Liu Shi-Xin, Zhou Zhi-Rui, Chen Ling-Xiao, Yang Yong-Jing, Hu Zhi-De, Zhang Tian-Song
Department of Radiation Oncology, Tumor Hospital of Jilin Province, Changchun, China E-mail :
Asian Pac J Cancer Prev. 2015;16(14):5755-62. doi: 10.7314/apjcp.2015.16.14.5755.
Short-course preoperative radiation (SCRT) with delayed surgery was found to increase pathologic complete response (pCR) rates in several trials. However, there was no clear answer on whether SCRT or long-course chemo-radiotherapy (LCRT) is more effective. Therefore we conducted this meta-analysis to evaluate the safety and efficacy of SCRT versus LCRT, both with delayed surgery, for treatment of rectal cancer.
The literature was searched from PubMed, EMBASE, Web of Science, Cochrane Library and clinicaltrials.gov up to November, 2014. Quality of the randomized controlled trials (RCTs) was evaluated according to the Cochrane's risk of bias tool of RCT. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used to rate the level of evidence. Review Manager 5.3 was employed for statistical analysis. Pooled risk ratios (RRs) and 95% confidence intervals (CIs) were calculated.
Three RCTs, with a total of 357 rectal cancer patients, were included in this systematic review. Meta- analysis results demonstrated there were no significantly differences in sphincter preservation rate, local recurrence rate, grade 3~4 acute toxicity, R0 resection rate and downstaging rate. Compared with SCRT, LCRT was associated with significant increase in the pCR rate [RR=0.49, 95%CI (0.31, 0.78), P=0.003].
In terms of sphincter preservation rate, local recurrence rate, grade 3~4 acute toxicity, R0 resection rate and downstaging rate, SCRT with delayed surgery is as effective as LCRT with delayed surgery for management of rectal cancer. LCRT significantly increased pCR rate compared with SCRT. Due to risk of bias and imprecision, further multi-center large sample RCTs were needed to confirm this conclusion.
在多项试验中发现，短程术前放疗（SCRT）联合延迟手术可提高病理完全缓解（pCR）率。然而，关于SCRT与长程放化疗（LCRT）哪种更有效尚无明确答案。因此，我们进行了这项荟萃分析，以评估SCRT与LCRT联合延迟手术治疗直肠癌的安全性和有效性。
检索截至2014年11月的PubMed、EMBASE、科学网、Cochrane图书馆和clinicaltrials.gov上的文献。根据Cochrane随机对照试验（RCT）偏倚风险工具评估随机对照试验的质量。采用推荐分级评估、制定与评价（GRADE）系统对证据水平进行分级。使用Review Manager 5.3进行统计分析。计算合并风险比（RRs）和95%置信区间（CIs）。
本系统评价纳入3项RCT，共357例直肠癌患者。荟萃分析结果显示，在保肛率、局部复发率、3~4级急性毒性反应、R0切除率和降期率方面无显著差异。与SCRT相比，LCRT的pCR率显著升高[RR=0.49，95%CI（0.31，0.78），P=0.003]。
就保肛率、局部复发率、3~4级急性毒性反应、R0切除率和降期率而言，SCRT联合延迟手术治疗直肠癌与LCRT联合延迟手术同样有效。与SCRT相比，LCRT显著提高了pCR率。由于存在偏倚风险和不精确性，需要进一步开展多中心大样本RCT来证实这一结论。
