Pollack Alan, Hanlon Alexandra L, Movsas Benjamin, Hanks Gerald E, Uzzo Robert, Horwitz Eric M
Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
Int J Radiat Oncol Biol Phys. 2003 Sep 1;57(1):19-23. doi: 10.1016/s0360-3016(03)00538-8.
Biochemical failure (BF), defined by a rising prostate-specific antigen (PSA) profile, is an early surrogate of treatment failure. However, little evidence is available to show that BF is associated with death for patents with prostate cancer treated with radiotherapy. We examined the relationship between BF and death from prostate cancer.
A total of 942 patients were treated between 1987 and 1998 with external beam radiotherapy who had sufficient PSA determinations in follow-up for the analyses described. The median radiation dose was 72 Gy, median PSA was 9.9 ng/mL, and median follow-up was 73 months. The American Society for Therapeutic Radiology and Oncology consensus definition was used to define BF. Kaplan-Meier calculations were from the start of radiotherapy. Cox proportional hazards regression multivariate analyses were used to investigate the association of BF (time-dependent variable) and other factors to distant metastasis (DM), cause-specific death (CSD), and overall death (OD). The year of treatment was included in some of the multivariate analyses to correct for potential unknown factors that may have occurred during the years of the study, such as stage migration.
BF was observed in 316 patients (34%), and 66 (7%) experienced DM, 32 (3%) died of prostate cancer, and 230 (24%) died overall during the study period. The Kaplan-Meier 5-year rate estimates from the start of treatment for BF, DM, CSD, and OD were 38%, 6%, 3%, and 13%, respectively. All patients with DM had BF. In multivariate analyses, BF was associated with DM and CSD, but not OD. The inclusion of the year of treatment did not alter these relationships.
BF, as a time-dependent covariate, was the strongest determinant of DM and was also very significantly related to CSD. The inclusion of the year of treatment had little effect on these associations. Longer follow-up is needed to determine conclusively the relationship of BF to OD.
生化失败（BF）由前列腺特异性抗原（PSA）水平升高来定义，是治疗失败的早期替代指标。然而，几乎没有证据表明BF与接受放疗的前列腺癌患者的死亡相关。我们研究了BF与前列腺癌死亡之间的关系。
1987年至1998年间，共有942例患者接受了外照射放疗，这些患者在随访中有足够的PSA测定值用于所述分析。中位放射剂量为72 Gy，中位PSA为9.9 ng/mL，中位随访时间为73个月。采用美国放射肿瘤学会的共识定义来定义BF。Kaplan-Meier计算从放疗开始时进行。采用Cox比例风险回归多变量分析来研究BF（时间依赖性变量）及其他因素与远处转移（DM）、特定病因死亡（CSD）和总死亡（OD）之间的关联。在一些多变量分析中纳入了治疗年份，以校正研究期间可能出现的潜在未知因素，如分期迁移。
316例患者（34%）出现BF，66例（7%）发生DM，32例（3%）死于前列腺癌，230例（24%）在研究期间总体死亡。从治疗开始时起，BF、DM、CSD和OD的Kaplan-Meier 5年发生率估计分别为38%、6%、3%和13%。所有发生DM的患者均有BF。在多变量分析中，BF与DM和CSD相关，但与OD无关。纳入治疗年份并未改变这些关系。
BF作为时间依赖性协变量，是DM的最强决定因素，也与CSD非常显著相关。纳入治疗年份对这些关联影响不大？需要更长时间的随访来最终确定BF与OD之间的关系。 （注：最后一句“纳入治疗年份对这些关联影响不大？”原文问号疑似有误，译文按正确理解翻译）
