Purpose

There remains limited data as to the feasibility, safety, and efficacy of higher doses of elective radiation therapy to the pelvic lymph nodes in men with high-risk prostate cancer. We conducted a phase II study to evaluate moderate dose escalation to the pelvic lymph nodes using a simultaneous integrated boost to the prostate.

Methods and Materials

Patients were eligible with biopsy-proven adenocarcinoma of the prostate, a calculated lymph node risk of at least 25%, Karnofsky performance scale ≥70, and no evidence of M1 disease. Acute and late toxicity were prospectively collected at each follow-up using Common Terminology Criteria for Adverse Events version 4.0 (CTCAE v4.0). The pelvic lymph nodes were treated to a dose of 56 Gy over 28 fractions with a simultaneous integrated boost to the prostate to a total dose of 70 Gy over 28 fractions using intensity-modulated radiation therapy.

Results

Thirty patients were prospectively enrolled from October 2010 to August 2014. Median patient age was 70 years (57-83), pretreatment prostate-specific antigen was 11.5 ng/mL (3.23-111.5), T stage was T2c (T1c-T3b), and Gleason score was 9 (6-9). CTCAE v4.0 rate of any grade 1 or 2 genitourinary and gastrointestinal toxicity were 55% and 44%, respectively, and there was 1 reported acute grade 3 genitourinary and gastrointestinal toxicity, both unrelated to protocol therapy. With a median follow-up of 6.4 years, the biochemical failure free survival rate was 80.2%, and mean biochemical progression free survival was 8.3 years (95% confidence interval [CI], 7.2-9.4). The prostate cancer specific survival was 95.2%, and mean prostate cancer specific survival was 8.7 years (95% CI, 8.0-9.4). Five-year distant metastases free survival was 96%. Medians were not reached.

Conclusions

In this single arm, small, prospective feasibility study, nodal radiation therapy dose escalation was safe, feasible, and seemingly well tolerated. Rates of progression free survival are highly encouraging in this population of predominately National Comprehensive Cancer Network very high-risk patients.

中文翻译：

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剂量递增盆腔淋巴结调强放射治疗 (IMRT) 的长期结果，同时对前列腺进行大分割刺激治疗非常高危前列腺癌：一项前瞻性 II 期临床试验

目的

关于高风险前列腺癌男性盆腔淋巴结高剂量选择性放射治疗的可行性、安全性和有效性的数据仍然有限。我们进行了一项 II 期研究，以使用对前列腺的同步综合增强来评估对盆腔淋巴结的中等剂量递增。

方法和材料

经活检证实为前列腺癌的患者符合条件，计算出的淋巴结风险至少为 25%，Karnofsky 表现评分≥70，并且没有 M1 疾病的证据。在每次随访时使用不良事件通用术语标准 4.0 版 (CTCAE v4.0) 前瞻性收集急性和晚期毒性。盆腔淋巴结的剂量为 56 Gy，分 28 次分次治疗，同时使用调强放射治疗对前列腺进行总剂量为 70 Gy 分次的 28 次分次治疗。

结果

2010 年 10 月至 2014 年 8 月前瞻性纳入 30 名患者。患者年龄中位数为 70 岁（57-83），治疗前前列腺特异性抗原为 11.5 ng/mL（3.23-111.5），T 分期为 T2c（T1c-T3b），格里森得分为 9 (6-9)。CTCAE v4.0 对任何 1 级或 2 级泌尿生殖道和胃肠道毒性的发生率分别为 55% 和 44%，并且有 1 例报告了急性 3 级泌尿生殖道和胃肠道毒性，均与方案治疗无关。中位随访 6.4 年，无生化失败生存率为 80.2%，平均无生化进展生存率为 8.3 年（95% 置信区间 [CI]，7.2-9.4）。前列腺癌特异性存活率为 95.2%，平均前列腺癌特异性存活率为 8.7 年（95% CI，8.0-9.4）。五年无远处转移生存率为 96%。

结论

在这项单臂、小型、前瞻性可行性研究中，淋巴结放射治疗剂量递增是安全、可行的，并且似乎耐受性良好。在这个以国家综合癌症网络极高危患者为主的人群中，无进展生存率非常令人鼓舞。