Effect of prior biopsy sampling, tattoo placement, and snare sampling on endoscopic resection of large nonpedunculated colorectal lesions

Dissection-enabled scaffold-assisted resection (DeSCAR): a novel technique for resection of residual or non-lifting GI neoplasia of the colon (with video)

BACKGROUND AND AIMS

As a result of previous manipulation or submucosal invasion, GI lesions referred for EMR frequently have flat areas of visible tissue that cannot be snared. Current methods for treating residual tissue may lead to incomplete eradication or not allow complete tissue sampling for histologic evaluation. Our aim is to describe dissection-enabled scaffold-assisted resection (DeSCAR), a new technique combining circumferential ESD with EMR for removal of superficial non-lifting or residual "islands" with suspected submucosal involvement/fibrosis.

METHODS

From 2015 to 2017, lesions referred for EMR were retrospectively reviewed. Cases were identified where lifting and/or snaring of the lesion was incomplete and the DeSCAR technique was undertaken. Cases were reviewed for location, previous manipulation, rates of successful hybrid resection, and adverse events.

RESULTS

Twenty-nine lesions underwent DeSCAR because of non-lifting or residual "islands" of tissue. Fifty-two percent of the patients were male and 48% were female; average age was 66 years (standard deviation ±9.9 years). Lesions were located in the cecum (n = 10), right side of the colon (n = 12), left side of the colon (n = 4), and rectum (n = 3). Average size was 31 mm (standard deviation ±20.6 mm). Previous manipulation had occurred in 28 of 29 cases (83% biopsy, 34% resection attempt, 52% tattoo). The technical success rate for resection of non-lifting lesions was 100%. There was one episode of delayed bleeding but no other adverse events.

CONCLUSIONS

DeSCAR is a feasible and safe alternative to argon plasma coagulation and avulsion for the endoscopic management of non-lifting or residual GI lesions, providing en bloc resection of tissue for histologic review. Further studies are needed to demonstrate long-term eradication and for comparison with other methods.

Risk Stratification for Covert Invasive Cancer Among Patients Referred for Colonic Endoscopic Mucosal Resection: A Large Multicenter Cohort

BACKGROUND & AIMS

Among patients with large colorectal sessile polyps or laterally spreading lesions, it is important to identify those at risk for submucosal invasive cancer (SMIC). Lesions with overt endoscopic evidence of SMIC are referred for surgery, although those without these features might still contain SMIC that is not visible on endoscopic inspection (covert SMIC). Lesions with a high covert SMIC risk might be better suited for endoscopic submucosal dissection than for endoscopic mucosal resection (EMR). We analyzed a group of patients with large colon lesions to identify factors associated with SMIC, and examined lesions without overt endoscopic high-risk signs to determine factors associated with covert SMIC.

METHODS

We performed a prospective cohort study of consecutive patients referred for EMR of large sessile or flat colorectal polyps or laterally spreading lesions (≥20 mm) at academic hospitals in Australia from September 2008 through September 2016. We collected data on patient and lesion characteristics, outcomes of procedures, and histology findings. We excluded serrated lesions from the analysis of covert SMIC due to their distinct phenotype and biologic features.

RESULTS

We analyzed 2277 lesions (mean size, 36.9 mm) from 2106 patients (mean age, 67.7 years; 53.2% male). SMIC was evident in 171 lesions (7.6%). Factors associated with SMIC included Kudo pit pattern V, a depressed component (0-IIc), rectosigmoid location, 0-Is or 0-IIa+Is Paris classification, non-granular surface morphology, and increasing size. After exclusion of lesions that were obviously SMIC or serrated, factors associated with covert SMIC were rectosigmoid location (odds ratio, 1.87; P = .01), combined Paris classification, surface morphology (odds ratios, 3.96-22.5), and increasing size (odds ratio, 1.16/10 mm; P = .012).

CONCLUSIONS

In a prospective study of 2106 patients who underwent EMR for large sessile or flat colorectal polyps or laterally spreading lesions, we associated rectosigmoid location, combined Paris classification and surface morphology, and increasing size with increased risk for covert malignancy. Rectosigmoid 0-Is and 0-IIa+Is non-granular lesions have a high risk for malignancy, whereas proximally located 0-Is or 0-IIa granular lesions have a low risk. These findings can be used to inform decisions on which patients should undergo endoscopic submucosal dissection, EMR, or surgery. ClinicalTrials.gov, Number: NCT02000141.

