Muralidhar Vinayak, Xiang Michael, Orio Peter F, Martin Neil E, Beard Clair J, Feng Felix Y, Hoffman Karen E, Nguyen Paul L
Harvard-MIT Division of Health Sciences and Technology, Harvard Medical School, Boston, MA.
Department of Radiation Oncology, Stanford School of Medicine, Stanford, CA.
J Contemp Brachytherapy. 2016 Feb;8(1):1-6. doi: 10.5114/jcb.2016.58080. Epub 2016 Feb 29.
Recent retrospective data suggest that brachytherapy (BT) boost may confer a cancer-specific survival benefit in radiation-managed high-risk prostate cancer. We sought to determine whether this survival benefit would extend to the recently defined favorable high-risk subgroup of prostate cancer patients (T1c, Gleason 4 + 4 = 8, PSA < 10 ng/ml or T1c, Gleason 6, PSA > 20 ng/ml).
We identified 45,078 patients in the Surveillance, Epidemiology, and End Results database with cT1c-T3aN0M0 intermediate- to high-risk prostate cancer diagnosed 2004-2011 treated with external beam radiation therapy (EBRT) only or EBRT plus BT. We used multivariable competing risks regression to determine differences in the rate of prostate cancer-specific mortality (PCSM) after EBRT + BT or EBRT alone in patients with intermediate-risk, favorable high-risk, or other high-risk disease after adjusting for demographic and clinical factors.
EBRT + BT was not associated with an improvement in 5-year PCSM compared to EBRT alone among patients with favorable high-risk disease (1.6% vs. 1.8%; adjusted hazard ratio [AHR]: 0.56; 95% confidence interval [CI]: 0.21-1.52, p = 0.258), and intermediate-risk disease (0.8% vs. 1.0%, AHR: 0.83, 95% CI: 0.59-1.16, p = 0.270). Others with high-risk disease had significantly lower 5-year PCSM when treated with EBRT + BT compared with EBRT alone (3.9% vs. 5.3%; AHR: 0.73; 95% CI: 0.55-0.95; p = 0.022).
Brachytherapy boost is associated with a decreased rate of PCSM in some men with high-risk prostate cancer but not among patients with favorable high-risk disease. Our results suggest that the recently-defined "favorable high-risk" category may be used to personalize therapy for men with high-risk disease.
近期的回顾性数据表明，近距离放射治疗（BT）增敏可能会给接受放射治疗的高危前列腺癌患者带来癌症特异性生存获益。我们试图确定这种生存获益是否会扩展至最近定义的前列腺癌患者有利高危亚组（T1c，Gleason 4 + 4 = 8，PSA < 10 ng/ml或T1c，Gleason 6，PSA > 20 ng/ml）。
我们在监测、流行病学和最终结果数据库中识别出45,078例cT1c - T3aN0M0中高危前列腺癌患者，这些患者在2004年至2011年期间被诊断出，仅接受了外照射放疗（EBRT）或接受了EBRT加BT治疗。我们使用多变量竞争风险回归来确定在调整人口统计学和临床因素后，EBRT加BT或单独EBRT治疗的中危、有利高危或其他高危疾病患者的前列腺癌特异性死亡率（PCSM）发生率差异。
在有利高危疾病患者中，与单独EBRT相比，EBRT加BT与5年PCSM改善无关（1.6%对1.8%；调整后风险比[AHR]：0.56；95%置信区间[CI]：0.21 - 1.52，p = 0.258），在中危疾病患者中也是如此（0.8%对1.0%，AHR：0.83，95% CI：0.59 - 1.16，p = 0.270）。与单独EBRT相比，其他高危疾病患者接受EBRT加BT治疗时5年PCSM显著更低（3.9%对5.3%；AHR：0.73；95% CI：0.55 - 0.95；p = 0.022）。
近距离放射治疗增敏与部分高危前列腺癌男性患者的PCSM发生率降低相关，但在有利高危疾病患者中并非如此。我们的结果表明，最近定义的“有利高危”类别可用于为高危疾病男性患者制定个性化治疗方案。
