Abstract: The incidence of rectal cancer has been increasing in recent years.It leads to more attention of scholars at home and abroad,which the efficacy of rectal cancer has been improved by using neoadjuvant therapy all over the world.It is included preoperative radiotherapy,preoperative chemotherapy and preoperative chemoradiotherapy.Preoperative radiotherapy,which can be divided into short radiotherapy and conventional radiotherapy,are evaluated by comparison of T drop rate,sphincter preservation rate,complete remission rate and other indicators of clinical effect.Although the experience of pure preoperative chemotherapy is not rich enough,it still has an advantage in lowering the tumour stage and other aspects.Currently,preoperative chemoradiotherapy is a good choice for rectal cancer,because it could make an obvious advantage in the treatment,at the same time,three-dimensional radiotherapy can make target more evenly distributed and focus treatment more precise.However,neoadjuvant therapy has insufficient support in clinical in our country.So it needs to get more information for clinical effectiveness of applying preoperative chemoradiotherapy.This study is to summarize the new adjuvant treatment of rectal cancer.

Key words: Rectal cancer, Neoadjuvant therapy, Three-dimensional radiotherapy