Littrup P J, Goodman A C
Department of Radiology, Harper Hospital, Detroit, MI 48201.
In Vivo. 1994 May-Jun;8(3):423-7.
Optimal combinations of digital rectal examination (DRE), transrectal ultrasound (TRUS) and prostate specific antigen (PSA) may better detect patients at high risks, as well as those in whom continued screening may not be cost effective. Our recent cost analysis of prostate cancer early detection used current data from three consecutive years of the American Cancer Society's National Prostate Cancer Detection Project. Marginal cost analysis showed marked increased costs for the DRE by year three due to significantly reduced sensitivity for incident cancers. The benefit-cost equation acknowledges that many parameters of both cost and probability are not definitive at this time, yet illustrated major points for discussion. The cost parameters most sensitive to incremental change in decreasing order are: the specificity of the screening test > benefits obtained from early therapy > prevalence of the disease. Benefit-cost calculations demonstrated that DRE, when performed by highly skilled examiners, had the lowest cost. However, DRE became one of the most costly detection scenarios when a minor decrease in DRE performance was assumed for more general examiners. If slightly more specific PSA usage (or assay) is developed, the higher prevalence of clinically detectable prostate cancer could make screening less costly than breast cancer screening. If we assume minimized future expenditures for terminal cancer care via reductions in therapy choices or coverage, no economic benefit for screening exists. If we also assume that potential costs to society are not roughly approximated by any benefits, we may engender inappropriate attempts at cost reduction by effectively discouraging screening in the highest risk groups.(ABSTRACT TRUNCATED AT 250 WORDS)
直肠指检（DRE）、经直肠超声检查（TRUS）和前列腺特异性抗原（PSA）的最佳组合可能更有助于检测出高危患者，以及那些继续进行筛查可能不具有成本效益的患者。我们最近对前列腺癌早期检测的成本分析使用了美国癌症协会国家前列腺癌检测项目连续三年的现有数据。边际成本分析显示，到第三年，由于对新发癌症的敏感性显著降低，直肠指检的成本大幅增加。效益成本等式承认，目前成本和概率的许多参数都不明确，但阐明了主要的讨论要点。对增量变化最敏感的成本参数按降序排列为：筛查试验的特异性＞早期治疗获得的益处＞疾病患病率。效益成本计算表明，由技术高超的检查人员进行直肠指检时，成本最低。然而，对于普通检查人员来说，如果假设直肠指检的性能略有下降，那么直肠指检就会成为成本最高的检测方案之一。如果开发出特异性稍高的PSA检测方法（或检测手段），临床上可检测到的前列腺癌较高的患病率可能会使筛查成本低于乳腺癌筛查。如果我们假设通过减少治疗选择或覆盖范围来尽量降低晚期癌症治疗的未来支出，那么筛查就不存在经济效益。如果我们还假设社会的潜在成本不能大致由任何益处来近似，那么我们可能会通过有效地劝阻高危人群进行筛查，从而引发不适当的降低成本的尝试。（摘要截断于250字）
