EMR of upper GI lesions when using a novel soft, irrigation, prelooped hood

Early Gastric Cancer: Current Advances of Endoscopic Diagnosis and Treatment

Endoscopy is a major method for early gastric cancer screening because of its high detection rate, but its diagnostic accuracy depends heavily on the availability of endoscopic instruments. Many novel endoscopic techniques have been shown to increase the diagnostic yield of early gastric cancer. With the improved detection rate of EGC, the endoscopic treatment has become widespread due to advances in the instruments available and endoscopist's experience. The aim of this review is to summarize frequently-used endoscopic diagnosis and treatment in early gastric cancer (EGC).

Endoscopic treatment for early gastric cancer

Gastric cancer remains one of the most common causes of cancer death. However the proportion of early gastric cancer (EGC) at diagnosis is increasing. Endoscopic treatment for EGC is actively performed worldwide in cases meeting specific criteria. Endoscopic mucosal resection can treat EGC with comparable results to surgery for selected cases. Endoscopic submucosal dissection (ESD) increases the en bloc and complete resection rates and reduces the local recurrence rate. ESD has been performed with expanded indication and is expected to be more widely used in the treatment of EGC through the technological advances in the near future. This review will describe the techniques, indications and outcomes of endoscopic treatment for EGC.

Development of a novel endoscopic manipulation system: The Endoscopic operation robot

AIM: To develop and evaluate the endoscopic operation robot (EOR). The EOR is a robot system designed specifically for remote manipulation of the scope during gastrointestinal endoscopy by a seated endoscopist.

METHODS: Total colonoscopy examinations using a colonoscopy training model were performed compared conventional insertion by manual manipulation and remote-controlled insertion, using the EOR. The author investigated the time taken for each of the 50 examinations.

RESULTS: The median insertion time (in minutes) for each 10 examinations (EOR vs manual manipulation) was 73.70 ± 25.37 vs 3.77 ± 1.34 in the first group, 38.40 ± 6.24 vs 3.40 ± 0.97 in the second group, 27.6 ± 4.01 vs 2.70 ± 0.95 in the third group, 23.8 ± 3.65 vs 3.10 ± 0.88 in the fourth group, and 22.9 ± 5.02 vs 2.60 ± 1.08 in the fifth group.

CONCLUSION: The study suggested the possibility of the clinical application of the EOR.

Advantages of endoscopic submucosal dissection versus endoscopic oblique aspiration mucosectomy for superficial esophageal tumors

BACKGROUND AND AIM

In the treatment of superficial esophageal tumors (SET), en bloc histologically-complete resection reduces the risk of local recurrence. Endoscopic oblique aspiration mucosectomy (EOAM) and endoscopic submucosal dissection (ESD) have been applied to resect SET. The aim of this study was to retrospectively determine whether ESD is more advantageous than EOAM for SET.

METHODS

In the present study, there was a total of 122 patients in whom 162 SET were resected endoscopically at Hiroshima University Hospital. EOAM (83 lesions/63 patients) or ESD (79 lesions/59 patients) was performed. En bloc histologically-complete resection rates, operation time, complications, and the local recurrence rate were studied.

RESULTS

In SET > 20 mm, the en bloc histologically-complete resection rate was significantly higher with ESD than with EOAM (94% vs 42%, P < 0.001). In SET of 16-20 mm, the rate tended to be higher with ESD than with EOAM (100% vs 81%, P = 0.08). In SET < 15 mm, the rates did not differ significantly between groups. The average operation time was significantly longer for ESD than for EOAM, regardless of tumor size (49.7 ± 33.0 min vs 19.1 ± 6.1 min, P < 0.001). Complication rates did not differ significantly between groups. The local recurrence rate was significantly lower with ESD than with EOAM (0%, mean observation period: 18.9 months vs 9%, mean observation period: 30.7 months, P = 0.03).

CONCLUSION

Although increased operation time with ESD remains problematic, SET > 15 mm should be treated with ESD to reduce local recurrence. In lesions ≤ 15 mm, EOAM might be preferable, especially in high-risk patients.

Is endoscopic forceps biopsy enough for a definitive diagnosis of gastric epithelial neoplasia?

BACKGROUND AND AIM

Endoscopic forceps biopsy (EFB) as the primary histological diagnosis of gastric epithelial neoplasia (GEN) is debated in the era of endoscopic resection (ER). Our aim was to investigate the diagnostic reliability of EFB in patients with GEN compared with ER specimens as the reference standard for the final diagnosis in a large consecutive series.

METHODS

This was a cross-sectional retrospective study at a tertiary-referral center. A total of 354 consecutive patients with 397 GENs underwent ER (endoscopic mucosal resection or endoscopic submucosal dissection). Discrepancy rates between the histological results from EFB and ER specimens were assessed. Discrepancies that could affect patient outcome or clinical care were considered major.

