Total extraperitoneal (TEP) versus laparoscopic transabdominal preperitoneal (TAPP) hernioplasty: systematic review and trial sequential analysis of randomized controlled trials

PURPOSE: To examine the updated evidence on safety, effectiveness, and outcomes of the totally extraperitoneal (TEP) versus the laparoscopic transabdominal preperitoneal (TAPP) repair and to explore the timely tendency variations favoring one treatment over another. METHODS: Systematic review and trial sequential analysis (TSA) of randomized controlled trials (RCTs). MEDLINE, Scopus, Web of Science, Cochrane Central Library, and ClinicalTrials.gov were consulted. Risk Ratio (RR), weighted mean difference (WMD), and 95% confidence intervals (CI) were used as pooled effect size measures. RESULTS: Fifteen RCTs were included (1359 patients). Of these, 702 (51.6%) underwent TAPP and 657 (48.4%) TEP repair. The age of the patients ranged from 18 to 92 years and 87.9% were males. The estimated pooled RR for hernia recurrence (RR = 0.83; 95% CI 0.35–1.96) and chronic pain (RR = 1.51; 95% CI 0.54–4.22) were similar for TEP vs. TAPP. The TSA shows a cumulative z-curve without crossing the monitoring boundaries line (Z = 1.96), thus supporting true negative results while the information size was calculated as adequate for both outcomes. No significant differences were found in term of early postoperative pain, operative time, wound-related complications, hospital length of stay, return to work/daily activities, and costs. CONCLUSIONS: TEP and TAPP repair seems comparable in terms of postoperative hernia recurrence and chronic pain. The cumulative evidence and information size are sufficient to provide a conclusive evidence on recurrence and chronic pain. Similar trials or meta-analyses seem unlikely to show diverse results and should be discouraged. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10029-021-02407-7.