Department of Radiation Oncology, Dana-Farber Cancer Institute, Brigham and Women's Hospital, Boston, Massachusetts.
Harvard Medical School, Boston, Massachusetts.
Cancer. 2018 Sep 1;124(17):3528-3535. doi: 10.1002/cncr.31568. Epub 2018 Jul 5.
Partial prostate treatment has emerged as a potential method for treating patients with favorable-risk prostate cancer while minimizing toxicity. The authors previously demonstrated poor rates of biochemical disease control for patients with National Comprehensive Cancer Network (NCCN) intermediate-risk disease using partial gland treatment with brachytherapy. The objective of the current study was to estimate the rates of distant metastasis and prostate cancer-specific mortality (PCSM) for this cohort.
Between 1997 and 2007, a total of 354 men with clinical T1c disease, a prostate-specific antigen (PSA) level < 15 ng/mL, and Gleason grade ≤3 + 4 prostate cancer underwent partial prostate treatment with brachytherapy to the peripheral zone under 0.5-Tesla magnetic resonance guidance. The cumulative incidences of metastasis and PCSM for the NCCN very low-risk, low-risk, and intermediate-risk groups were estimated. Fine and Gray competing risk regression was used to evaluate clinical factors associated with time to metastasis.
A total of 22 patients developed metastases at a median of 11.0 years (interquartile range, 6.9-13.9 years). The 12-year metastasis rates for patients with very low-risk, low-risk, and intermediate-risk disease were 0.8% (95% confidence interval [95% CI], 0.1%-4.4%), 8.7% (95% CI, 3.4%-17.2%), and 15.7% (95% CI, 5.7%-30.2%), respectively, and the 12-year PCSM estimates were 1.6% (95% CI, 0.1%-7.6%), 1.4% (95% CI, 0.1%-6.8%), and 8.2% (95% CI, 1.9%-20.7%), respectively. On multivariate analysis, NCCN risk category (low risk: hazard ratio, 6.34 [95% CI, 1.18-34.06; P = .03] and intermediate risk: hazard ratio, 6.98 [95% CI, 1.23-39.73; P = .03]) was found to be significantly associated with the time to metastasis.
Partial prostate treatment with brachytherapy may be associated with higher rates of distant metastasis and PCSM for patients with intermediate-risk disease after long-term follow-up. Treatment of less than the full gland may not be appropriate for this cohort.
前列腺部分治疗已成为治疗具有有利风险的前列腺癌患者的一种潜在方法，同时最大限度地降低毒性。作者之前曾证明，使用近距离放射治疗对具有国家综合癌症网络（NCCN）中危疾病的患者进行部分腺体治疗，其生化疾病控制率较差。本研究的目的是估计该队列的远处转移和前列腺癌特异性死亡率（PCSM）的发生率。
1997 年至 2007 年，共有 354 名临床 T1c 疾病、前列腺特异性抗原（PSA）水平<15ng/mL 和 Gleason 分级≤3+4 前列腺癌患者接受了 0.5 特斯拉磁共振引导下的外周区近距离放射治疗。估计 NCCN 极低危、低危和中危组的转移和 PCSM 的累积发生率。精细和灰色竞争风险回归用于评估与转移时间相关的临床因素。
共有 22 例患者在中位数为 11.0 年（四分位距，6.9-13.9 年）时发生转移。极低危、低危和中危患者的 12 年转移率分别为 0.8%（95%置信区间[95%CI]，0.1%-4.4%）、8.7%（95%CI，3.4%-17.2%）和 15.7%（95%CI，5.7%-30.2%），12 年 PCSM 估计值分别为 1.6%（95%CI，0.1%-7.6%）、1.4%（95%CI，0.1%-6.8%）和 8.2%（95%CI，1.9%-20.7%）。多变量分析显示，NCCN 风险类别（低危：风险比，6.34[95%CI，1.18-34.06；P=0.03]和中危：风险比，6.98[95%CI，1.23-39.73；P=0.03]）与转移时间显著相关。
长期随访后，近距离放射治疗的前列腺部分治疗可能与中危疾病患者的远处转移和 PCSM 发生率较高相关。对于该队列，治疗小于整个腺体可能不合适。
