INSERM U1018, Centre for Research in Epidemiology and Population Health, Laboratory "Radiation Epidemiology & Cancer Survivorship", Gustave Roussy Cancer Campus, Villejuif, France.
Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, United States.
Radiother Oncol. 2020 Oct;151:33-39. doi: 10.1016/j.radonc.2020.07.022. Epub 2020 Jul 15.
To investigate the relationship between oesophagus dose-volume distribution and long-term risk of oesophageal cancer after radiation therapy for breast cancer.
In a case-control study nested within a cohort of 289,748 ≥5-year survivors of female breast cancer treated in 1943-2003 in five countries, doses to the second primary cancer (D) and individual dose-volume histograms (DVH) to the entire oesophagus were reconstructed for 252 oesophageal cancer cases and 488 matched controls (median follow-up time: 13, range: 5-37 years). Using conditional logistic regression, we estimated excess odds ratios (EOR) of oesophageal cancer associated with DVH metrics. We also investigated whether DVH metrics confounded or modified D-related -risk estimates.
Among the DVH metrics evaluated, median dose (D) to the entire oesophagus had the best statistical performance for estimating risk of all histological types combined (EOR/Gy = 0.071, 95% confidence interval [CI]: 0.018 to 0.206). For squamous cell carcinoma, the most common subtype, the EOR/Gy for D increased by 31% (95% CI: 3% to 205%) for each increment of 10% of V30 (p = 0.02). Adjusting for DVH metrics did not materially change the EOR/Gy for D, but there was a borderline significant positive interaction between D and V30 (p = 0.07).
This first study investigating the relationship between oesophagus dose-volume distribution and oesophageal cancer risk showed an increased risk per Gy for D with larger volumes irradiated at high doses. While current techniques allows better oesophagus sparing, constraints applied to D and V30 could potentially further reduce the risk of oesophageal cancer.
研究乳腺癌放射治疗后食管剂量-体积分布与长期食管癌风险的关系。
在一项嵌套于 1943 年至 2003 年期间在五个国家接受治疗的 289748 例乳腺癌 5 年以上幸存者队列的病例对照研究中，为 252 例食管癌病例和 488 例匹配对照（中位随访时间：13 年，范围：5-37 年）重建了第二原发癌（D）剂量和整个食管的个体剂量-体积直方图（DVH）。使用条件逻辑回归，我们估计了与 DVH 指标相关的食管癌超额比值比（EOR）。我们还研究了 DVH 指标是否会混淆或改变与 D 相关的风险估计值。
在所评估的 DVH 指标中，整个食管的中位剂量（D）在估计所有组织学类型综合风险方面具有最佳的统计学性能（EOR/Gy=0.071，95%置信区间 [CI]：0.018 至 0.206）。对于最常见的鳞状细胞癌亚型，D 每增加 10%V30 时，EOR/Gy 增加 31%（95%CI：3%至 205%）（p=0.02）。调整 DVH 指标并没有实质性地改变 D 的 EOR/Gy，但 D 与 V30 之间存在边缘显著的正交互作用（p=0.07）。
这项首次研究表明，食管剂量-体积分布与食管癌风险之间存在正相关关系，随着高剂量照射体积的增加，D 每增加 1Gy 的风险也随之增加。虽然目前的技术可以更好地保护食管，但对 D 和 V30 的限制可能会进一步降低食管癌的风险。
