中低位局部进展期直肠癌全程新辅助治疗的研究进展

The advances of total neoadjuvant therapy for locally advanced rectal cancer

新辅助放化疗增加了对进展期直肠癌的局部控制作用,但无法显著降低远处转移率和改善生存预后仍是该治疗策略的不足之处。全程新辅助治疗主张将全身化疗放在根治性手术之前进行,具有改善治疗依从性、增加肿瘤的局部控制效果、提高器官保留率等优势。目前全程新辅助治疗具体模式、化疗药物种类及剂量等缺乏共识,导致各研究结果之间差异较大。此外,巩固化疗与诱导化疗、双药化疗与三药化疗、短程放疗联合巩固化疗与长程放化疗等治疗模式的选择亦存在较大争议。

The multimodality treatment has significantly increased local control of locally advanced rectal cancer,with a superior oncologic efficacy and reduced local recurrence rate from 35%to less than 10%,and the proportion of patients receiving“watch and wait”strategy or delaying surgery increased as well.However,distant relapse is still the leading cause of cancer-related death without improved long-term survival outcomes.To improve treatment compliance and overall survival benefits,a novel strategy that delivered upfront chemotherapy prior to surgery,which is termed total neoadjuvant therapy(TNT),has been proposed.TNT has two major patterns,including induction and consolidation therapy;the former treatment pattern requires systemic chemotherapy before neoadjuvant chemoradiotherapy,while consolidation therapy refers to additional cycles of chemotherapy between neoadjuvant chemoradiotherapy and surgery.As a radiosensitizer,upfront chemotherapy not only reduces gross tumor volume,but targets occult micro-metastatic disease at an early stage.Several clinical trials have also reported that TNT achieves better local control of disease with a promising treatment compliance.And organ preservation rate is supposed to increase with an improved pathologic or clinical complete response rate.Besides,there existed no established consensus regarding to specific patterns and chemotherapy regimens and doses,which results in remarkable differences among studies.In conclusion,the exact oncologic efficacy and survival benefits of total neoadjuvant therapy still need clinical trials to confirm.