer Network, and the European Society of Medical Oncology risk groups by using the Kaplan–Meier method and log–rank test.ResultsThe 5-year biochemical recurrence-free survival rates in the D'Amico low-, intermediate-, and high-risk groups were 88.3%, 84.7% and 66.9%, respectively (low and intermediate risk vs high risk, P < 0.001). The 5-year biochemical recurrence-free survival rates in the National Institute for Health and Clinical Excellence, National Comprehensive Cancer Network, and European Society of Medical Oncology low-, intermediate- and high-risk groups were 88.3%, 84.3%, and 60.3%, respectively (low and intermediate risk vs high risk, P < 0.001). The 5-year biochemical recurrence-free survival rates in the Cancer of the Prostate Strategic Urological Research Endeavor low-, intermediate-, and high-risk groups were 90%, 83.5% and 60.3%, respectively (low and intermediate risk vs high risk, P < 0.001). Low- and intermediate-risk groups according to any of the risk stratification systems did not show significant differences in biochemical recurrence-free survival.Conclusion Current risk stratification systems do not discriminate between low- and intermediate-risk groups in the Japanese population. A novel, pretreatment risk stratification system including other prognostic factors is necessary for an adequate prostate cancer risk assessment in the Japanese population.International Journal of Urology 09/2014; 22(1). DOI:10.1111/iju.12597 · 1.80 Impact Factor