Distal gastrectomy (DG) and total gastrectomy (TG) are the most common types of radical surgery for patients with middle-third gastric cancer (MTGC). However, the indications and benefits of the two procedures still remain controversial. The present meta-analysis aimed to compare the surgical and oncological outcomes of DG and TG in the treatment of MTGC. A rigorous literature review was performed in the databases of PubMed, Embase, Web of Science, China National Knowledge Infrastructure and Chinese BioMedical Literature to retrieve studies published up to February 2022. The Newcastle-Ottawa Scale was used to assess the quality of included studies and a meta-analysis was performed using RevMan 5.3 software. A total of 12 retrospective studies performing comparisons of DG and TG were included in the present meta-analysis. For patients who underwent DG, a lower rate of overall post-operative complications, anastomosis leakage and intro-abdominal infection was determined. No significant difference was observed between DG and TG in the 5-year overall survival when the proximal resection margin ranged from 3 to 5 cm. Although DG was associated with a higher 5-year overall survival rate when compared to TG, there was no significant difference in the stratified analyses by TNM stage. In conclusion, the prognosis of MTGC did not depend on the extent of gastrectomy. With lower complications and acceptable oncological outcomes, DG was a safe and feasible surgical procedure for MTGC when a negative proximal margin was confirmed.

Background Numerous case-control studies have reported associations between interleukin-17 (IL-17) polymorphisms and colorectal cancer; however, the results were inconsistent. The aim of this meta-analysis was to further clarify the effects of IL-17 polymorphisms on colorectal cancer susceptibility. Materials and method Relevant studies were extracted from the electronic databases PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), and the Chinese Biomedical Literature Database (CMB) up to April 2021. The odds ratio and 95% confidence interval were used to estimate the strength of the associations. Results Ten articles including 2599 cases and 2845 controls were enrolled in our research after strict literature screening. Highly significant associations between the IL-17A rs2275913 polymorphism and increased colorectal cancer susceptibility were observed in all five gene models (allelic, dominant, recessive, homozygous, and heterozygous models), and subgroup analysis based on ethnicity revealed that these associations existed not only in the Asian population but also in the Caucasian population. However, the results showed no significantly elevated colorectal cancer risk correlated with the IL-17F rs763780 polymorphism, and a slightly lower colorectal cancer susceptibility for the Caucasian population was discovered in the recessive and homozygous models of this mutation. Conclusion The IL-17A rs2275913 polymorphism may be an independent risk factor contributing to colorectal cancer susceptibility, while the IL-17F rs763780 polymorphism may decrease susceptibility to colorectal cancer. Future studies with large-scale samples are warranted to identify these associations.