Fall Katja, Garmo Hans, Andrén Ove, Bill-Axelson Anna, Adolfsson Jan, Adami Hans-Olov, Johansson Jan-Erik, Holmberg Lars
Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Box 281, S-171 77 Stockholm, Sweden.
J Natl Cancer Inst. 2007 Apr 4;99(7):526-32. doi: 10.1093/jnci/djk110.
Rates of long-term survival among patients with untreated localized prostate cancer are high. To avoid unnecessary treatment, tools are needed to identify the small proportion of patients who are destined to develop lethal prostate cancer.
To evaluate the accuracy of early changes in prostate-specific antigen (PSA) levels as predictors of prostate cancer outcome, we assessed serial measurements of PSA level among 267 men with localized prostate cancer in a Scandinavian cohort of men who were diagnosed between 1989 and 1999 and who were managed by watchful waiting. We then 1) fitted individual regression lines to the PSA values assessed for each patient during the first 2 years of follow-up by using three different models, 2) evaluated early PSA curve characteristics as determinants of the cumulative incidence of lethal prostate cancer and calculated hazard ratios for baseline PSA value and rate of change in PSA level to prostate cancer outcome, and 3) plotted time-dependent receiver operating characteristic (ROC) curves. All P values are two-sided.
During complete follow-up for a mean of 8.5 years, 34 patients (13%) died from prostate cancer, and 18 (7%) developed metastases but were still alive at end of follow-up. In a log-linear model, both PSA value at baseline (P = .05) and the rate of PSA change (P<.001) were associated with the development of lethal prostate cancer. In the ROC analysis, however, the accuracy of classifying the disease as either indolent or destined to progress was low, regardless of the cut point chosen for initial PSA level or rate of change in PSA level.
Although baseline PSA value and rate of PSA change are prognostic factors for lethal prostate cancer, they are poor predictors of lethal prostate cancer among patients with localized prostate cancer who are managed by watchful waiting.
未经治疗的局限性前列腺癌患者的长期生存率很高。为避免不必要的治疗，需要一些工具来识别注定会发展为致命性前列腺癌的一小部分患者。
为了评估前列腺特异性抗原（PSA）水平早期变化作为前列腺癌预后预测指标的准确性，我们在一个斯堪的纳维亚队列中评估了267例局限性前列腺癌男性患者的PSA水平系列测量值，这些患者于1989年至1999年被诊断，采用观察等待管理。然后我们1）使用三种不同模型为每位患者在随访的前两年评估的PSA值拟合个体回归线，2）评估早期PSA曲线特征作为致命性前列腺癌累积发病率的决定因素，并计算基线PSA值和PSA水平变化率与前列腺癌预后的风险比，3）绘制时间依赖性受试者工作特征（ROC）曲线。所有P值均为双侧。
在平均8.5年的完整随访期间，34例患者（13%）死于前列腺癌，18例（7%）发生转移但在随访结束时仍存活。在对数线性模型中，基线时的PSA值（P = 0.05）和PSA变化率（P<0.001）均与致命性前列腺癌的发生相关。然而，在ROC分析中，无论为初始PSA水平或PSA水平变化率选择何种切点，将疾病分类为惰性或注定进展的准确性都很低。
虽然基线PSA值和PSA变化率是致命性前列腺癌的预后因素，但在采用观察等待管理的局限性前列腺癌患者中，它们是致命性前列腺癌的不良预测指标。