Colorectal endoscopic mucosal resection (EMR)

Colonoscopy has the benefit of detecting and treating precancerous adenomatous polyps and thus reduces mortality associated with CRC. Screening colonoscopy is the keystone for prevention of colorectal cancer. Over the last 20 years there has been increased in the management of large colorectal polyps from surgery to endoscopic removal techniques which is less invasive. Traditionally surgical resection was the treatment of choice for many years for larger polyps but colectomy poses significant morbidity of 14-46% and mortality of up to 7%. There are several advantages of endoscopic resection technique over surgery; it is less invasive, less expensive, has rapid recovery, and preserves the normal gut functions. In addition patient satisfaction and efficacy of EMR is higher with minor complications. Thus, this has facilitated the development of advanced resection technique for the treatment of large colorectal polyps called as endoscopic mucosal resection (EMR).

Colorectal endoscopic submucosal dissection: patient selection and special considerations

Endoscopic submucosal dissection (ESD) enables en bloc resection of large complex colorectal superficial neoplastic lesions, resulting in very low rates of local recurrence, high-quality pathologic specimens for accurate histopathologic diagnosis and potentially curative treatment of early adenocarcinoma without resorting to major surgical resection. The safety and efficacy of the technique, which was pioneered in the upper gastrointestinal tract, has been established by the consistently impressive outcomes from expert centers in Japan and some other eastern countries. However, ESD is challenging to perform in the colorectum and there is a significant risk of complications, particularly in the early stages of the learning curve. Early studies from western centers raised concerns about the high complication rates, and the impressive results from Japanese centers were not replicated. As a result, many western endoscopists are skeptical about the role of ESD and few centers have incorporated the technique into their practice. Nevertheless, although the distribution of expertise, referral centers and modes of practice may differ in Japan and western countries, ESD has an important role and can be safely and effectively incorporated into western practice. Key to achieving this is meticulous lesion assessment and selection, appropriate referral to centers with the necessary expertise and experience and application of the appropriate technique individualized to the patient. This review discusses the advantages, risks and benefits of ESD to treat colorectal lesions and the importance of preprocedure lesion assessment and in vivo diagnosis and outlines a pragmatic rationale for appropriate lesion selection as well as the patient, technical and institutional factors that should be considered.

Avulsion is superior to argon plasma coagulation for treatment of visible residual neoplasia during EMR of colorectal polyps (with videos)

BACKGROUND AND AIMS

EMR is used widely for treatment of nonpedunculated colorectal adenomas ≥ 2 cm. Recurrence at the resection site occurs in 10% to 30% of cases.

METHODS

Records of consecutive patients referred for endoscopic resection over a 4-year period were reviewed retrospectively. In the first part of the study period, our routine practice was to use argon plasma coagulation (APC) to treat all visible residual neoplasia after exhaustive attempts at snare resection during EMR. In the second part of the study period, we changed our practice to use avulsion to treat all visible residual neoplasia after exhaustive attempts at snare resection during EMR. We analyzed the effect of this change in practice on recurrence rates after EMR.

RESULTS

Two hundred twenty-three resected lesions were analyzed. Fifty-nine (26%) were treated with en-bloc EMR, 55 (25%) by piecemeal EMR with complete snare removal of all visible neoplasia, 63 (28%) by piecemeal EMR with APC of visible residual neoplasia, and 46 (21%) by piecemeal EMR with avulsion of visible residual neoplasia. There was no significant difference in adverse event rates among the 4 groups. The recurrence rates on follow-up colonoscopy were 4.2%, 3.0%, 59.3%, and 10.3%, respectively. The recurrence rate for patients treated with avulsion was significantly lower than for those treated with APC (odds ratio, .079; P < .001). Multivariate analysis demonstrated that use of avulsion instead of APC was a significant predictor of no recurrence.

CONCLUSIONS

After exhaustive attempts at snare resection during EMR, avulsion is superior to APC for treatment of residual visible neoplasia. Compared with APC, avulsion significantly decreases the recurrence rate without significantly increasing the risk of the procedure.

Endoscopic Mucosal Resection versus Endoscopic Submucosal Dissection for Large Polyps: A Western Colonoscopist's View

To discuss the rationale for the widespread application of endoscopic mucosal resection (EMR) rather than endoscopic submucosal dissection (ESD) in Western centers. In Western centers, EMR is the treatment of choice for most non-pedunculated colorectal adenomas >2 cm in size. EMR is sufficiently effective and safe to be performed without post-procedure hospitalization. Advances in EMR have led to reduced recurrence rates, and recent studies have demonstrated excellent outcomes with endoscopic treatment of recurrent adenomas. While studies from Asia have demonstrated lower recurrence rates with ESD, concern about the higher perforation risk and lengthy procedure time of ESD are two of the barriers preventing widespread adoption of ESD in the West. EMR is likely to continue as the dominant method for the treatment of large colorectal adenomas in Western centers until the limitations of ESD are overcome.

