BACKGROUND In recent years, intraoperative radiotherapy (IORT) has been increasingly used for the treatment of rectal cancer. However, the efficacy and safety of IORT for the treatment of rectal cancer are still controversial. AIM To evaluate the value of IORT for patients with rectal cancer. METHODS We searched PubMed, Embase, Cochrane Library, Web of Science databases, and conference abstracts and included randomized controlled trials and observational studies on IORT vs non-IORT for rectal cancer. Dichotomous variables were evaluated by odds ratio (OR) and 95% confidence interval (CI), hazard ratio (HR) and 95%CI was used as a summary statistic of survival outcomes. Statistical analyses were performed using Stata V.15.0 and Review Manager 5.3 software. RESULTS In this study, 3 randomized controlled studies and 12 observational studies were included with a total of 1460 patients, who are mainly residents of Europe, the United States, and Asia. Our results did not show significant differences in 5-year overall survival (HR = 0.80, 95%CI = 0.60-1.06; P = 0.126); 5-year disease-free survival (HR = 0.94, 95%CI = 0.73-1.22; P = 0.650); abscess (OR = 1.10, 95%CI = 0.67-1.80; P = 0.713), fistulae (OR = 0.79, 95%CI = 0.33-1.89; P = 0.600); wound complication (OR = 1.21, 95%CI = 0.62-2.36; P = 0.575); anastomotic leakage (OR = 1.09, 95%CI = 0.59-2.02; P = 0.775); and neurogenic bladder dysfunction (OR = 0.69, 95%CI = 0.31-1.55; P = 0.369). However, the meta-analysis of 5-year local control was significantly different (OR = 3.07, 95%CI = 1.66-5.66; P = 0.000). CONCLUSION The advantage of IORT is mainly reflected in 5-year local control, but it is not statistically significant for 5-year overall survival, 5-year disease-free survival, and complications.

Lateral lymph node metastasis in rectal cancer was first reported in the 1950s, since then, there has been an on-going debate about the value of lateral lymph node dis (LLND) in the management of rectal cancer. We carried out a systematic review and meta-analysis to evaluate the value of LLND for the patients with rectal cancer. To collect clinical studies for the comparison of LLND and non-LLND in patients with rectal cancer, PubMed, Embase, Cochrane Library, Web of Science, and Google Scholar databases were searched from inception to 2019. A total of 26 studies, including 6865 patients were enrolled. Data processing and statistical analyses were performed using Stata V.15.0 software and Review Manager 5.3 software. Outcome measures included the 5-year survival rate, recurrence rate, perioperative outcomes, urinary function, and male sexual function. Regarding efficacy, our meta-analysis results showed no difference in 5-year disease-free survival rate and local recurrences between the two groups, the Hazard Ratio (HR) and 95% confidence interval (CI) was 1.07 and 0.89 to 1.28 (P = 0.496), and the Odds Ratio(OR) and 95% CI were 0.90 and 0.76 to 1.06 (P = 0.208), respectively. Concerning safety, the incidence of urinary dysfunction and male sexual dysfunction was significantly increased in the LLND group (OR = 2.14, 95%CI = 1.21-3.79, P = 0.009), and (OR = 4.19, 95%CI = 1.55-11.33, P = 0.005), respectively. In conclusion, LLND did not improve the long-term prognosis of patients with rectal cancer, and was associated with increased urinary dysfunction and male sexual dysfunction.