Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX.
Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY.
Clin Lung Cancer. 2021 Sep;22(5):e745-e755. doi: 10.1016/j.cllc.2021.02.002. Epub 2021 Feb 7.
Postoperative radiation therapy (PORT) for non-small-cell lung cancer remains controversial with studies showing no overall survival (OS) benefit in the setting of excessive cardiopulmonary toxicity. Proton beam therapy (PBT) can potentially reduce toxicity with improved organ-at-risk sparing. We evaluated outcomes of PORT patients treated with PBT and intensity-modulated radiation therapy (IMRT).
This is a retrospective review of 136 PORT patients (61 PBT, 75 IMRT) treated from 2003 to 2016. A Kaplan-Meier analysis was performed to assess oncologic outcomes. A Cox regression was conducted to identify associated factors. Total toxicity burden (TTB) was defined as grade ≥ 2 pneumonitis, cardiac, or esophageal toxicity.
Median OS was 76 and 46 months for PBT and IMRT with corresponding 1- and 5-year OS of 85.3%, 50.9% and 89.3%, 37.2% (P = .38), respectively. V30 Gy heart (odds ratio [OR], 144.9; 95% confidence interval [CI], 2.91-7214; P = .013) and V5 Gy lung (OR, 15.8; 95% CI, 1.22-202.7; P = .03) were predictive of OS. Organ-at-risk sparing was improved with PBT versus IMRT; mean heart 2.0 versus 7.4 Gy (P < .01), V30 Gy heart 2.6% versus 10.7% (P < .01), mean lung 7.9 versus 10.4 Gy (P = .042), V5 Gy lung 23.4% versus 42.1% (P < .01), and V10 Gy lung 20.4% versus 29.6% (P < .01). TTB was reduced with PBT (OR, 0.35; 95% CI, 0.15-0.83; P = .017). Rates of cardiac toxicity were 14.7% IMRT and 4.9% PBT (P = .09). Rates of ≥ grade 2 pneumonitis were 17.0% IMRT and 4.9% PBT (P = .104).
PBT improved cardiac and lung sparing and reduced toxicity compared with IMRT. Considering the impact of cardiopulmonary toxicity on PORT outcomes, PBT warrants prospective evaluation.
对于非小细胞肺癌，术后放射治疗（PORT）仍存在争议，研究表明在心肺毒性过大的情况下，PORT 并不能带来总生存期（OS）的获益。质子束治疗（PBT）可以通过改善危及器官的保护来降低毒性。我们评估了接受 PBT 和调强放射治疗（IMRT）治疗的 PORT 患者的结局。
这是一项对 2003 年至 2016 年间接受 PORT 治疗的 136 例患者（61 例接受 PBT，75 例接受 IMRT）的回顾性分析。采用 Kaplan-Meier 分析评估肿瘤学结局。采用 Cox 回归分析确定相关因素。总毒性负担（TTB）定义为≥2 级的肺炎、心脏或食管毒性。
PBT 和 IMRT 的中位 OS 分别为 76 个月和 46 个月，相应的 1 年和 5 年 OS 率分别为 85.3%、50.9%和 89.3%、37.2%（P=0.38）。V30 Gy 心脏（比值比 [OR]，144.9；95%置信区间 [CI]，2.91-7214；P=0.013）和 V5 Gy 肺（OR，15.8；95%CI，1.22-202.7；P=0.03）是 OS 的预测因素。与 IMRT 相比，PBT 实现了更好的危及器官保护；平均心脏剂量 2.0 Gy 与 7.4 Gy（P<0.01），V30 Gy 心脏 2.6%与 10.7%（P<0.01），平均肺剂量 7.9 Gy 与 10.4 Gy（P=0.042），V5 Gy 肺 23.4%与 42.1%（P<0.01），V10 Gy 肺 20.4%与 29.6%（P<0.01）。PBT 降低了 TTB（OR，0.35；95%CI，0.15-0.83；P=0.017）。IMRT 的心脏毒性发生率为 14.7%，PBT 为 4.9%（P=0.09）。≥2 级肺炎发生率分别为 17.0%的 IMRT 和 4.9%的 PBT（P=0.104）。
与 IMRT 相比，PBT 改善了心脏和肺的保护并降低了毒性。鉴于心肺毒性对 PORT 结局的影响，PBT 值得前瞻性评估。
