Any effective screening program must satisfy 2 criteria: 1) the test must identify clinically significant disease earlier than its clinical presentation, and 2) a treatment must be available that will alter the natural history of the disease. The controversy surrounding PSA testing that has raged since 1991 centers on these 2 points. Screening and treatment trials published during the past 3 decades have provided critical insights into our understanding of the natural history of PSA identified cancers and the impact of treatment. This in turn raises questions concerning the mechanism of prostate cancer mortality reduction. This essay reflects on the mechanisms of disease progression and the implications for future screening and treatment efforts.

任何有效的筛查程序都必须满足 2 个标准：1) 测试必须比临床表现更早地识别具有临床意义的疾病，以及 2) 必须提供可以改变疾病自然病程的治疗方法。自 1991 年以来围绕 PSA 测试的争论一直围绕着这两点展开。在过去 3 年中发表的筛查和治疗试验为我们了解 PSA 确定的癌症的自然史和治疗的影响提供了重要的见解。这反过来又引发了有关前列腺癌死亡率降低机制的问题。本文反映了疾病进展的机制以及对未来筛查和治疗工作的影响。