Endosonography probe-guided endoscopic mucosal resection of gastric neoplasms

Endoscopic submucosal dissection using a grasping-type scissors forceps for early gastric cancers and adenomas

AIM

To reduce the risk of complications related to endoscopic submucosal dissection (ESD) using knives, we developed a new grasping-type scissors forceps (GSF) that can grasp and incise the target tissue using electrosurgical current. The aim of the present study was to evaluate the efficacy and safety of ESD using GSF for the removal of early gastric cancers and adenomas.

METHODS

ESD using GSF was carried out on 35 consecutive patients with early gastric cancers or adenomas who had preoperative EUS diagnoses of mucosal tumor without lymph node involvement. Therapeutic efficacy and safety were assessed.

RESULTS

All lesions were treated easily and safely without unexpected incision. The mean size of epithelial tumors and resected specimens was 15.6mm and 32.7mm, respectively. Curative en-bloc resection rates according to tumor size and location were 96% (26/27) in tumors ≤20mm, 100% (8/8) in tumors >20mm, 100% (18/18) of tumors in the lower portion, 100% (8/8) of tumors in the middle portion, 89% (8/9) of tumors in the upper portion, and 97% (34/35) overall. The mean operating time according to tumor size and location was 93.4min in tumors ≤20mm, 140min in tumors >20mm, 77.6min for tumors in the lower portion, 113.4min for tumors in the middle portion, 148.6min for tumors in the upper portion, and 104.1min overall. No intraoperative complication occurred, and postoperative bleeding was seen in 3% (1/35).

CONCLUSIONS

ESD using GSF allows simple and safe en-bloc resection of early gastric cancer or adenoma irrespective of tumor size and location.

Treatment of gastric remnant cancer post distal gastrectomy by endoscopic submucosal dissection using an insulation-tipped diathermic knife

AIM: To evaluate the effectiveness of endoscopic submucosal dissection using an insulation-tipped diathermic knife (IT-ESD) for the treatment of patients with gastric remnant cancer.

METHODS: Thirty-two patients with early gastric cancer in the remnant stomach, who underwent distal gastrectomy due to gastric carcinoma, were treated with endoscopic mucosal resection (EMR) or ESD at Sumitomo Besshi Hospital and Shikoku Cancer Center in the 10-year period from January 1998 to December 2007, including 17 patients treated with IT-ESD. Retrospectively, patient backgrounds, the one-piece resection rate, complete resection (CR) rate, operation time, bleeding rate, and perforation rate were compared between patients treated with conventional EMR and those treated with IT-ESD.

RESULTS: The CR rate (40% in the EMR group vs 82% in the IT-ESD group) was significantly higher in the IT-ESD group than in the EMR group; however, the operation time was significantly longer for the IT-ESD group (57.6 ± 31.9 min vs 21.1 ± 12.2 min). No significant differences were found in the rate of underlying cardiopulmonary disease (IT-ESD group, 12% vs EMR group, 13%), one-piece resection rate (100% vs 73%), bleeding rate (18% vs 6.7%), and perforation rate (0% vs 0%) between the two groups.

CONCLUSION: IT-ESD appears to be an effective treatment for gastric remnant cancer post distal gastrectomy because of its high CR rate. It is useful for histological confirmation of successful treatment. The long-term outcome needs to be evaluated in the future.

Clinicopathologic factors influence accurate endosonographic assessment for early gastric cancer

BACKGROUND AND OBJECTIVE

EUS has become a valuable tool for the selection of patients who are suitable for EMR of early gastric cancer (EGC). The aim of this study was to evaluate the various clinicopathologic factors affecting the diagnostic accuracy of EUS in EGC.

DESIGN AND SETTING

A retrospective, single-center study.

PATIENTS

A total of 206 patients suspected of EGC endoscopically who underwent EUS examination and curative treatment for EGC at Severance Hospital, Seoul, Korea, from October 2001 to May 2005 were included.

INTERVENTIONS

We reviewed the medical records of 206 patients and compared preoperative EUS staging with final histopathologic staging of the resected specimen according to the clinicopathologic parameters.

