Transanal Minimally Invasive Surgery (TAMIS) for Rectal Lesions: A Systematic Review.

Background/aims: Transanal minimally invasive surgery (TAMIS) has received attention as an alternative to transanal endoscopic microsurgery for rectal lesions. We review the effectiveness and safety of TAMIS for the treatment of rectal lesions.

Methodology: The MEDLINE, Web of Science, and Cochrane Library databases were searched using predefined inclusion criteria. The primary outcomes were positive margin rate, recurrence rate, conversion rate, range of applications, and complication rates. To derive pooled estimates of proportions with 95% Confidence Interval (CI) for the outcomes, a random effect model was used.

Results: Twelve studies including 155 patients were identified. The weighted mean size of rectal lesions was 3.3 cm (range 0.2-10 cm) and the weighted mean distance from the anal verge was 7.4 cm (range 0-20 cm). Six studies enrolled only the patients with low and mid rectal lesions mainly to avoid peritoneal entrance during excision.

Conclusions: Based on the evidence from this limited number of studies, TAMIS appears to be an effective and safe treatment for rec tal lesions. However, the clinical outcome of TAMIS according to the location of the rectal lesions needs to be clarified. Comparison with other established surgical treatments are also mandatory.