Zagars G K, Pollack A
Department of Radiotherapy, University of Texas M.D. Anderson Cancer Center, Houston.
Urology. 1995 Mar;45(3):476-83. doi: 10.1016/S0090-4295(99)80019-3.
To evaluate disease outcome using serum prostate-specific antigen (PSA) as an outcome measure in patients with T1 or T2 prostate cancer treated with radiation therapy in the PSA era.
We reviewed the outcome for 461 patients with T1 (n = 205) or T2 (n = 256) prostate cancer followed for a median of 31 months after radiation therapy as the sole initial treatment. Univariate and multivariate analyses were used to delineate significant prognostic factors.
The freedom from relapse or rising PSA rate was 70% at 6 years and the survival rate was 83%. Although T stage, Gleason grade, serum prostatic acid phosphatase level, and serum PSA level were each significant determinants of outcome in univariate analysis, pretreatment PSA level was the only clearly independent covariate (P < 0.0001) in multivariate analysis. The 5-year actuarial freedom from relapse or from rising PSA levels is shown according to the pretreatment PSA level: 4 ng/mL or less (117 patients), 91%; more than 4 but 10 ng/mL or less (169 patients), 69%; more than 10 but 20 ng/mL or less (118 patients), 62%; and more than 20 ng/mL (57 patients), 38%. PSA doubling times in 75 patients with rising post-treatment profiles ranged from 1.3 to 78.2 months (mean, 14.4; median 11.3). Faster doubling times correlated significantly with adverse pretreatment prognostic factors (high-grade, high pretreatment PSA, and aneuploidy). To date, the survival rate of patients with rising PSA profiles was not depressed below the expected.
Radiation therapy is an acceptable modality for treating T1 or T2 disease and produces results comparable to those following radical prostatectomy when patients are stratified according to their pretreatment PSA value. The rapid PSA doubling times observed in patients with relapsing disease are more consistent with a "selective" rather than an "aggravation" mechanism.
在前列腺特异抗原（PSA）时代，评估以血清PSA作为疗效指标，对接受放射治疗的T1或T2期前列腺癌患者的疾病转归。
我们回顾了461例T1期（n = 205）或T2期（n = 256）前列腺癌患者的转归情况，这些患者在接受放射治疗作为唯一初始治疗后，中位随访31个月。采用单因素和多因素分析来确定显著的预后因素。
6年时无复发或PSA未升高率为70%，生存率为83%。虽然在单因素分析中，T分期、Gleason分级、血清前列腺酸性磷酸酶水平和血清PSA水平均为转归的显著决定因素，但在多因素分析中，治疗前PSA水平是唯一明确的独立协变量（P < 0.0001）。根据治疗前PSA水平显示的5年无复发或PSA未升高的精算概率如下：4 ng/mL及以下（117例患者），91%；大于4但10 ng/mL及以下（169例患者），69%；大于10但20 ng/mL及以下（118例患者），62%；大于20 ng/mL（57例患者），38%。75例治疗后PSA升高患者的PSA倍增时间为1.3至78.2个月（平均14.4个月；中位11.3个月）。较快的倍增时间与不良的治疗前预后因素（高分级、高治疗前PSA和非整倍体）显著相关。迄今为止，PSA升高患者的生存率未低于预期。
放射治疗是治疗T1或T2期疾病的可接受方式，当根据患者治疗前PSA值进行分层时，其疗效与根治性前列腺切除术后相当。复发疾病患者中观察到的快速PSA倍增时间更符合“选择性”而非“恶化”机制。
