Accuracy of life tables in predicting overall survival in patients after radical prostatectomy

Cancer Prognostics and Health Outcomes Unit, University of Montreal Health Center, Montreal, Quebec, Canada.
BJU International (Impact Factor: 3.53). 08/2008; 102(1):33-8. DOI: 10.1111/j.1464-410X.2008.07614.x
Source: PubMed


To test the accuracy of life tables (LT), the standard tool for predicting life-expectancy (LE), but the accuracy of which is unknown in patients with prostate cancer, where the 10-year LE is a widely accepted threshold for the delivery of definitive therapy.
We tested the accuracy of predictions of LE from LT in 9678 men treated with radical prostatectomy (RP) for prostate cancer. The predictions of LE from LT at 10 years after RP were compared to Kaplan Meier-derived 10-year survival values. Moreover, the accuracy of LT predictions was quantified in a Cox-regression using Harrell's concordance index. To control for the effect of prostate cancer mortality, analyses were repeated in a subset of 5955 patients with no evidence of disease recurrence. Additional stratification schemes were applied to control for age and comorbidity.
At RP, the median age was 64 years, the median Charlson Comorbidity Index (CCI) was 1 and the median LT-derived LE was 16 years. The median actuarial survival was not reached (mean 12.4 years). In the whole group the LT-predicted 10-year survival was 96.8%, vs an observed of 75.3%. In men with no disease recurrence the LT-predicted survival was 97.3%, vs 81.1% observed. After age and CCI stratification, LT overestimated the 10-year survival the most in those aged 65-69 years and in patients with CCI scores of >2.
The overestimation of LE can lead to overtreatment of prostate cancer, especially in those men who die early from other causes.

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    • "To date, no systematic classification of SM rates has been proposed. For example, there is no system that stratifies SM rates according to age, gender, or disease stage [11] [12]. Moreover, there are no data examining the contemporary trends of SM after nephrectomy. "
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    ABSTRACT: The existing literature suggests that the surgical mortality (SM) observed with nephrectomy for localised disease varies from 0.6% to 3.6%. To examine age- and stage-specific 30-d mortality (TDM) rates after partial or radical nephrectomy. We relied on 24535 assessable patients from the National Cancer Institute (NCI) Surveillance, Epidemiology, and End Results (SEER) database. In 12283 patients, logistic regression models were used to develop a tool for pretreatment prediction of the probability of TDM according to individual patient and tumour characteristics. External validation was performed on 12252 patients. In the entire cohort of 24535 patients, 219 deaths occurred during the initial 30 d after nephrectomy (0.9% TDM rate). TDM increased with age (≤49 yr: 0.5% vs 50-59 yr: 0.7% vs 60-69 yr: 0.9% vs 70-79 yr: 1.2% vs ≥80 yr: 2.0%; χ(2) trend p<0.001) and stage (0.3% for T1-2N0M0 vs 1.3% for T3-4N0-2M0 vs 4.2% for T1-4N0-2M1; χ2 trend p=<0.001). TDM decreased in more recent years (1988-1993: 1.3% vs 1994-1998: 0.9% vs 1999-2002: 0.7% vs 2003-2004: 0.6%; χ2 trend p<0.001) and was lower after partial versus radical nephrectomy (RN) (0.4% vs 0.9%; p=0.008). Only age (p<0.001) and stage (p<0.001) achieved independent predictor status. The look-up table that relied on the regression coefficients of age and stage reached 79.4% accuracy in the external validation cohort. Age and stage are the foremost determinants of TDM after nephrectomy. Our model provides individual probabilities of TDM after nephrectomy, and its use should be highly encouraged during informed consent prior to planned nephrectomy.
    Full-text · Article · Dec 2008 · European Urology
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    • "To date, no systematic classification of SM rates has been proposed. For example, there is no system that stratifies SM rates according to age, gender, or disease stage [11] [12]. Moreover, there are no data examining the contemporary trends of SM after nephrectomy. "

    Full-text · Article · Dec 2008 · European Urology
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    ABSTRACT: Prostate cancer is the second leading cause of cancer deaths among men. Despite earlier diagnosis due to prostate specific antigen (PSA) screening, it is still a disease of the elderly. Diagnosis is based on digital rectal examination (DRE) and PSA assessment. Refinements in PSA testing (age-specific reference ranges, free PSA, PSA density and velocity) increased specificity and limited unnecessary prostate biopsies. Diagnosis in earlier stages (T1 and T2) commonly leads to cure with current treatment modalities. These include radical prostatectomy, external beam radiotherapy and brachytherapy. Other treatment options under development include cryotherapy and high-intensity focused ultrasound. Metastatic prostate cancer is incurable and treatment is based on hormonal therapy. Cytotoxic chemotherapy has only limited role in hormone-independent prostate cancer. Radioisotopes and biphosphonates may alleviate bone pain and prevent osteoporosis and pathological fractures. Follow-up is based on PSA. Prognostic factors for recurrence include stage, Gleason score, pre- and posttreatment PSA. Quality of life issues play an important role in selecting treatment, especially in the elderly due to comorbidities that may negatively affect the overall quality of life. A holistic approach is recommended addressing all quality of life issues without focus only in cancer control.
    No preview · Article · Feb 2005 · International Urology and Nephrology
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