Endoscopic treatment of sessile rectal adenomas: comparison of Nd:YAG laser therapy and injection-assisted piecemeal polypectomy

Extended endoscopic mucosal resection does not reduce recurrence compared with standard endoscopic mucosal resection of large laterally spreading colorectal lesions

BACKGROUND AND AIMS

Effective interventions to prevent residual and/or recurrent adenoma (RRA) after EMR of large sessile and laterally spreading colorectal lesions (LSL) are yet to be determined. RRA may occur due to inconspicuous adenoma at the EMR margin. We aimed to determine the efficacy and safety of extended EMR (X-EMR) compared with standard EMR (S-EMR).

METHODS

A single-center post hoc analysis of LSL ≥20 mm referred for treatment was performed. S-EMR was the standard sequential inject and resect method including a 1-mm to 2-mm margin of normal mucosa around the lesion. With X-EMR, at least a 5-mm margin of normal mucosa was excised. Patient and lesion characteristics and procedural outcomes were recorded. The primary endpoint was RRA at first surveillance colonoscopy at 4 months.

RESULTS

Between January 2009 and May 2011, 471 lesions (mean size, 37.9 mm) in 424 patients were resected by S-EMR, and between January 2012 and December 2013, 448 lesions (mean size, 39.1 mm) in 396 patients were resected by X-EMR. Resection was successful in 92.3% and 92.6% of referred lesions in the S-EMR and X-EMR groups, respectively (P = .978). X-EMR was independently associated with a higher risk of intraprocedural bleeding (IPB) (odds ratio, 3.1; 95% confidence interval [CI], 2.0-5.0; P < .001) but not other adverse events. RRA was present in 39 of 333 patients (11.7%) and 30 of 296 patients (10.1%) in the S-EMR and X-EMR groups, respectively (P = .15). X-EMR was not related to recurrence (hazard ratio, 0.8; 95% CI, 0.5-1.3; P = .399).

CONCLUSIONS

X-EMR does not reduce RRA and increases the risk of IPB compared with S-EMR. Alternative methods for the prevention of RRA are required.

Improved Techniques for Endoscopic Mucosal Resection (EMR) in Colorectal Adenoma

Background

Endoscopic therapy of colorectal adenomas and early cancers is a standard method. Besides oncological criteria, the method is limited by polyp location, size, and texture.

Method

Based on the current literature, technical modifications and developments in endoscopic mucosal resection are described.

Results

Numerous approaches exist to improve the conditions of resection, including optimisation of mucosal elevation and modification of techniques, tools, and devices.

Conclusion

Endoscopic therapy of sessile and flat colorectal polyps remains a challenge. Some of the presented modifications can help to address this challenge.

Local recurrence after endoscopic resection of colorectal tumors

BACKGROUND AND AIMS

Local recurrence frequently occurs after endoscopic resection of large colorectal tumors. However, appropriate intervals for surveillance colonoscopy to assess local recurrence after endoscopic resection have not been clarified. The aim of the present study was to determine local recurrence rates following en-bloc and piecemeal endoscopic resection and establish appropriate surveillance colonoscopy intervals based on retrospective analysis of local recurrences.

MATERIALS AND METHODS

A total of 461 patients with 572 > or = 10-mm lesions underwent endoscopic resection and follow-up. We retrospectively compared local recurrence rates on lesion size, macroscopic type, and histological type after en-bloc resection (440 lesions) and piecemeal resection (132 lesions). Cumulative local recurrence rates were analyzed using the Kaplan-Meier method.

RESULTS

Local recurrence occurred for 34 lesions (5.9%). Local recurrence rates for the en-bloc and piecemeal groups was 0.7% (3/440) and 23.5% (31/132), respectively (P < 0.001). The difference between the two groups was distinct in terms of lesion size, macroscopic type, and histological type. Of the 34 local recurrences, 32 were treated endoscopically and two cases required additional surgery. The 6-, 12-, and 24-month cumulative local recurrence rate of the en-bloc group was 0.24%, 0.49%, and 0.81%. Then the 6-, 12-, and 24-month cumulative local recurrence rate for the piecemeal group was 18.4%, 23.1%, and 30.7%.

CONCLUSION

Local recurrence occurred more frequently after piecemeal resection than en-bloc resection. However, almost all cases of local recurrences could be cured by additional endoscopic resection, so piecemeal resection can be acceptable treatment.

Treatment with argon plasma coagulation reduces recurrence after piecemeal resection of large sessile colonic polyps: a randomized trial and recommendations

BACKGROUND

Recurrence is frequent after piecemeal snare resection of large sessile colorectal polyps. The aim of this study was to evaluate the safety and efficacy of argon plasma coagulation (APC) in preventing recurrence when applied to the edge and base of the polypectomy site after apparently complete piecemeal resection.