RESULTS

The overall histological discrepancy rate between EFB and ER specimens was 44.5% (95% confidence interval [CI], 39.7-49.5%) among the enrolled patients. The overall discrepancy rate was significantly higher in the intraepithelial neoplasia (IEN) group than in the carcinoma group (49.8% vs 25.6%, P < 0.001). The major discrepancy rate was also significantly higher in the IEN group than in the carcinoma group (36.6% vs 7.0%, P < 0.001). In subgroup analysis of the IEN group, a major histological discrepancy rate of 33.6% (70/208) for low-grade and 42.7% (44/103) for high-grade IEN was found, respectively.

CONCLUSIONS

Endoscopic forceps biopsy was insufficient for a definitive diagnosis and therapeutic planning in patients with GEN. ER should be considered as not only definitive treatment but also a procedure for a precise histological diagnosis for lesions initially assessed as GEN by forceps biopsy specimens.

Endoscopic mucosal resection and endoscopic submucosal dissection for early gastric cancer: Current and original devices

Compared with endoscopic submucosal dissection (ESD), endoscopic mucosal resection (EMR) is easier to perform and requires less time for treatment. However, EMR has been replaced by ESD, because achieving en bloc resection of specimens > 20 mm in diameter is difficult with EMR. The technique of ESD was introduced to resect large specimens of early gastric cancer in a single piece. ESD can provide precise histological diagnosis and can also reduce the rate of recurrence, but has a high level of technical difficulty, and is consequently associated with a high rate of complications, a need for advanced endoscopic techniques, and a lengthy procedure time. To overcome disadvantages in both EMR and ESD, various advances have been made in submucosal injections, knives, other accessories, and in electrocoagulation systems.

Endoscopic resection of early gastric cancer

The purpose of this review is to examine recent advances in the techniques and technologies of endoscopic resection of early gastric cancer (EGC). Endoscopic mucosal resection (EMR) of EGC, with negligible risk of lymph node metastasis, is a standard technique in Japan and is increasingly becoming accepted and regularly used in Western countries. EMR is a minimally invasive technique which is safe, convenient, and efficacious; however, it is insufficient when treating larger lesions. The evidence suggests that difficulties with the correct assessment of depth of tumor invasion lead to an increase in local recurrence with standard EMR when lesions are larger than 15 mm. A major factor contributing to this increase in local recurrence relates to lesions being excised piecemeal due to the technical limitations of standard EMR. A new development in endoscopic techniques is to dissect directly along the submucosal layer -- a procedure called endoscopic submucosal dissection (ESD). This allows the en-bloc resection of larger lesions. ESD is not necessarily limited by lesion size and it is predicted to replace conventional surgery in dealing with certain stages of ECG. However, it still has a higher complication rate when compared to standard EMR, and it requires high levels of endoscopic skill and experience. Endoscopic techniques, indications, pathological assessment, and methods of endoscopic resection of EGC need to be established for carrying out appropriate treatment and for the collation of long-term outcome data.

Endoscopic resection of early gastric cancer

The purpose of this review is to examine recent advances in the techniques and technologies of endoscopic resection of early gastric cancer (EGC). Endoscopic mucosal resection (EMR) of EGC, with negligible risk of lymph node metastasis, is a standard technique in Japan and is increasingly becoming accepted and regularly used in Western countries. EMR is a minimally invasive technique which is safe, convenient, and efficacious; however, it is insufficient when treating larger lesions. The evidence suggests that difficulties with the correct assessment of depth of tumor invasion lead to an increase in local recurrence with standard EMR when lesions are larger than 15 mm. A major factor contributing to this increase in local recurrence relates to lesions being excised piecemeal due to the technical limitations of standard EMR. A new development in endoscopic techniques is to dissect directly along the submucosal layer -- a procedure called endoscopic submucosal dissection (ESD). This allows the en-bloc resection of larger lesions. ESD is not necessarily limited by lesion size and it is predicted to replace conventional surgery in dealing with certain stages of ECG. However, it still has a higher complication rate when compared to standard EMR, and it requires high levels of endoscopic skill and experience. Endoscopic techniques, indications, pathological assessment, and methods of endoscopic resection of EGC need to be established for carrying out appropriate treatment and for the collation of long-term outcome data.

Endoscopic submucosal dissection of early gastric cancer

The purpose of this review was to examine a remarkable technical advance regarding the indications for and the technique of endoscopic resection of early gastric cancer. Endoscopic mucosal resection (EMR) of early gastric cancer with no risk of lymph node metastasis has been a standard technique in Japan, probably owing to the high incidence of gastric cancer in Japan and the fact that more than half of Japanese gastric cancer cases are diagnosed at an early stage. Very recently, several EMR techniques have become increasingly accepted and regularly used in Western countries. Although these minimally invasive techniques are safe, convenient, and efficacious, they are unsuitable for large lesions in particular. Difficulty in correctly assessing the depth of tumor invasion and an increase in local recurrence when standard EMR procedures are used have been reported in cases of large lesions, because such lesions are often resected piecemeal owing to the technical limitations of standard EMR. A new development in therapeutic endoscopy, called endoscopic submucosal dissection (ESD), allows the direct dissection of the submucosa, and large lesions can be resected en bloc. ESD is not limited by resection size and is expected to replace surgical resection. However, it is still associated with a higher incidence of complications than standard EMR procedures and requires a high level of endoscopic skill. The endoscopic indications, techniques, and management of complications of ESD for early gastric cancer for properly carrying out established therapeutic endoscopy are described.