MAIN OUTCOME MEASUREMENTS AND RESULTS

The diagnostic accuracy of EUS for predicting tumor invasion depth was significantly affected by the histopathologic differentiation and the size of tumor. The differentiated cell types were associated with higher diagnostic accuracy in predicting the tumor invasion. Lesions located in the mid one third of the stomach larger than 3 cm had significantly higher probability of overstaging. Poorly differentiated histologic diagnosis had a significantly higher probability of understaging. There was no significant factor associated with the endosonographic prediction of lymph node metastasis.

CONCLUSIONS

EGC with undifferentiated histopathologic features or large tumor size is more frequently associated with an incorrect diagnosis in tumor invasion depth by EUS. EGC with a size larger than 3 cm and poorly differentiated histologic diagnosis should be cautiously considered in the decision on treatment modality by pretreatment EUS staging.

Endoscopic Mucosal Resection of Lateral Spreading Tumors of the Colon Using a Novel Solution

Lateral spreading tumors (LSTs) of the colon are lesions over 10 mm in diameter that are low in height and grow superficially. They are increasingly being diagnosed in Western cohorts. The aim of this study was to investigate the safety and efficacy of dextrose 50% solution in the endoscopic mucosal resection (EMR) of LSTs. The study population consisted of 21 patients with LSTs of the colorectum. The mean size of the LSTs was 23.52+/-13.60 mm. Dextrose 50% solution was injected, via a variceal needle, into the submucosa to lift up the LST sufficiently from the proper muscle layer. Subsequently, a snare was positioned around the lesion and then closed while being pressed against the mucosa, with suction being applied to draw the lesion into the snare. Blended current was used for resection. If necessary, a piecemeal technique was used to achieve complete resection. Immediate and delayed complications were recorded. After the EMR, patients were followed up at 3, 6, and 12 months or later, using total colonoscopy. Endoscopic resection was completed in all LSTs. Of the 21 LSTs, 15 (71.4%) were resected en bloc and 6 (28.6%) piecemeal. The mean amount of injected dextrose 50% solution was 14.86+/-9.13 mL. One patient (4.78%) had immediate bleeding after EMR, which was stopped endoscopically. Histologic examination of resected LSTs showed adenoma with high-grade dysplasia 9 (42.9%), adenoma with low-grade dysplasia 10 (47.6%), and invasive carcinoma 2 (9.5%). Twenty patients were followed up for 37.9+/-24.03 months. Local recurrent disease was detected in 4 patients (20%), all within 6 months of the index EMR. These recurrent lesions were completely resected endoscopically. The contribution of submucosal injection of dextrose 50% is significant for a safe and efficient EMR of LSTs of the colorectum.

Endoscopic resection with hypertonic saline-solution-epinephrine injection plus band ligation for large pedunculated or semipedunculated gastric polyp

BACKGROUND

Endoscopic resection of pedunculated polyps with heads 1 cm or greater in diameter presents a risk of bleeding. To minimize this complication, we performed endoscopic resection with hypertonic saline-solution-epinephrine injection plus band ligation and evaluated its safety and effectiveness.

METHODS

Seventeen patients with 20 pedunculated or semipedunculated polyps with heads 1 cm or greater in diameter were treated with this technique. Conventional upper-GI endoscope, hypertonic saline-solution and epinephrine, sclerotherapy needle, and endoscopic band ligator device are needed for the procedure.

OBSERVATIONS

All lesions were easily and safely resected. During this procedure, a band ligation chamber proved to be satisfactory for accurate recognition of a postpolypectomy ulcer under good visual control. No hemorrhage, perforation, or other complication occurred as a result of the use of this technique. The histologic resection margin was affected by nonneoplastic components in 6 of 20 lesions. Follow-up endoscopy 1 week later revealed a small, shallow ulcer without residual polyp in all lesions.

CONCLUSIONS

This preliminary study suggests that endoscopic resection with hypertonic saline-solution-epinephrine injection plus band ligation is a simple and effective method for the prevention of polypectomy-associated bleeding. Prospective trials, including randomized controlled studies, are required to evaluate the suitability of this modality for wide clinical use.

Interventional endoscopy in the diagnosis and staging of upper gastrointestinal malignancy

Increased population longevity as well as an emphasis on earlier diagnosis and more effective treatment of cancer have created an environment for new technologies and techniques to flourish. Some of the endoscopic entities discussed in this article have not been fully validated in clinical practice. Innovative spectroscopic modalities hold a great deal of promise, but are years away from general applicability. In contrast, many interventional endoscopic techniques are currently available and confer heightened levels of diagnostic and staging accuracy for gastric and esophageal malignancies. Earlier diagnosis can identify patients who may be eligible for less-invasive treatment options such as EMR. Minimally invasive treatment options and maximum staging accuracy are more important for patients who are marginal surgical candidates and for accurate comparison of clinical trials studying treatment options. Our challenge for the future is to properly integrate these technologic advances with the science of good medical practice.

