Department of Radiation Oncology.
Department of Radiation Oncology, Penn State Cancer Institute, Hershey, PA.
Am J Clin Oncol. 2019 Jan;42(1):46-55. doi: 10.1097/COC.0000000000000472.
To determine whether increasing biologically effective dose (BED) with stereotactic body radiation therapy (SBRT) is associated with improved local control (LC) or toxicities in patients with locally advanced pancreatic cancer.
A PICOS/PRISMA/MOOSE selection protocol was used to identify 15 studies across 12 institutions in 5 countries where patients received definitive SBRT for nonmetastatic disease. Biologically equivalent doses were calculated with an α/β of 10 (ie, BED10) for LC and acute toxicity and 3 (ie, BED3) for late toxicity. Fixed and random effects models were used to characterize LC and grade 3/4 toxicities by BED.
There were 508 patients included with a median follow-up time of 9.1 months. The median dose was 30 Gy, and the most common regimen was 30 Gy/5 fractions. There was no significant difference in LC rates at 1 year between the BED10<70 Gy versus ≥70 Gy groups, with an estimate of 0.60 (95% confidence interval [CI], 0.36-0.81) versus 0.83 (95% CI, 0.63-0.97), respectively. There was no significant difference in acute toxicity rates between the BED10<70 Gy versus ≥70 Gy groups, with an estimate of 0.02 (95% CI, 0.00-0.08) versus 0.05 (95% CI, 0.00-0.22), respectively. Given the dose distribution across studies, 3 intervals were used to characterize BED3. There were no significant differences in late toxicity among those receiving BED3<100, 100 to 200, or >200 Gy.
SBRT for pancreatic cancer results in LC rates of 60% to 83% and clinically significant toxicity of <7%. Increasing BED10 beyond 70 Gy was not associated with increased rates of 1-year LC or acute toxicity. Increasing BED3 beyond 100 Gy was not associated with increased rates of late toxicity.
确定立体定向体部放射治疗（SBRT）中增加生物有效剂量（BED）是否与局部控制（LC）的改善或局部晚期胰腺癌患者的毒性相关。
使用 PICOS/PRISMA/MOOSE 选择方案，在 5 个国家的 12 个机构中确定了 15 项研究，这些研究中患者接受了非转移性疾病的确定性 SBRT。使用 α/β 为 10（即 BED10）计算 LC 和急性毒性的等效生物剂量，以及使用 α/β 为 3（即 BED3）计算晚期毒性的等效生物剂量。使用固定和随机效应模型来描述 BED 下的 LC 和 3/4 级毒性。
共有 508 例患者纳入研究，中位随访时间为 9.1 个月。中位剂量为 30Gy，最常见的方案为 30Gy/5 次。在 1 年时，BED10<70Gy 组与≥70Gy 组之间的 LC 率无显著差异，估计值分别为 0.60（95%置信区间[CI]，0.36-0.81）和 0.83（95% CI，0.63-0.97）。BED10<70Gy 组与≥70Gy 组之间的急性毒性率无显著差异，估计值分别为 0.02（95% CI，0.00-0.08）和 0.05（95% CI，0.00-0.22）。鉴于研究中的剂量分布，使用 3 个区间来描述 BED3。接受 BED3<100、100-200 和>200Gy 的患者之间的晚期毒性无显著差异。
SBRT 治疗胰腺癌的 LC 率为 60%至 83%，且毒性较小，<7%。将 BED10 增加到 70Gy 以上并不会增加 1 年时的 LC 率或急性毒性。将 BED3 增加到 100Gy 以上并不会增加晚期毒性的发生率。
