From EMR to ESD: a new challenge from Japanese endoscopists

Research on the method of mucosal negative pressure electrocoagulation marking under gastrointestinal endoscopy

With the development of medical equipment technology, minimally invasive surgery has become the core advancement direction in surgical treatment. There are still some issues with mucosal marking and injection under gastrointestinal endoscopy. This paper aims to study a novel negative pressure electrocoagulation marking technique. Using a negative pressure pump in conjunction with a radiofrequency energy emission platform, we compared the effects of conventional electrocoagulation marking and negative pressure electrocoagulation marking using porcine stomachs as experimental subjects. The experimental system includes a negative pressure electrocoagulation platform and a radiofrequency energy emission platform. The experimental materials are fresh porcine stomachs. Electrocoagulation marking of porcine stomach under no negative pressure and negative pressure conditions. An infrared thermal imaging camera was used to measure the temperature. The experimental results showed that the highest average temperature in the no negative pressure group was 78.2 ± 7.6°C, while in the negative pressure group it was 78.1 ± 7.9°C, with no significant difference between the two (p = 0.8557). During subsequent injection tests, the average burst pressure in the no negative pressure group was 66.40 ± 16.96 mmHg, while in the negative pressure group it was 83.48 ± 28.56 mmHg. The negative pressure group had a significantly higher burst pressure (p = 0.0135), indicating that the negative pressure electrocoagulation marking technique can significantly enhance mucosal elevation. The results suggest that the negative pressure electrocoagulation marking technique has great potential for application in gastrointestinal endoscopic surgery. It can improve the safety of the surgery without increasing thermal injury, helping to reduce the incidence of intraoperative complications.

Risk factors for complications of endoscopic submucosal dissection in gastric tumors: analysis of 478 lesions

PURPOSE

Endoscopic submucosal dissection (ESD) technique has facilitated en bloc removal of widely spread lesions from the stomach. This retrospective study aimed to determine factors associated with serious complications of ESD.

METHODS

Between December 2001 and March 2007, we have performed ESD for 478 lesions in 436 patients. We experienced 39 patients with post-operative bleeding and 17 patients with perforation. Risk factors of patients who received ESD in gastric mucosal tumors for complications were evaluated, focusing on resected size, location, scar lesions, operation time, and experience of endoscopists. We evaluated the patients' background characteristics including sex, age, body mass index (kg/m(2)), drug history of anticoagulant, and underlying diseases including cerebrovascular disorder, ischemic heart disease, liver dysfunction, renal dysfunction, hyperuricemia, hypertension and diabetes mellitus.

RESULTS

Multivariate analysis indicated a risk factor for perforation was long operation time. Multivariate analysis indicated a significant risk factor for post-operative bleeding was size of the resected tumor.

CONCLUSIONS

This study indicated risk factors for serious complications of ESD. Large resected tumor size was a risk factor for post-operative bleeding, while long operation time was a risk factor for perforation. Information regarding operation risk factors should be useful for planning strategies for ESD.

Selection of cap size in endoscopic submucosal resection with cap aspiration for rectal carcinoid tumors

BACKGROUND

Small rectal carcinoid tumors (<or=1 cm in diameter) can be treated by endoscopic resection, but complete resection may be difficult if tumors are located in the deep submucosal layer. This study was performed to identify the clinicopathologic factors affecting the complete resection of small rectal carcinoid tumors, using the endoscopic submucosal resection with cap aspiration technique (ESMR-C).

MATERIALS AND METHODS

Forty-one consecutive patients with 42 rectal carcinoid tumors who underwent ESMR-C from October 2003 to November 2006 were assessed. Complete resection was defined as a clean margin that was free of tumor invasion at the lateral and inferior edges.

RESULTS

The rate of complete tumor removal by ESMR-C was 85.7% and no complications occurred. The tumor size, location, and method of resection did not significantly affect the completeness of resection. Univariate analysis showed that the rate of complete resection was significantly higher when using 19.2-mm, compared with 13.9-mm, caps (96.0 vs. 70.6%; P = 0.032). Multivariate analysis showed that the cap size was an independent factor predicting the completeness of resection.

