Review and prospect of neoadjuvant chemoradiotherapy combined with immunotherapy in locally advanced rectal cancer

Abstract

For locally advanced rectal cancer (LARC), the standard treatment of neoadjuvant chemoradiotherapy (nCRT) followed by total mesorectal excision (TME) leaded to limited tumor regression grade and organ preservation rate, and didn’t decrease the rate of distant metastasis. Radiotherapy can promote the immune response and has good synergistic effect with immunotherapy, which is likely to overcome the treatment difficulty of the microsatellite stable(MSS) colorectal cancer. Recently, multiple clinical trials are ongoing in terms of the combination of nCRT and immunotherapy in LARC. Most of them have achieved promising complete response rates, providing new treatment options for preservation of organ functions in mid-low MSS LARC. Large-scale randomized controlled trials are needed in the future to validate these findings and explore the benefit of organ preservation and long-term survival. In addition, studies are still needed on the optimal combination patterns of radiotherapy and immunotherapy and the precise efficacy evaluation, etc.

Keywords

• |locally advanced rectal cancer(larc)|neoadjuvant chemoradiotherapy|immunotherapy|complete response|organ preservation