Smith Graham D, Pickles Tom, Crook Juanita, Martin Andre-Guy, Vigneault Eric, Cury Fabio L, Morris Jim, Catton Charles, Lukka Himu, Warner Andrew, Yang Ying, Rodrigues George
University of Western Ontario, London, Ontario, Canada.
Department of Radiation Oncology, British Columbia Cancer Agency, Vancouver, British Columbia, Canada.
Int J Radiat Oncol Biol Phys. 2015 Mar 1;91(3):505-16. doi: 10.1016/j.ijrobp.2014.11.018. Epub 2015 Jan 13.
To compare, in a retrospective study, biochemical failure-free survival (bFFS) and overall survival (OS) in low-risk and intermediate-risk prostate cancer patients who received brachytherapy (BT) (either low-dose-rate brachytherapy [LDR-BT] or high-dose-rate brachytherapy with external beam radiation therapy [HDR-BT+EBRT]) versus external beam radiation therapy (EBRT) alone.
Patient data were obtained from the ProCaRS database, which contains 7974 prostate cancer patients treated with primary radiation therapy at four Canadian cancer institutions from 1994 to 2010. Propensity score matching was used to obtain the following 3 matched cohorts with balanced baseline prognostic factors: (1) low-risk LDR-BT versus EBRT; (2) intermediate-risk LDR-BT versus EBRT; and (3) intermediate-risk HDR-BT+EBRT versus EBRT. Kaplan-Meier survival analysis was performed to compare differences in bFFS (primary endpoint) and OS in the 3 matched groups.
Propensity score matching created acceptable balance in the baseline prognostic factors in all matches. Final matches included 2 1:1 matches in the intermediate-risk cohorts, LDR-BT versus EBRT (total n=254) and HDR-BT+EBRT versus EBRT (total n=388), and one 4:1 match in the low-risk cohort (LDR-BT:EBRT, total n=400). Median follow-up ranged from 2.7 to 7.3 years for the 3 matched cohorts. Kaplan-Meier survival analysis showed that all BT treatment options were associated with statistically significant improvements in bFFS when compared with EBRT in all cohorts (intermediate-risk EBRT vs LDR-BT hazard ratio [HR] 4.58, P=.001; intermediate-risk EBRT vs HDR-BT+EBRT HR 2.08, P=.007; low-risk EBRT vs LDR-BT HR 2.90, P=.004). No significant difference in OS was found in all comparisons (intermediate-risk EBRT vs LDR-BT HR 1.27, P=.687; intermediate-risk EBRT vs HDR-BT+EBRT HR 1.55, P=.470; low-risk LDR-BT vs EBRT HR 1.41, P=.500).
Propensity score matched analysis showed that BT options led to statistically significant improvements in bFFS in low- and intermediate-risk prostate cancer patient populations.
在一项回顾性研究中，比较接受近距离放射治疗（BT，包括低剂量率近距离放射治疗[LDR-BT]或高剂量率近距离放射治疗联合外照射放疗[HDR-BT+EBRT]）的低风险和中风险前列腺癌患者与单纯接受外照射放疗（EBRT）患者的无生化失败生存期（bFFS）和总生存期（OS）。
患者数据来自ProCaRS数据库，该数据库包含1994年至2010年在加拿大四家癌症机构接受原发性放射治疗的7974例前列腺癌患者。采用倾向评分匹配法获得以下3个具有平衡基线预后因素的匹配队列：（1）低风险LDR-BT与EBRT；（2）中风险LDR-BT与EBRT；（3）中风险HDR-BT+EBRT与EBRT。进行Kaplan-Meier生存分析，以比较3个匹配组中bFFS（主要终点）和OS的差异。
倾向评分匹配在所有匹配中使基线预后因素达到了可接受的平衡。最终匹配包括中风险队列中的2个1:1匹配，即LDR-BT与EBRT（总数n=254）以及HDR-BT+EBRT与EBRT（总数n=388），以及低风险队列中的1个4:1匹配（LDR-BT:EBRT，总数n=400）。3个匹配队列的中位随访时间为2.7至7.3年。Kaplan-Meier生存分析表明，与EBRT相比，所有BT治疗方案在所有队列中均与bFFS的统计学显著改善相关（中风险EBRT与LDR-BT的风险比[HR]为4.58，P=0.001；中风险EBRT与HDR-BT+EBRT的HR为2.08，P=0.007；低风险EBRT与LDR-BT的HR为2.90，P=0.004）。在所有比较中未发现OS有显著差异（中风险EBRT与LDR-BT的HR为1.27，P=0.687；中风险EBRT与HDR-BT+EBRT的HR为1.55，P=0.470；低风险LDR-BT与EBRT的HR为1.41，P=0.500）。
倾向评分匹配分析表明，BT方案在低风险和中风险前列腺癌患者群体中使bFFS有统计学显著改善。
