Indications and outcomes of endoscopic resection for non-pedunculated colorectal lesions: A narrative review

Endoscopic Submucosal Dissection, Endoscopic Mucosal Resection, and Transanal Minimally Invasive Surgery for the Management of Rectal and Anorectal Lesions: A Narrative Review

Endoscopic submucosal dissection (ESD), endoscopic mucosal resection (EMR), and transanal minimally invasive surgery (TAMIS) are modern techniques that now play a crucial role in the treatment of colorectal lesions. ESD is a minimally invasive endoscopic procedure that allows for the resection of lesions of any size in a single piece, with clear advantages regarding oncological outcomes and recurrences. However, it is a complex technique, requiring high endoscopic skills, expertise, and specialized training, with higher rates of adverse events expected compared with EMR. EMR is another endoscopic technique used to remove superficial gastrointestinal tumors, particularly those that are limited to the mucosal layer. It is a faster and more accessible procedure, with fewer adverse events, although it only allows for an en-bloc resection of lesions measuring 15-20 mm. TAMIS is a minimally invasive surgical technique used to remove rectal tumors, involving the insertion of a single-port device through the anus, allowing for a better visualization and removal of the tumor with minimal disruption. This article reviews the current applications and evidence regarding these techniques, in search for the most adequate treatment for the removal of lesions in the rectum and anorectal junction, as these locations possess distinct characteristics that demand a more specific approach.

Factors affecting the quality of bowel preparation for colonoscopy in hard-to-prepare patients: Evidence from the literature

Adequate bowel cleansing is critical for a high-quality colonoscopy because it affects diagnostic accuracy and adenoma detection. Nevertheless, almost a quarter of procedures are still carried out with suboptimal preparation, resulting in longer procedure times, higher risk of complications, and higher likelihood of missing lesions. Current guidelines recommend high-volume or low-volume polyethylene glycol (PEG)/non-PEG-based split-dose regimens. In patients who have had insufficient bowel cleansing, the colonoscopy should be repeated the same day or the next day with additional bowel cleansing as a salvage option. A strategy that includes a prolonged low-fiber diet, a split preparation regimen, and a colonoscopy within 5 h of the end of preparation may increase cleansing success rates in the elderly. Furthermore, even though no specific product is specifically recommended in the other cases for difficult-to-prepare patients, clinical evidence suggests that 1-L PEG plus ascorbic acid preparation are associated with higher cleansing success in hospitalized and inflammatory bowel disease patients. Patients with severe renal insufficiency (creatinine clearance < 30 mL/min) should be prepared with isotonic high volume PEG solutions. Few data on cirrhotic patients are currently available, and no trials have been conducted in this population. An accurate characterization of procedural and patient variables may lead to a more personalized approach to bowel preparation, especially in patients undergoing resection of left colon lesions, where intestinal preparation has a poor outcome. The purpose of this review was to summarize the evidence on the risk factors influencing the quality of bowel cleansing in difficult-to-prepare patients, as well as strategies to improve colonoscopy preparation in these patients.

A systematic review and meta-analysis of endoscopic mucosal resection vs endoscopic submucosal dissection for colorectal sessile/non-polypoid lesions

BACKGROUND

Current international guidelines strongly advise endoscopic submucosal dissection (ESD) instead of endoscopic mucosal resection (EMR) for the endoscopic resection of sessile colorectal tumours >20 mm.

AIMS

To compare the safety and efficacy of EMR and ESD for treating large non-invasive colorectal lesions.

MATERIAL AND METHODS

We performed a systematic review using electronic databases (MEDLINE/PubMed, EMBASE, and Cochrane Library) on February 21st, 2021 and a meta-analysis to assess en-bloc and R0 rates, and related adverse events.

RESULTS

Twenty-four studies were included, comparing 3,424 ESD and 5,122 EMR procedures. The en-bloc resection rate was 90.8% in the ESD and 33.0% in the EMR group (p < .001). The R0 resection rate was 85.0% in the ESD and 64.6% in the EMR group (p = .005). The rate of perforation was 5.1% in the ESD and 1.67% in the EMR group (p < .001). The bleeding rate was 4.3% in the ESD and 3.6% in the EMR group (p = .008). The overall need for surgery, including oncologic reasons and complications, was 5.9% in the ESD and 3.1% in the EMR group (p < .001).

CONCLUSIONS

ESD for large non-pedunculated colorectal lesions allows a higher rate of R0 resections than EMR, at the cost of a higher perforation rate and the need for additional surgery.