Zagars G K
Department of Radiotherapy, University of Texas M.D. Anderson Cancer Center, Houston.
J Urol. 1994 Nov;152(5 Pt 2):1786-91. doi: 10.1016/s0022-5347(17)32386-8.
Between 1987 and 1991, 269 patients with clinical stage T1 or T2, N0 or Nx adenocarcinoma of the prostate underwent external beam radiation therapy as the sole initial treatment and were followed with serial prostate specific antigen (PSA) levels for 9 to 73 months (mean 33, median 30). Of the patients 26 had clinical evidence of disease relapse, 58 had an increasing PSA profile and 62 had either relapse or an increasing PSA. The actuarial incidence of increasing PSA was 30% at 5 years and the incidence of relapse or increasing PSA was 36% at the same time. With relapse or increasing PSA level as an end point, pretreatment PSA level, Gleason grade and serum prostatic acid phosphatase level were individually significant covariates. However, in multivariate analysis only pretreatment PSA level was significant. The 5-year actuarial rates of relapse or increasing PSA according to pretreatment PSA level were 4 ng./ml. or less-14%, greater than 4 to 10 ng./ml.-33%, greater than 10 to 30 ng./ml.-55% and greater than 30 ng./ml.-greater than 80%. Post-irradiation PSA levels at 3 and 6 months provided prognostic information additional to that inherent before treatment. However, the nadir PSA value, achieved typically at 6 to 12 months, was the most significant aspect of posttreatment PSA. Patients with a nadir PSA level of less than 1 ng./ml. fared well, with a 12% incidence of relapse or increasing PSA at 5 years. Nadir values exceeding 1 ng./ml. were associated with an increasing relapse rate as the nadir value increased, and nearly two-thirds of the cases in which the nadir exceeded 4 ng./ml. failed by 2 years. When increasing PSA was used as an end point additional to relapse, the outcome in this series was significantly worse than in an earlier series evaluated without PSA. Comparing these 2 series resulted in an estimate that PSA begins to increase approximately 4 to 5 years before the appearance of clinically overt disease. These results reveal the high significance of pretreatment PSA levels, significance of nadir PSA values after treatment, earlier detection of persistent disease by the increasing PSA profile, and the fact that total and permanent eradication of localized prostate cancer is considerably more difficult than traditionally believed. The therapeutic implications of this series, and the implications on the quantity and quality of patient lives await prospective study.
1987年至1991年间，269例临床分期为T1或T2、N0或Nx期的前列腺腺癌患者接受了外照射放疗作为唯一的初始治疗，并连续监测前列腺特异性抗原（PSA）水平9至73个月（平均33个月，中位数30个月）。这些患者中，26例有疾病复发的临床证据，58例PSA水平呈上升趋势，62例有复发或PSA水平上升的情况。PSA水平上升的精算发病率在5年时为30%，复发或PSA水平上升的发病率在同一时间为36%。以复发或PSA水平上升为终点，治疗前PSA水平、Gleason分级和血清前列腺酸性磷酸酶水平分别是显著的协变量。然而，在多变量分析中只有治疗前PSA水平是显著的。根据治疗前PSA水平，复发或PSA水平上升的5年精算率为：4 ng/ml及以下-14%，大于4至10 ng/ml-33%，大于10至30 ng/ml-55%，大于30 ng/ml-大于80%。照射后3个月和6个月的PSA水平提供了治疗前固有信息之外的预后信息。然而，通常在6至12个月达到的PSA最低点值是治疗后PSA最显著的方面。PSA最低点水平低于1 ng/ml的患者预后良好，5年时复发或PSA水平上升的发生率为12%。最低点值超过1 ng/ml与随着最低点值增加而上升的复发率相关，最低点超过4 ng/ml的病例中近三分之二在2年内复发。当将PSA水平上升作为复发之外的终点时，本系列的结果明显比早期未使用PSA评估的系列更差。比较这两个系列得出的估计是，PSA在临床明显疾病出现前约4至5年开始上升。这些结果揭示了治疗前PSA水平的高度重要性、治疗后PSA最低点值的重要性、通过PSA水平上升更早发现持续性疾病，以及局限性前列腺癌的完全和永久性根除比传统认为的要困难得多这一事实。本系列的治疗意义以及对患者生活数量和质量的影响有待前瞻性研究。
