Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL.
Department of Radiation Oncology, Eastern Carolina University, Greenville, NC.
Clin Lung Cancer. 2018 Jan;19(1):e123-e130. doi: 10.1016/j.cllc.2017.06.009. Epub 2017 Jul 8.
A previous meta-analysis (MA) found postoperative radiotherapy (PORT) in lung cancer patients to be detrimental in N0/N1 patients and equivocal in the N2 setting. We hypothesized that treatment plans generated using MA protocols had worse dosimetric outcomes compared to modern plans.
We retrieved plans for 13 patients who received PORT with modern planning. A plan was recreated for each patient using the 8 protocols included in MA. Dosimetric values were then compared between the modern and simulated MA plans.
A total of 104 MA plans were generated. Median prescribed dose was 50.4 (range, 50-60) Gy in the modern plans and 53.2 (30-60) Gy in the MA protocols. Median planning volume coverage was 96% (93%-100%) in the modern plans, versus 58% (0%-100%) in the MA plans (P < .001). Internal target volume coverage was 100% (99%-100%) versus 65% (0%-100%), respectively (P < .001). Organs at risk received the following doses: spinal cord maximum dose, 36.8 (4.6-50.4) Gy versus 46.8 (2.9-74.0) Gy (P < .001); esophageal mean dose, 22.9 (5.5-35) Gy versus 30.5 (11.1-52.5) Gy (P = .003); heart V30 (percentage of volume of an organ receiving at least a dose of 30 Gy), 16% (0%-45%) versus 35% (0%-79%) (P = .047); mean lung dose, 12.4 (3.4-24.3) Gy versus 14.8 (4.1-27.4) Gy (P = .008); and lung V20, 18% (4%-34%) versus 25% (8%-67%) (P = .023).
We quantitatively confirm the inferiority of the techniques used in the PORT MA. Our analysis showed a lower therapeutic ratio in the MA plans, which may explain the poor outcomes in the MA. The findings of the MA are not relevant in the era of modern treatment planning.
先前的荟萃分析（MA）发现肺癌患者术后放疗（PORT）对 N0/N1 患者有害，而在 N2 情况下则不确定。我们假设使用 MA 方案生成的治疗计划与现代计划相比，在剂量学结果方面更差。
我们检索了 13 例接受现代计划 PORT 的患者的计划。为每位患者使用 MA 中包含的 8 种方案重新创建了一个计划。然后比较现代计划和模拟 MA 计划之间的剂量学值。
共生成 104 个 MA 计划。现代计划中规定剂量的中位数为 50.4（范围 50-60）Gy，MA 方案中为 53.2（30-60）Gy。现代计划中计划体积覆盖率的中位数为 96%（93%-100%），而 MA 方案中为 58%（0%-100%）（P<0.001）。内部靶区覆盖率分别为 100%（99%-100%）和 65%（0%-100%）（P<0.001）。危险器官接受以下剂量：脊髓最大剂量，36.8（4.6-50.4）Gy 与 46.8（2.9-74.0）Gy（P<0.001）；食管平均剂量，22.9（5.5-35）Gy 与 30.5（11.1-52.5）Gy（P=0.003）；心脏 V30（器官接收至少 30Gy 剂量的体积百分比），16%（0%-45%）与 35%（0%-79%）（P=0.047）；平均肺剂量，12.4（3.4-24.3）Gy 与 14.8（4.1-27.4）Gy（P=0.008）；和肺 V20，18%（4%-34%）与 25%（8%-67%）（P=0.023）。
我们定量证实了 PORT MA 中使用的技术的劣势。我们的分析表明 MA 计划中的治疗比更低，这可能解释了 MA 中的不良结果。在现代治疗计划时代，MA 的结果并不相关。
