目的:Pd-103和I-125通常用于前列腺癌的低剂量率(LDR)近距离放射治疗。同位素类型的结果比较有限,但是Pd-103比I-125具有明显的放射生物学优势,尽管其在美国以外的可用性较低.我们评估了Pd-103与I-125LDR单药治疗前列腺癌后的肿瘤学结果。
方法:我们回顾性分析了8个机构中接受Pd-103(n=1,597)或I-125(n=7,504)治疗前列腺癌的确定性LDR单药治疗的男性的数据库。通过Kaplan-Meier单变量和Cox多变量分析,分析了通过同位素分层的无临床衰竭(FFCF)和无生化衰竭(FFBF)。对随访至少3.5年的男性,按同种型计算生化治愈率(3.5至4.5年随访期间前列腺特异性抗原水平≤0.2ng/mL),并通过单变量和多变量逻辑回归进行比较。
结果:与I-125相比,Pd-103导致较高的7年FFBF率(96.2%vs87.6%,P<0.001)和FFCF(96.5%vs94.3%,P<0.001)。在对基线因素进行多变量校正后,这种差异仍然存在(FFBF风险比[HR]=0.31,FFCFHR=0.49,均P<0.001)。Pd-103在单变量分析(比值比[OR]=5.9,P<0.001)和多变量分析(OR=6.0,P<0.001)中也与较高的治愈率相关。结果在使用两种同位素的4个机构的数据的敏感性分析中保留了显著性(n=2,971)。
结论:Pd-103单药治疗与较高的FFBF相关,FFCF,和生化治愈率,提示与I-125相比,Pd-103LDR可改善肿瘤学结局.
Pd-103 and I-125 are commonly used in low dose rate (LDR) brachytherapy for prostate cancer. Comparisons of outcomes by isotope type are limited, but Pd-103 has distinct radiobiologic advantages over I-125 despite its lesser availability outside the United States. We evaluated oncologic outcomes after Pd-103 vs I-125 LDR monotherapy for prostate cancer.
We retrospectively analyzed databases at 8 institutions for men who received definitive LDR monotherapy with Pd-103 (n = 1,597) or I-125 (n = 7,504) for prostate cancer. Freedom from clinical failure (FFCF) and freedom from biochemical failure (FFBF) stratified by isotope were analyzed by Kaplan-Meier univariate and Cox multivariate analyses. Biochemical cure rates (prostate-specific antigen level ≤ 0.2 ng/mL between 3.5 and 4.5 years of follow-up) by isotype were calculated for men with at least 3.5 years of follow-up and compared by univariate and multivariate logistic regression.
Compared with I-125, Pd-103 led to higher 7-year rates of FFBF (96.2% vs 87.6%, P < 0.001) and FFCF (96.5% vs 94.3%, P < 0.001). This difference held after multivariate adjustment for baseline factors (FFBF hazard ratio [HR] = 0.31, FFCF HR = 0.49, both P < 0.001). Pd-103 was also associated with higher cure rates on univariate (odds ratio [OR] = 5.9, P < 0.001) and multivariate (OR = 6.0, P < 0.001) analyses. Results retained significance in sensitivity analyses of data from the 4 institutions that used both isotopes (n = 2,971).
Pd-103 monotherapy was associated with higher FFBF, FFCF, and biochemical cure rates, and suggests that Pd-103 LDR may lead to improved oncologic outcomes compared with I-125.