Physical recovery after local resection of non-pedunculated rectal adenomas and T1 carcinomas: endoscopic submucosal dissection versus transanal minimally invasive surgery.

Background And Aims: Rehabilitation of physical activity is an important functional outcome after endoscopic surgery. Our aim was to quantitatively assess recovery following endoscopic submucosal dissection (ESD) and transanal minimally invasive surgery (TAMIS).

Methods: In the TRIASSIC study (Netherlands Trial Register: NL7083), patients with rectal polyps >20mm were randomized between ESD and TAMIS. This ancillary study used smartwatches to track activity data for a 14-day preoperative baseline period and a 28-day postoperative recovery period. The primary endpoint for non-inferiority was the mean time to recovery (≥90% of baseline step count for two consecutive days), assessed using Weibull regression with a seven-day non-inferiority margin.

Results: Forty patients were included; 20 ESD and 20 TAMIS procedures. Median lesion size was 42.5mm (IQR 25), with 17.5% pT1RCs and 82.5% non-malignant rectal polyps. Compliance with smartwatch measurements was 98.4% (IQR 5.8). Within the 28-day timespan, 17 patients (85%) recovered in the ESD group and 15 (75%) in the TAMIS group (p=0.43). Mean recovery time was 13.9 days for ESD and 21.0 days for TAMIS, indicating non-inferiority of ESD (95%CI of difference -3.41 to 20.25). Recovery measured by smartwatch significantly correlated with self-reported recovery (Spearman's rho 0.644, p<0.001). Moderate to severe pain scores (≥4 out of 10) were reported by 15 patients (42.9%); 27.8% in the ESD group and 58.9% in the TAMIS-group (p=0.06). Increased pain scores were significantly associated with decreased physical activity (p<0.01).

Conclusions: In terms of mean time to physical recovery, ESD was non-inferior to TAMIS. Post-procedural pain was significantly associated with reduced physical activity.