Objective:To evaluate the effect of microvascular invasion (MVI) on postoperative prognosis of microhepatocellular carcinoma by a meta-analysis system.Methods:Relevant literatures in PubMed, Cochrane Library, Embase, CNKI, VIP and Wanfang databases were systematically searched. The search period was from January 2012 to January 2022. The Chinese search terms were "liver cancer" , "hepatocellular carcinoma" , "2 cm" , "microvascular invasion" , and "prognosis" . The English search terms were "small" , "solitary small" , "up to 2 cm" , "< 2 cm" , "liver" , "hepatocellular carcinoma" , "microvascular invasion" . The differences in prognosis of patients with microhepatocellular carcinoma in MVI(+ ) group and MVI(-) group were compared. Meta-analysis was performed using Review Manager 5.4 software.Results:Finally, 7 articles were included in the systematic review, with a total of 1 319 patients. All included literatures were scored ≥7 on the modified Newcastle-Ottawa scale. The results of meta-analysis showed that there were no significant differences in 1-year overall survival (OS) between MVI(+ ) group and MVI(-) group ( OR=3.14, 95% CI: 0.92-10.72, P=0.068). The 5-year OS time of patients in the MVI(+ ) group was shorter than that in the MVI(-) group, and the differences were statistically significant ( OR=2.34, 95% CI: 1.62-3.36, P<0.001). The 1-year and 5-year disease-free survival of the MVI(-) group were better than those of the MVI(+ ) group, and the difference was statistically significant (1-year: OR=3.09, 95% CI: 1.75-5.44, P<0.001; 5 years: OR=1.76, 95% CI: 1.24-2.51, P=0.002). Conclusion:The 5-year and long-term survival of MVI(+ ) patients with microhepatocellular carcinoma was poor, and the postoperative recurrence rate was high.

Malocclusion,identified by the World Health Organization(WHO)as one of three major oral diseases,profoundly impacts the dental-maxillofacial functions,facial esthetics,and long-term development of～260 million children in China.Beyond its physical manifestations,malocclusion also significantly influences the psycho-social well-being of these children.Timely intervention in malocclusion can foster an environment conducive to dental-maxillofacial development and substantially decrease the incidence of malocclusion or reduce the severity and complexity of malocclusion in the permanent dentition,by mitigating the negative impact of abnormal environmental influences on the growth.Early orthodontic treatment encompasses accurate identification and treatment of dental and maxillofacial morphological and functional abnormalities during various stages of dental-maxillofacial development,ranging from fetal stages to the early permanent dentition phase.From an economic and societal standpoint,the urgency for effective early orthodontic treatments for malocclusions in childhood cannot be overstated,underlining its profound practical and social importance.This consensus paper discusses the characteristics and the detrimental effects of malocclusion in children,emphasizing critical need for early treatment.It elaborates on corresponding core principles and fundamental approaches in early orthodontics,proposing comprehensive guidance for preventive and interceptive orthodontic treatment,serving as a reference for clinicians engaged in early orthodontic treatment.