Assessing the safety and outcomes of repeat transanal endoscopic microsurgery

Background Transanal endoscopic microsurgery (TEM) is the treatment of choice for benign rectal tumors and select early rectal cancers. This surgical approach has become ubiquitous and surgeons are seeing recurrent lesions after TEM resection. This study aims to outline the safety and outcomes of repeat TEM when compared to primary TEM procedures. Methods At St. Paul’s Hospital, demographic, surgical, pathologic, and follow-up data for patients treated by TEM are maintained in a prospectively populated database. Two groups were established for comparison: patients undergoing first TEM procedure (TEM-P) and patients undergoing repeat TEM procedure (TEM-R). Results Between 2007 and 2017, 669 patients had their first TEM procedure. Over this time frame, 57 of these patients required repeat TEM procedures, including 15 of these patients treated by 3 or more TEMs. Indications for repeat TEM included recurrence (78%), positive margins (15%), and metachronous lesions (7%). There were no differences between the groups in patient age, gender, or tumor histology. Compared to TEM-P, TEM-R had shorter operative times (38 vs. 52 min, p < 0.001), more distal lesions (5 vs. 7 cm, p < 0.004), and smaller lesions (3 vs. 4 cm, p < 0.0003). The TEM-R group had similar length of hospital stay (0.45 vs. 0.56 days, p = 0.65), rates of clear margins on pathology (81% vs. 88%, p = 0.09), and 30-day readmission rates (7% vs. 4%, p = 0.27) when compared to TEM- P group. TEM-R was more likely to be managed without suturing the surgical defect (72% vs. 32%, p < 0.0001). Repeat TEM was associated with similar post-operative complications as primary TEM graded on the Clavien–Dindo classification scale (Grade 1: 5% vs. 5%, Grade 2: 5% vs. 4%, Grade 3: 5% vs. 1%, p = 0.53). No 30-day mortality occurred in either group. Conclusions The St. Paul’s Hospital TEM experience suggests repeat TEM is a safe and feasible procedure with similar outcomes as patients undergoing first TEM.