Efficacy, safety, and clinical outcomes of endoscopic mucosal resection: a study of 101 cases

BACKGROUND

Endoscopic mucosal resection (EMR) is an alternative to surgery for removal of superficial neoplastic lesions of the GI tract. The aim of this study was to assess the safety, efficacy, and clinical outcomes of EMR.

METHODS

Data from consecutive EMR procedures performed by using suction cap-assisted and/or saline solution-assisted snare resection techniques over a 45-month period were reviewed retrospectively. EUS was performed before EMR in the majority of cases. Immediate and delayed complications were recorded. Survival was assessed in patients with carcinoma or high-grade dysplasia on final histopathology in whom EMR achieved complete resection.

RESULTS

One hundred one lesions were removed by EMR in 92 patients. Indications were adenoma (67%), high-grade dysplasia (13%), intramucosal carcinoma (11%), and lesions of uncertain histopathology (10%). Locations were esophagus 19%, stomach 14%, duodenum 27%, rectum 12%, and colon 29%. Suction cap-assisted technique was used in 26% and saline solution-assisted polypectomy in 74% of cases. Complete resection was achieved in 89%. For complete resection, 17% required more than 1 session. Post-EMR histopathology was adenoma 47%, high-grade dysplasia 13%, carcinoma 16%, carcinoid 3%, benign 19%, and low-grade dysplasia 3%. EMR resulted in upgrading of histopathologic staging to carcinoma or high-grade dysplasia in 44%. Bleeding was the only complication (early 16, delayed 6). The median cancer-free survival in patients with adenocarcinoma who underwent complete resection by EMR was 27 months (interquartile range: 17-28 months).

CONCLUSION

EMR achieves complete resection in a majority of patients but is associated with a higher risk of bleeding compared with standard polypectomy. EMR changes pathologic stage in a significant number of patients. Survival data are encouraging, but long-term follow-up studies are needed.

Clinical outcome of endoscopic mucosal resection for superficial GI lesions and the role of high-frequency US probe sonography in an American population

BACKGROUND

Endoscopic mucosal resection, a major advance in endoscopy, provides an endoscopic option for management of focal and superficial lesions of the gastrointestinal tract. Although popular in the Orient due to the high incidence of superficial neoplasia, there are scant data on its use in the United States. Our aim was to assess the efficacy and safety of endoscopic mucosal resection in our patient population and evaluate whether high-frequency ultrasound (US) probe sonography provides useful information relative to the procedure.

METHODS

Endoscopic mucosal resection was performed in 32 of 33 patients referred for endoscopic management of superficial neoplastic or submucosal lesions. High-frequency US probe sonography was performed with a 20 MHz US probe. Endoscopic mucosal resection was performed after submucosal saline solution injection with the strip biopsy technique.

RESULTS

Thirty-two superficial lesions were resected. Of 24 epithelial lesions resected, 22 were intramucosal and 2 had early submucosal invasion (SM1); the 2 patients with the latter 2 lesions were poor candidates for surgery. Depth of penetration of 25 of 26 lesions scanned was accurately predicted by high-frequency US probe sonography. Eight lesions raised from the submucosa. Minor complications were limited to the colon. Of the 7 patients with carcinomas, 6 had no evidence of recurrence at a mean follow-up of 12 months; 1 died of a second primary cancer.

CONCLUSIONS

Endoscopic mucosal resection provided definitive therapy for 24 early-stage neoplastic lesions and provided a diagnosis in the remaining 8. In our study, the technique proved to be safe with only three minor complications noted. High-frequency US probe sonography accurately delineated the depth of penetration of all lesions scanned, therefore making it an ideal imaging modality for selecting patients who may benefit from endoscopic mucosal resection.

Imaging of esophageal tumors with a water-filled condom and a catheter US probe

BACKGROUND

High-frequency catheter ultrasound (C-EUS) probes provide high resolution images of the gastrointestinal tract. Their use in the esophagus is limited by the requirement for a water-filled lumen for good acoustical coupling. We have developed a system using a condom that provides a continuous column of water for high resolution C-EUS imaging of the esophagus.

