局部进展期直肠癌全程新辅助治疗的发展与挑战

The development and challenges of total neoadjuvant therapy in locally advanced rectal cancer

局部进展期直肠癌的标准治疗是先行新辅助放化疗或短程放疗,再行全直肠系膜切除手术,术后给予辅助化疗,该模式可显著降低局部复发率,但并未改善生存。全程新辅助治疗是尝试在术前完成全部放疗和化疗,经过几项关键的随机对照临床试验结果证实,可显著提高病理完全缓解率,降低远处转移发生率,继而延长无病生存期和总生存期。对于低位直肠癌,经全程新辅助化疗获得临床完全缓解的病人,有望采取等待观察策略,实现直肠器官保留。但全程新辅助治疗仍面临不少问题和挑战,如适用人群、最佳的放疗和化疗方案及实施顺序、辅助化疗的选择等,根据高分辨率磁共振进行分层治疗也许是最佳方案。

The standard treatment for locally advanced rectal cancer,involved either neoadjuvant chemoradiotherapy or short-course radiotherapy,followed by total mesorectal resection and postoperative adjuvant chemotherapy,which could significantly reduce local recurrence rate,but overall survival is not improved.Total neoadjuvant therapy(TNT),delivering the full course of radiotherapy and chemotherapy before surgery,has been demonstrated by several landmark randomized controlled trials to significantly enhance pathologic complete response rates and reduce distant metastasis rates,thereby prolonging disease-free survival and overall survival.For low rectal cancer,patients with a complete clinical response following TNT even have the opportunity to adapt watch and wait surveillance and achieve organ preservation of the rectum.However,there are still obstacles and challenges for TNT,such as suitable population,the optimal radiotherapy and chemotherapy regimens,as well as their sequence and the choice of adjuvant chemotherapy.A stratified approach based on high-resolution MR results may be a preferred regimen.