Department of Radiation Oncology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Department of Radiation Oncology, St. Vincent's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Cancer Res Treat. 2018 Jul;50(3):1039-1050. doi: 10.4143/crt.2017.252. Epub 2017 Nov 21.
A pooled analysis of multi-institutional trials was performed to analyze the effect of surgical timing on tumor response by comparing short course concurrent chemoradiotherapy (CCRT) with long course CCRT followed by delayed surgery in locally advanced rectal cancer.
Three hundred patients with cT3-4N0-2 rectal adenocarcinoma were included. Long course patients from KROG 14-12 (n=150) were matched 1:1 to 150 short course patients from KROG 10-01 (NCT01129700) and KROG 11-02 (NCT01431599) according to stage, age, and other risk factors. The primary endpoint was to determine the interval between surgery and the last day of neoadjuvant CCRT which yields the best tumor response after the short course and long course CCRT. Downstaging was defined as ypT0-2N0M0 and pathologic complete response (ypCR) was defined as ypT0N0M0, respectively.
Both the long and short course groups achieved lowest downstaging rates at < 6 weeks (long 20% vs. short 8%) and highest downstaging rates at 6-7 weeks (long 44% vs. short 40%). The ypCR rates were lowest at < 6 weeks (both long and short 0%) and highest at 6-7 weeks (long 21% vs. short 11%) in both the short and long course arms. The downstaging and ypCR rates of long course group gradually declined after the peak at 6-7 weeks and those of the short course group trend to constantly increase afterwards.
It is optimal to perform surgery at least 6 weeks after both the short course and long course CCRT to obtain maximal tumor regression in locally advanced rectal adenocarcinoma.
通过比较短程同期放化疗（CCRT）与长程 CCRT 后延迟手术治疗局部进展期直肠癌，对多机构试验进行汇总分析，以分析手术时机对肿瘤反应的影响。
共纳入 300 例 cT3-4N0-2 直肠腺癌患者。KROG 14-12 中的长程组（n=150）与 KROG 10-01（NCT01129700）和 KROG 11-02（NCT01431599）中的 150 例短程组患者按分期、年龄和其他危险因素 1:1 匹配。主要终点是确定手术与新辅助 CCRT 最后一天之间的间隔，以确定短程和长程 CCRT 后获得最佳肿瘤反应的间隔。降期定义为 ypT0-2N0M0，病理完全缓解（ypCR）定义为 ypT0N0M0。
长程和短程组在<6 周时达到最低降期率（长程 20% vs. 短程 8%），在 6-7 周时达到最高降期率（长程 44% vs. 短程 40%）。ypCR 率在<6 周时最低（长程和短程均为 0%），在 6-7 周时最高（长程 21% vs. 短程 11%）。长程组的降期和 ypCR 率在 6-7 周后逐渐下降，短程组的降期和 ypCR 率则呈持续上升趋势。
对于局部进展期直肠腺癌，至少在短程和长程 CCRT 后 6 周进行手术可获得最大的肿瘤退缩。
