Unger Joseph M, Thompson Ian M, LeBlanc Michael, Crowley John J, Goodman Phyllis J, Ford Leslie G, Coltman Charles A
Southwest Oncology Group Statistical Center, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.
Cancer. 2005 Apr 1;103(7):1375-80. doi: 10.1002/cncr.20919.
The potential public health impact of the recently completed Prostate Cancer Prevention Trial (PCPT) is debated. The results indicated that the period prevalence of prostate cancer was reduced by 24.8% due to finasteride, whereas an increase in the rate of high-grade tumors (Gleason score 8-10) among men who were diagnosed with cancer also was found (5.0% in the PCPT placebo arm vs. 11.9% in the PCPT finasteride arm). Whether the increased Gleason score was valid or was a histologic artifact is under investigation.
The authors estimated the number of person-years saved assuming a 24.8% reduction in the incidence of prostate cancer for 5 years among United States males age > or = 55 years. Scenarios for different proportions of patients with high-grade Gleason scores also were considered.
With a 24.8% reduction in the number of men with newly diagnosed prostate cancer, the authors estimated that 316,760 person-years would be saved due to finasteride in the United States. An absolute increase of 6.9% in the proportion of men with high-grade tumors in the United States cancer population (corresponding to the difference between the rates on the placebo and finasteride arms of the PCPT) would reduce the number of person-years saved to 262,567. For each absolute increase of 5% in the proportion of patients with high-grade tumors, the number of person-years saved would be reduced by approximately 39,000.
The results of the PCPT may have a major impact on population mortality from prostate cancer if they are applied clinically. The potential detrimental effects of an increased rate of patients who have prostate cancer with high-grade Gleason scores would be outweighed by a reduction in incidence.
近期完成的前列腺癌预防试验（PCPT）对公众健康的潜在影响存在争议。结果表明，非那雄胺使前列腺癌的期间患病率降低了24.8%，然而，在被诊断患有癌症的男性中，高级别肿瘤（ Gleason评分8 - 10）的发生率也有所增加（PCPT安慰剂组为5.0%，PCPT非那雄胺组为11.9%）。Gleason评分增加是真实存在还是组织学假象正在研究中。
作者假设美国55岁及以上男性前列腺癌发病率降低24.8%，持续5年，估算出节省的人年数。还考虑了不同比例高级别Gleason评分患者的情况。
新诊断前列腺癌的男性人数减少24.8%，作者估计在美国非那雄胺可节省316,760人年。美国癌症人群中高级别肿瘤男性比例绝对增加6.9%（对应PCPT安慰剂组和非那雄胺组发生率的差异），会使节省的人年数降至262,567。高级别肿瘤患者比例每绝对增加5%，节省的人年数会减少约39,000。
如果将PCPT的结果应用于临床，可能会对前列腺癌导致的人群死亡率产生重大影响。前列腺癌患者中Gleason评分高的发生率增加所带来的潜在有害影响，会被发病率的降低所抵消。