METHODS

Patients with large (>1.5 cm) sessile polyps removed by piecemeal snare cautery were placed into 2 groups. The first consisted of patients with polyps believed by the endoscopist to be completely excised. These patients were randomized to either no further therapy (control) or to APC of the rim and any residual mucosal or submucosal tissue in the base of the polypectomy site. The second group comprised patients in whom polyps, as judged by the endoscopist, were incompletely excised by snare polypectomy; APC was routinely applied without randomization to all visible remaining adenomatous tissue. Follow-up colonoscopy was performed within 3 months and 1 year; biopsy specimens were taken routinely from the resection site and further polypectomy was performed as indicated.

RESULTS

There were fewer recurrences after APC in the randomized group (1/10 APC, 7/11 no APC; p = 0.02). In the group with initial incomplete snare polypectomy, recurrence was detected at 3 months in 6 of 13 despite APC. One patient was hospitalized with abdominal pain and minor rectal bleeding but required no intervention. There were no other episodes of significant late bleeding caused by piecemeal polypectomy. One patient was referred for surgery after unsuccessful endoscopic management.

CONCLUSIONS

In patients with apparent complete endoscopic snare resection of large adenomas, postpolypectomy application of APC reduces adenomatous recurrence.

Large sessile colonic adenomas: use of argon plasma coagulator to supplement piecemeal snare polypectomy

BACKGROUND

Residual adenoma is frequently found at the site of endoscopically resected large sessile adenomas on follow-up examination. We evaluated the efficacy of a thermal energy source, the argon plasma coagulator, to destroy visible residual adenoma after piecemeal resection of sessile polyps.

METHODS

Seventy-seven piecemeal polypectomies with or without the use of argon plasma coagulator were analyzed retrospectively. All polyps were sessile, 20 mm or greater in size. The results from three groups of patients were compared. The study group was composed of patients who had visible residual adenoma after piecemeal polypectomy and had the base of the polypectomy site treated with the argon plasma coagulator. The first comparison group consisted of patients who underwent standard piecemeal polypectomy in whom the colonoscopist thought that all adenomatous tissue was removed and no further treatment was necessary. The second comparison group included patients in whom visible residual adenoma was left at the base after piecemeal resection of large adenomas. Follow-up colonoscopy was performed approximately 6 months after the initial procedure to check for recurrent/residual adenomatous tissue.

RESULTS

The argon plasma coagulator was used after 30 piecemeal polypectomies in an attempt to eradicate visible residual adenomatous tissue; at follow-up, 50% of these cases had complete eradication of adenoma. The group in whom all visible tumor was removed by piecemeal polypectomy alone had an adenoma eradication rate of 54% on follow-up colonoscopy. In the patients in whom visible residual adenoma was left at the site the recurrence rate was 100% on the follow-up examination. Bleeding necessitating endoscopic therapy occurred once (3.3%) in the argon plasma coagulator group; there were four (12.5%) bleeding episodes and one (3.1%) confined retroperitoneal perforation in the complete piecemeal polypectomy group and no complications in the group in which polypectomy was incomplete.

CONCLUSIONS

Argon plasma coagulator ablation of residual adenomatous tissue at the polypectomy base is safe and useful. It helps to complete the eradication of large sessile polyps when there is visible evidence of residual polyp.

Correlation between macroscopic morphologic features and malignant potential of colorectal sessile adenomas

PURPOSE AND METHODS

To clarify malignant potential of colorectal sessile adenomas, we investigated 46 colorectal sessile adenomas surgically resected from 44 patients. Lesions were divided into three types according to their macroscopic morphologic features: nodular-type (19 adenomas), villous-type (7), and creeping-type (20). Clinicopathologic features were investigated and compared among these three types.

RESULTS

Frequency of focal carcinoma in the nodular-type, villous-type, and creeping-type adenoma was 37, 29, and 55 percent, respectively. Frequency of submucosal invasion in these three types were 11, 14, and 20 percent, respectively. Irrespective of the type, large lesions (> 3 cm) tended to have a higher frequency of submucosal invasion than did smaller ones (60 vs. 20 percent; P = 0.063). Large creeping-type adenomas (> 3 cm) had a definitely higher frequency of submucosal invasion than smaller ones (36 vs. 0 percent; P < 0.05). Lymphatic or vascular invasion of carcinoma was present only in the lesion with submucosal invasion: 5 percent in the nodular-type; 14 percent in the villous-type; 20 percent in the creeping-type. Lymph node metastasis was present only in the creeping-type lesion.

CONCLUSIONS

The large creeping-type adenomas (> 3 cm) have a definitely high frequency of submucosal invasive carcinoma. Endoscopic polypectomy or local resection may be adequate for most sessile adenomas. However, we recommend segmental resection of the colon with regional lymph node dissection for a creeping-type adenoma that is larger than 3 cm because of increased risk of submucosal carcinomatous invasion and lymph node involvement.