Endoscopic mucosal resection and endoscopic submucosal dissection of large colonic polyps

Almost all large and complex colorectal polyps can now be resected endoscopically. Piecemeal endoscopic mucosal resection (PEMR) is an established technique with fairly low complication risk and good short-term and medium-term outcomes. Several modifications to the basic injection and snare technique have been developed contributing to safer and more complete resections. Delayed bleeding requiring reintervention is the most troublesome complication in 2-7% of patients, particularly in those with comorbidities and large, right-sided polyps. Endoscopic submucosal dissection (ESD) has become popular in Japan and has theoretical advantages over PEMR in providing a complete, en bloc excision for accurate histological staging and reduced local recurrence. These advantages come at the cost of a more complex, expensive and time-consuming procedure with a higher risk of perforation, particularly early in the procedure learning curve. These factors have contributed to the slow adoption of ESD in the West and the challenge to develop new devices and endoscopic platforms that will make ESD easier and safer. Currently, ESD indications are limited to large rectal lesions, in which procedural complications are easily managed, and for colorectal polyps with a high risk of containing tiny foci of early submucosally invasive cancer, whereby ESD may be curative compared with PEMR.

Interval Colorectal Cancer After Colonoscopy: Exploring Explanations and Solutions

There is good evidence that colorectal cancer (CRC) screening has been successful at reducing both CRC incidence and death. Colonoscopy, utilized as either a primary screening tool or a follow-up exam when other screening tests are positive, has significantly contributed to these encouraging trends. However, it is well recognized that colonoscopy is not perfectly sensitive for the detection of neoplasia and that CRC can be diagnosed within a short interval following a colonoscopy that did not detect one. The literature surrounding these cases has rapidly expanded over the last decade. Specifically, studies aimed at understanding the frequency of these events and the likely explanations for their occurrence have been performed. This review will highlight current knowledge around the epidemiology of interval post colonoscopy CRC (PCCRC). The common explanations for these cancers including missed lesions, new lesions, and incompletely resected lesions will be reviewed and their contribution to interval PCCRC estimated. Finally, the relationship of these putative explanations to potential opportunities to prevent interval PCCRC will be explored. Current approaches to prevention largely center on consistent adherence to quality colonoscopy standards. Future approaches include advances in technology to better visualize the colon and adequately resect detected neoplasia. Finally, improvement in training as well as development of a culture of continuous quality improvement will be essential to maximize the benefits of colonoscopy in daily clinical practice.

Outcomes of endoscopic treatment of second recurrences of large nonpedunculated colorectal adenomas

BACKGROUND AND AIMS

Piecemeal endoscopic mucosal resection (EMR) of large nonpedunculated colorectal adenomas is associated with significant recurrence rates. After salvage endoscopic treatment of recurrences, there is a significant rate of second recurrences. There is a paucity of data on the efficacy and safety of continued endoscopic treatment after a second recurrence.

METHODS

Consecutive patients with recurrent adenomas after initial piecemeal EMR of nonpedunculated colorectal adenomas >2 cm were reviewed. We assessed the feasibility, safety and efficacy of continued endoscopic treatment in these patients.

RESULTS

Sixty-four patients with 70 recurrent lesions were identified. All were retreated endoscopically. Follow-up colonoscopy (mean interval 6.4 months) was performed on 62/70 lesions (89 %), and a second recurrence was found in 21/62 (34 %). One patient underwent surgery for a circumferential adenoma of the ileocecal valve. The other 20 lesions were treated endoscopically. Follow-up colonoscopy was performed on 15/20 (75 %) and demonstrated a third recurrence in 3/15 (20 %). One was a deep T1 cancer; curative surgery was performed. The other two patients each had one additional endoscopic treatment and both had no recurrence on subsequent colonoscopy. There were two complications: Both were delayed bleeds after treatment of the first recurrence. A mean of 1.3 endoscopic procedures was required to achieve a cure (range 1-3) for recurrent adenomas after piecemeal EMR.

CONCLUSION

Endoscopic treatment of patients with second recurrences is safe and effective, but is associated with a significant rate of additional recurrences. Continued endoscopic treatment of patients with multiple recurrences is associated with high cure rates, low complication rates and a low risk of progression to malignancy.