Short-course versus long-course neoadjuvant radiotherapy combined with delayed surgery for locally advanced rectal cancer: a Meta-analysis

Abstract

Objective Short-course neoadjuvant radiotherapy (SCRT) combined with delayed surgery seems to be safer than SCRT in combination with immediate surgery. However, the clinical efficacy between SCRT and long-course neoadjuvant radiotherapy (LCRT) combined with delayed surgery has not been compared. Therefore, this meta-analysis was performed to compare the safety and efficacy between SCRT and LCRT followed by delayed surgery in patients with locally advanced rectal cancer. Methods Relevant literatures were searched using relevant databases. Baseline characteristics and treatment results of patients were extracted. The included studies were subject to bias risk assessment. Evidence assessment and data analysis were conducted. Results A total of 7 studies with 4967 patients were included. Meta-analysis results illustrated no statistical significance between two groups in terms of sphincter preservation rate, R0 resection rate, postoperative complications, local recurrence rate (LRR), distant metastasis, recurrence-free survival (RFS), overall survival (OS), length of hospital stay and acute radiotherapy toxicity (all P>0.05). Compared with SCRT with delayed surgery, LCRT with delayed surgery was associated with a significant increase in the tumor downstaging rate (RR=0.84, 95%CI=0.76-0.93, P<0.05) and a considerable increase in pathologically complete remission rate (RR=0.46, 95%CI=0.34-0.61, P<0.05). Conclusions SCRT with delayed surgery is as effective as LCRT with delayed surgery in terms of sphincter preservation rate, R0 resection rate, postoperative complications, LRR, RFS, OS, grade Ⅲ-Ⅳ acute toxicity and length of hospital stay. However, LCRT in combination with delayed surgery enhances the tumor downstaging rate and pathologically complete remission rate. Key words: Rectal neoplasm/neoadjuvant radiotherapy; Rectal neoplasm/surgery; Meta-analysis