Endoscopic resection of early gastric cancer: the Japanese perspective

PURPOSE OF REVIEW

To examine recent advances in the techniques and technologies of endoscopic resection of early gastric cancer.

RECENT FINDINGS

Endoscopic mucosal resection of early gastric cancer with no risk of lymph node metastasis has been a standard technique in Japan and is increasingly becoming accepted and regularly used in Western countries. Though this minimally invasive technique is a safe, convenient and efficacious method, it is insufficient for larger lesions. Difficulties in correctly assessing the depth of tumour invasion and increases in local recurrence by standard endoscopic mucosal resection have been reported in lesions larger than 15 mm. This is because such lesions are often resected piecemeal due to the technical limitation of standard endoscopic mucosal resection. New developments in endoscopic resection techniques to dissect the submucosa directly, called endoscopic submucosal dissection, allows resections of larger lesions en bloc. There are no limitations in resection size in endoscopic submucosal dissection, which is expected to replace surgery. This technique, however, still has higher complications rates than standard endoscopic mucosal resection and requires highly skilled endoscopists.

SUMMARY

The techniques, indications, and pathological assessment methods of endoscopic resection of early gastric cancer are described so that proper treatment guidelines can be established and long-term outcome data can be assessed.

Grasping forceps-assisted endoscopic mucosal resection of early gastric cancer with a novel 2-channel prelooped hood

BACKGROUND

Endoscopic mucosal resection with a cap-fitted panendoscope (EMRC) such as a soft prelooped hood is a useful, effective, and safe technique. One problem with this method is that the lesion cannot always be maintained in the center of the cap because the procedure is performed blindly after aspiration.

OBJECTIVE

We developed a 2-channel prelooped hood that facilitates EMRC while simultaneously allowing both grip of the center in the lesion and irrigation of the aspiration site and evaluated the usefulness of this end hood for early gastric cancer.

DESIGN

Retrospective study.

SETTING

Between August 2003 and October 2004, patients underwent our novel EMR.

PATIENTS

Twelve cases of early gastric cancer.

INTERVENTIONS

Two side holes were fabricated by drilling in the cap portion of a conventional soft prelooped hood, and then the irrigation tube and the accessory channel tube were glued to the exterior surface of the holes. We placed the fabricated transparent hood at the tip of the endoscope and performed grasping forceps-assisted endoscopic aspiration mucosectomy.

MAIN OUTCOME MEASUREMENTS

Accurate aspiration and the rate of en bloc resection.

RESULTS

We obtained a satisfactory field of view and accurate aspiration in the center of the tumor in all lesions. The rate of en bloc resection was 91.7% (11/12).

LIMITATIONS

Gastric intramucosal cancer.

CONCLUSION

Grasping forceps-assisted endoscopic mucosal resection with a novel 2-channel prelooped hood is safe and useful for mucosal resection of intramucosal cancers less than 20 mm and may help center the lesion in the cap before resection.

Interventional gastroenterology: esophageal and pancreatic cancers

The development and refinement of endoscopic procedures have greatly improved the diagnosis and management of esophageal and pancreatic cancers. Endoscopic ultrasound (EUS) is a highly accurate technique for TNM staging in esophageal cancer, and allows a tissue diagnosis of lymph nodes via fine-needle aspiration with low risk of complications. Endoscopic mucosal resection is a treatment option in patients with early esophageal cancer who are poor surgical candidates. Similarly, EUS fine-needle aspiration is helpful in establishing a diagnosis in cystic lesions, exocrine tumors, neuroendocrine tumors, and other lesions in the pancreas. Endoscopic retrograde cholangiopancreatography provides diagnostic and therapeutic modalities for various pancreaticobiliary problems. A number of promising EUS-guided therapies for pancreatic cancers are under investigation.

Interventional endoscopy

PURPOSE OF REVIEW

This review is an update of key issues in gastric interventional endoscopy. It focuses on the areas of patient preparation, endoscopic mucosal resection, gastroduodenal stenting, and endoscopic placement of enteric feeding tubes.

RECENT FINDINGS

Clopidogel (Plavix), a newer antiplatelet agent, can increase the risk of bleeding. Therefore, in selected cases, it should be held for 7-10 days prior to interventional procedures. In experienced hands, endoscopic mucosal resection (success rate, 76-100%; complication rate, 4-28%) and gastroduodenal stenting (success rate, 81-92%; complication rate, 1-17%) seem to be safe and effective techniques.

SUMMARY

The field of interventional endoscopy continues to advance and to conquer new frontiers. These advances create new problems that need to be addressed and studied by researchers, however. It is only through these types of reviews that our state of knowledge can be updated to help provide the latest information for clinicians in the field and to challenge researchers with future problems that need to be studied.