Etzioni Ruth, Gulati Roman, Falcon Seth, Penson David F
Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1024, USA.
Med Decis Making. 2008 May-Jun;28(3):323-31. doi: 10.1177/0272989X07312719. Epub 2008 Mar 4.
and objective. Both the detection and the treatment of prostate cancer have undergone important clinical advances. Simultaneously, both distant stage incidence and disease-specific mortality have fallen in the United States. A recent study suggests that if prostate-specific antigen (PSA) testing explains the decline in distant stage incidence, then it may be largely responsible for the decline in mortality. The objective was to quantify this link between PSA screening and the decline in distant stage incidence.
A fixed-cohort simulation model of prostate cancer progression and screening was adapted to a population-based model that integrates new data on trends in testing and biopsy practices. The model was calibrated to pre-PSA incidence and then screening was superimposed, obtaining incidence projections in the absence and presence of testing. This approach permits calculation of clinically relevant measures for model validation and direct assessment of the role of testing in the distant stage incidence decline.
The model validated well with prior studies of natural history, and the sensitivity analysis indicated that the findings were robust to variation in model parameters. Model results indicate that PSA screening accounts for approximately 80% of the observed decline in distant stage incidence.
PSA screening contributed to the observed declines in distant stage incidence and mortality in the 1990s. However, additional factors, such as increasing awareness of prostate cancer and advances in treatment, have probably also played a role in these trends.
背景与目的。前列腺癌的检测与治疗均取得了重要的临床进展。与此同时，美国远处转移期发病率和疾病特异性死亡率均有所下降。最近一项研究表明，如果前列腺特异性抗原（PSA）检测能够解释远处转移期发病率的下降，那么它可能在很大程度上导致了死亡率的下降。目的是量化PSA筛查与远处转移期发病率下降之间的这种联系。
将前列腺癌进展与筛查的固定队列模拟模型调整为基于人群的模型，该模型整合了检测和活检实践趋势的新数据。该模型根据PSA检测前的发病率进行校准，然后叠加筛查，得出在有无检测情况下的发病率预测。这种方法允许计算用于模型验证的临床相关指标，并直接评估检测在远处转移期发病率下降中的作用。
该模型与先前关于自然病史的研究验证良好，敏感性分析表明研究结果对模型参数的变化具有稳健性。模型结果表明，PSA筛查约占观察到的远处转移期发病率下降的80%。
PSA筛查促成了20世纪90年代观察到的远处转移期发病率和死亡率的下降。然而，其他因素，如对前列腺癌认识的提高和治疗的进展，可能也在这些趋势中发挥了作用。
