Background:
Neoadjuvant chemoradiotherapy has become the standard treatment for locally advanced rectal cancer. Neoadjuvant chemoradiotherapy not only can reduce tumor size and recurrence, but also increase the tumor resection rate and anus retention rate with very slight side effect. Comparing with preoperative chemotherapy alone, preoperative chemoradiotherapy can further reduce the local recurrence rate and downstage. Middle and low rectal cancers can benefit more from neoadjuvant chemradiotherapy than high rectal cancer.
Aim of the work:
1- Selection of suitable neoadjuvant chemoradiotherapy method with less acute and  late toxicity effect.
2- Discover which drug or combination of drugs have better results in terms of local recurrence and survival .
3- Selection of appropriate patients and irradiation modes for neoadjuvant chemoradiotherapy.
Methods:
Three major databases(PubMed,MEDLINE and Cochrane library).
The review included articles published in English in NCCN Journal and ASCO Journal from January 2012 t0 march 2018.
Conclusion:
 Preoperative chemoradiotherapy has been recommended as the standard treatment for locally advanced middle and low rectal cancer.