CONCLUSION

The use of large-sized caps increases the completeness of the resection of rectal carcinoid tumors when using ESMR-C.

Clinical outcomes of endoscopic submucosal dissection (ESD) for treating early gastric cancer: comparison with endoscopic mucosal resection after circumferential precutting (EMR-P)

BACKGROUND

To achieve en bloc resection for large lesions, endoscopic mucosal resection after circumferential precutting and endoscopic submucosal dissection techniques have been developed.

AIM

To compare endoscopic submucosal dissection with endoscopic mucosal resection after circumferential precutting in terms of the clinical efficacy and safety.

PATIENTS AND METHODS

346 consecutive patients underwent their first endoscopic mucosal resection after circumferential precutting (103 patients) or endoscopic submucosal dissection (243 patients) for early gastric cancer and their clinical outcomes were compared.

RESULTS

For early gastric cancer >or=20mm endoscopic submucosal dissection group demonstrated significantly higher en bloc resection and en bloc plus R0 resection rate compared with endoscopic mucosal resection after circumferential precutting group. For early gastric cancer with size of 10-19 mm, endoscopic submucosal dissection group also showed significantly higher en bloc resection rate. For early gastric cancer <20mm, however, en bloc plus R0 resection rate for endoscopic mucosal resection after circumferential precutting group was comparable to that for endoscopic submucosal dissection group. In case of R0 resection of intramucosal differentiated cancer, neither group showed local recurrence during the median 29 and 17 months of follow-up. Two groups did not show significant difference in the bleeding or perforation rates.

CONCLUSION

For early gastric cancer <20mm endoscopic mucosal resection after circumferential precutting may be considered as an alternative choice to endoscopic submucosal dissection. However, for early gastric cancer >or=20mm endoscopic submucosal dissection should be considered as the first choice for treating early gastric cancer.

Feasibility of electrocautery snaring as the final step of endoscopic submucosal dissection for stomach epithelial neoplasms

BACKGROUND

Endoscopic submucosal dissection (ESD) is a novel endoluminal technique that permits the resection of gastric neoplasms.

AIM

To analyse the feasibility of snaring as the final step of ESD.

PATIENTS AND METHODS

One hundred and ninety-nine consecutive gastric neoplasms resected by four ESD experts from January 2004 to May 2007 were investigated. Forty-five (22.6%) were finally resected finally using a snare. Rates of en bloc resection, complete (R0 plus en bloc) resection, mean operation time, and complications were assessed between the snaring and the non-snaring groups.

RESULTS

En bloc resection rate was significantly lower and delayed bleeding rate was significantly higher in the snaring group than in the non-snaring group (91.1% [41/45] vs. 100% [154/154], 11.1% [5/45] vs. 1.9% [3/154], respectively), although complete resection rate (86.7% [39/45] vs. 92.9% [143/154]) and mean operation time (70.2 min vs. 75.8 min) were not significantly different between the two groups. Six perforation cases (3 [6.7%] in the snaring group, 3 [1.9%] in the non-snaring group) were observed, but snaring did not lead to perforation in any case. When the subjects were divided into small (< or = 2 cm) and large (> 2 cm) tumours, en bloc resection rate in large tumours was still significantly different between the groups (76.9% [10/13] vs. 100% [67/67]), whereas in small tumours it was no longer significantly different (96.9% [31/32] vs. 100% [87/87]).

CONCLUSIONS

Snaring may facilitate successful ESD for smaller tumours, but multiple-piece resection should be taken into account especially for larger tumours.

Endoscopic resection of superficial gastrointestinal tumors

Therapeutic endoscopy plays a major role in the management of gastrointestinal (GI) neoplasia. Its indications can be generalized into four broad categories; to remove or obliterate neoplastic lesion, to palliate malignant obstruction, or to treat bleeding. Only endoscopic resection allows complete histological staging of the cancer, which is critical as it allows stratification and refinement for further treatment. Although other endoscopic techniques, such as ablation therapy, may also cure early GI cancer, they can not provide a definitive pathological specimen. Early stage lesions reveal low frequency of lymph node metastasis which allows for less invasive treatments and thereby improving the quality of life when compared to surgery. Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are now accepted worldwide as treatment modalities for early cancers of the GI tract.