This section describes safety outcomes from the published literature that the committee considered as part of the evidence about this procedure. For more detailed information on the evidence, see the interventional procedure overview.
Minor bleeding was reported in 4% (1/25) of patients treated by endoscopic full thickness resection (EFTR) for colonic polyps in a case series of 25 patients. Bleeding was reported in 3% (5/180) of patients treated by EFTR in an unpublished case series of 180 patients with low gastrointestinal tract polyps. Bleeding was reported in 5% (4/87) of patients treated by EFTR whose data was recorded in an unpublished registry of 87 patients with gastrointestinal polyps.
Bowel perforation was reported in 3% (5/180) of patients in the unpublished case series of 180 patients. Perforation was reported in 6% (5/87) of patients and anastomotic leak needing surgery was reported in 1% (1/87) of patients in the unpublished registry of 87 patients.
In the case series of 25 patients, 8% (2/24) of patients had subsequent surgical resection after the diagnosis of high-risk adenocarcinoma. However, histology of the surgical specimen revealed EFTR had completely removed the tumour in the initial resection. Further surgery after EFTR of lesions in the lower gastrointestinal tract was done in 7% (13/180) of patients in the unpublished case series of 180 patients. The reasons for surgery included the presence of high-risk T1‑carcinoma in 5% (9/180) of patients, incomplete resection in less than 1% (1/180), perforation in 1% (2/180]) and appendicitis in less than 1% (1/180).
Postpolypectomy syndrome was reported in 8% (2/25) of patients in the case series of 25 patients. Postpolypectomy syndrome was reported in 2% (4/180) of patients in the unpublished case series of 180 patients.
Infection was reported in 8% (2/25) of patients in the case series of 25 patients. Appendicitis was reported in 1% (2/180) of patients in the unpublished case series of 180 patients.
In addition to safety outcomes reported in the literature, specialist advisers are asked about anecdotal adverse events (events which they have heard about) and about theoretical adverse events (events which they think might possibly occur, even if they have never done so). For this procedure, specialist advisers listed the following anecdotal adverse events: inability to capture the polyp in the snare at resection (necessitating the use of a standard snare). They did not identify any theoretical adverse events that had not previously been reported.