OBJECTIVETo compare the short-term efficacy of laparoscope-assisted transanal total mesorectal excision (LA-taTME) and conventional laparoscopic TME (LTME) for rectal cancer by meta-analysis.

METHODSClinical studies that compared clinical outcomes of LA-taTME and LTME were searched from form PubMed, Embase, Ovid, CNKI and Wanfang database before January 2016. Two reviewers independently screened the articles and assessed the quality of the included studies by using the MINORS standard which involves 12 items. The score is 0-2 for each item and the maximum score is 24, and the ideal global score should be above16. RevMan 5.3 software was used for meta-analysis and outcome measures included operation time, hospital stay, number of harvested lymph node, rate of conversion, positive rate of circumferential resection margin and the rate of incomplete mesorectum.

RESULTSSeven studies were included in the analysis, and the score of all the studies was more than 16 points. A total of 479 patients (208 in LA-taTME, 271 in LTME) were enrolled. There were no significant differences in terms of age, sex, tumor location and clinical stage between two groups (all P>0.05). Results of meta-analysis showed that LA-taTME had lower rate of incomplete mesorectum (OR=0.29, 95% CI:0.10 to 0.84, P=0.02), lower rate of complications (OR=0.59, 95% CI:0.35 to 0.97, P=0.04) and shorter hospital stay (MD=-1.66, 95% CI:-3.22 to -0.11, P=0.04) than those of LTME, with significant differences. In terms of operation time (MD=-14.49, 95% CI:-37.87 to 8.90, P=0.22), number of harvested lymph node (MD=-0.45, 95% CI:-1.98 to 1.08, P=0.56), the rate of conversion (OR=0.31, 95% CI:0.08 to 1.24, P=0.10) and positive rate of circumferential resection margin (OR=0.43, 95% CI:0.17 to 1.04, P=0.06), there were no significant differences between two groups.

CONCLUSIONCompared to LTME, LA-taTME has similar short-term efficacy for rectal cancer, but it can reduce the rate of complications and rate of incomplete mesorectum.