How to deal with large colorectal polyps: snare, endoscopic mucosal resection, and endoscopic submucosal dissection; resect or refer?

An Asymptomatic Patient with Colonic Leiomyoma

Subepithelial lesions (SELs) originating from muscularis mucosae of the colon are very rare findings on endoscopy. Appropriate management of SELs involves making a correct diagnosis and estimating their malignant potential. In this case study, a 58-year-old Saudi man presented with a small, 8-mm sigmoid polyp during screening colonoscopy. The polyp was removed by hot snare polypectomy and sent to pathology laboratory. Report showed an unremarkable colonic mucosa and underlying well-circumscribed submucosal lesion composed of monotonous spindle cells. Immunohistochemical (IHC) analysis ruled out CD117-/DOG1-positive GIST and confirmed the lesion as leiomyomatous polyp. Colonic leiomyomas are usually benign and often asymptomatic and discovered during CRC screening procedures. Diagnosis is made on histology/IHC analysis since endoscopically they might be indistinguishable from other SELs. Conventional polypectomy is an appropriate treatment for small colonic leiomyoma and these benign lesions typically do not recur.

Endoscopic Management of Complex Colorectal Polyps: Current Insights and Future Trends

Most colorectal cancers arise from adenomatous polyps and sessile serrated lesions. Screening colonoscopy and therapeutic polypectomy can potentially reduce colorectal cancer burden by early detection and removal of these polyps, thus decreasing colorectal cancer incidence and mortality. Most endoscopists are skilled in detecting and removing the vast majority of polyps endoscopically during a routine colonoscopy. Polyps can be considered “complex” based on size, location, morphology, underlying scar tissue, which are not amenable to removal by conventional endoscopic polypectomy techniques. They are technically more challenging to resect and carry an increased risk of complications. Most of these polyps were used to be managed by surgical intervention in the past. Rapid advancement in endoscopic resection techniques has led to a decreasing role of surgery in managing these complex polyps. These endoscopic resection techniques do require an expert in the field and advanced equipment to perform the procedure. In this review, we discuss various advanced endoscopic techniques for the management of complex polyps.

ASGE review of adverse events in colonoscopy

Colonoscopy is the most commonly performed endoscopic procedure and overall is considered a low-risk procedure. However, adverse events (AEs) related to this routinely performed procedure for screening, diagnostic, or therapeutic purposes are an important clinical consideration. The purpose of this document from the American Society for Gastrointestinal Endoscopy's Standards of Practice Committee is to provide an update on estimates of AEs related to colonoscopy in an evidence-based fashion. A systematic review and meta-analysis of population-based studies was conducted for the 3 most common and important serious AEs (bleeding, perforation, and mortality). In addition, this document includes an updated systematic review and meta-analysis of serious AEs (bleeding and perforation) related to EMR and endoscopic submucosal dissection for large colon polyps. Finally, a narrative review of other colonoscopy-related serious AEs and those related to specific colonic interventions is included.

Cost Effectiveness of Endoscopic Resection vs Transanal Resection of Complex Benign Rectal Polyps

BACKGROUND & AIMS

Complex benign rectal polyps can be managed with transanal surgery or with endoscopic resection (ER). Though the complication rate after ER is lower than transanal surgery, recurrence is higher. Patients lost to follow up after ER might therefore be at increased risk for rectal cancer. We evaluated the costs, benefits, and cost effectiveness of ER compared to 2 surgical techniques for removing complex rectal polyps, using a 50-year time horizon-this allowed us to capture rates of cancer development among patients lost from follow-up surveillance.

METHODS

We created a Markov model to simulate the lifetime outcomes and costs of ER, transanal endoscopic microsurgery (TEM), and transanal minimally invasive surgery (TAMIS) for the management of a complex benign rectal polyp. We assessed the effect of surveillance by allowing a portion of the patients to be lost to follow up. We calculated the cost, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio or each intervention over a 50-year time horizon.

RESULTS

We found that TEM was slightly more effective than TAMIS and ER (TEM, 19.54 QALYs; TAMIS, 19.53 QALYs; and ER, 19.53 QALYs), but ER had a lower lifetime discounted cost (ER cost $7161, TEM cost $10,459, and TAMIS cost $11,253). TEM was not cost effective compared to ER, with an incremental cost-effectiveness ratio of $485,333/QALY. TAMIS was dominated by TEM. TEM became cost effective when the mortality from ER exceeded 0.63%, or if the loss to follow up rate exceeded 25.5%.

CONCLUSIONS

Using a Markov model, we found that ER, TEM, and TAMIS have similar effectiveness, but ER is less expensive, in management of benign rectal polyps. As the rate of loss to follow up increases, transanal surgery becomes more effective relative to ER.

A novel technique of endoscopic submucosal dissection for circumferential ileocecal valve adenomas with terminal ileum involvement: the "doughnut resection" (with videos)

BACKGROUND

Ileocecal valve (ICV) lesions are difficult to resect endoscopically and patients are often referred for laparoscopic colectomy. ICV involvement has been shown to be related to technical failure and tumor recurrence after endoscopic mucosal resection (EMR) and represents a challenge for endoscopic submucosal dissection (ESD). Few publications have focused specifically on endoscopic management of ICV lesions.

METHODS

We developed a novel ESD technique, the "doughnut resection," for circumferential ICV adenomas with terminal ileum involvement. Two circumferential mucosal incisions are performed, one in the ileum and the other in the cecum, followed by submucosal dissection of the disk of tissue between the two incisions around a guiding stent placed across the valve that helps guide the dissection as it crosses the valve orifice. The lesion is removed en bloc in the shape of a "doughnut" with two concentric assessable lateral margins. The underwater ESD technique and a gastroscope were used to facilitate the resection.

RESULTS

Seven patients received the doughnut resection. The median patient age was 67 years. All patients had prior biopsy and three had prior endoscopic resection (1-6 times). The median specimen diameter was 4.5 cm (range 3-8). All resections were en bloc and R0. There was no perforation, delayed bleeding, or other clinically significant adverse events. After a median follow-up of 21 months (range 12-32), there was no tumor recurrence.

CONCLUSION

The "doughnut resection" is a feasible, safe, and effective method to remove circumferential ICV lesions endoscopically even for patients with multiple prior tumor manipulations.

Colorectal polyp risk is linked to an elevated level of homocysteine

Several studies have reported an association between levels of folate, homocysteine, and vitamin B₁₂ and the risk of colorectal polyps. Here, our aim is to examine the possible effect of folate, homocysteine, and vitamin B₁₂ levels on the risk of colorectal polyps by means of meta-analysis based quantitative synthesis. According to our inclusion/exclusion criteria, a total of 13 case–control studies were enrolled. The P-value of the association test, standard mean difference (SMD), and 95% confidence interval (CI) were calculated. Pooled analysis data showed a negative correlation between the risk of colorectal polyps and the levels of serum folate, red blood cell (RBC) folate, or vitamin B₁₂ (all P>0.05). Nevertheless, for homocysteine level, we also observed a statistically significant difference between cases and controls in the overall and subgroup analysis of hospital-based control (HB), population-based control (PB), Chinese, Caucasian, or Asian (all P<0.05, SMD > 0). We found that increased levels of homocysteine may be statistically and significantly related to the risk of colorectal polyps.