Transanal minimally invasive surgery endoscopic mucosal resection for rectal benign tumors and rectal carcinoids: A retrospective analysis.

[BACKGROUND] Transanal minimally invasive surgery (TAMIS) is a good choice for resection of rectal neoplasms. Endoscopic mucosal resection (EMR) is also widely used in the treatment of benign rectal tumors such as rectal polyps and rectal adenomas. However, no studies have compared the outcome of TAMIS and EMR.

[AIM] To compare the short-term outcomes after TAMIS and EMR for rectal carcinoid and benign tumors (including rectal polyps and adenomas).

[METHODS] From January 2014 to January 2019, 44 patients who received TAMIS and 53 patients who received EMR at The Fifth People's Hospital of Shanghai were selected. Primary outcomes (surgical-related) were operating time, blood loss, length of postoperative hospital stay, rate of resection margin involvement and lesion fragmentation rate. The secondary outcomes were complications such as hemorrhage, urinary retention, postoperative infection and reoperation.

[RESULTS] No significant differences were observed in terms of blood loss (12.48 ± 8.00 mL for TAMIS 11.45 ± 7.82 mL for EMR, = 0.527) and length of postoperative hospital stay (3.50 ± 1.87 d for TAMIS 2.72 ± 1.98 d for EMR, = 0.065) between the two groups. Operating time was significantly shorter for EMR compared with TAMIS (21.19 ± 9.49 min 49.95 ± 15.28 min, = 0.001). The lesion fragmentation rate in the EMR group was 22.6% (12/53) and was significantly higher than that (0%, 0/44) in the TAMIS group ( = 0.001). TAMIS was associated with a higher urinary retention rate (13.6%, 6/44 1.9%, 1/53 = 0.026) and lower hemorrhage rate (0%, 0/44 18.9%, 10/53 = 0.002). A significantly higher reoperation rate was observed in the EMR group (9.4%, 5/53 0%, 0/44 = 0.036).

[CONCLUSION] Compared with EMR, TAMIS can remove lesions more completely with effective hemostasis and lower postoperative hemorrhage and reoperation rates. TAMIS is a better choice for the treatment of rectal carcinoids.