METHODS

Nine patients underwent condom C-EUS for evaluation of esophageal mucosal and submucosal tumors. A standard latex condom was attached to a 2-channel endoscope and filled with water after esophageal intubation. A 20 MHz C-EUS probe placed within the water-filled condom was used to characterize all lesions.

RESULTS

The condom C-EUS system provided a 360 degree, high resolution image throughout the length of the esophagus without air artifact and without the risk of aspiration associated with filling the esophageal lumen with water. Complete imaging of the tumor was obtained in all cases, and no additional C-EUS procedures were required. The condom C-EUS was subjectively rated superior overall in comparison to standard C-EUS by 4 independent endosonographers.

CONCLUSIONS

Condom C-EUS is a new method of high resolution imaging of the esophagus. This method provides a contained column of water within the esophagus that improves image quality and ease of use and may reduce the risk of aspiration.

The role of gastrointestinal endosonography in diagnostic and therapeutic interventional procedures

Over the past 15 years endoscopic ultrasonography (EUS) has become an integrated part of gastrointestinal imaging. The more recent development of echoendoscopes and needles for EUS guided fine needle aspiration has stimulated the interest in interventional EUS procedures, both for diagnostic and therapeutic purposes. This paper describes the technique and experience with some of the interventional EUS procedures based on the present literature. Many of the techniques must still be considered experimental and will need substantial clinical testing in larger series before any final conclusions can be made. However, the present level of interventional EUS seems to indicate, that some of these techniques could be cost-effective alternatives in specific clinical situations, and in some cases even the only possible theraputic action. Future research in interventional EUS should be concentrated in experienced endosonography centers under careful monitoring of complications and clinical outcome.

Clinical implications of endoluminal ultrasonography using through-the-scope catheter probes

BACKGROUND

Ultrasound catheter probe-assisted endosonography is a relatively new technique. The aim of this prospective multicenter study was to determine its potential clinical impact by assessing changes in diagnostic and therapeutic management affected by catheter probes compared with ultrasound endoscopes.

METHODS

Endosonographers at three centers selected theoretic diagnostic and therapeutic plans that would be followed if neither catheter probes nor ultrasound endoscopes were available. Patients with suitable lesions underwent endosonography with catheter probes followed by an ultrasound endoscope. Diagnostic and therapeutic plans were noted after each examination.

RESULTS

Sixty-six patients, of whom 15 had a stenotic esophageal cancer, 39 had a mucosal or submucosal lesion, and 12 had a stricture of the pancreaticobiliary system or the gastrointestinal tract, were enrolled. If neither form of endosonography were available, invasive or surgical diagnostic procedures would have been performed on 23 (35%) patients and surgical therapy would have been planned in 31 (47%) patients. Catheter probe-assisted ultrasonography and endoscopic ultrasonography led to a less invasive diagnostic plan in 11 (16%) and 12 (18%) patients and a less invasive therapeutic plan in 10 (15%) and 14 (21%) patients, respectively (p > 0.1 for differences).

CONCLUSIONS

Catheter probe-assisted endosonography has a modest effect on diagnostic and therapeutic management, comparable with endoscopic ultrasonography in the same patients. The vast majority of effected changes are toward less invasive management.

Pretreatment staging of endoscopically early gastric cancer with a 15 MHz ultrasound catheter probe

BACKGROUND

The usefulness of and problems associated with an ultrasound catheter probe in the pretreatment staging of endoscopically early gastric cancer remain unexplored.

METHODS

Endoscopic ultrasonography using a 15 MHz catheter probe of 2.6 mm diameter was performed in a prospective study to determine the pretherapy staging of endoscopically early gastric cancer in 78 patients. The results of the ultrasound images were compared with the histologic findings of the specimens obtained by endoscopic mucosal resection or surgical resection.

RESULTS

The accuracy of the catheter probe for depth of invasion of endoscopically early gastric cancers was 67% (52 of 78 patients). The accuracy in determining depth of invasion in relation to endoscopic type was significantly higher for the elevated type (91%) than for the depressed type of early cancer (56%) (p < 0.01). The staging accuracy classified by histologic type was significantly higher for differentiated (86%) than for undifferentiated (18%) cancer (p < 0.01). Staging accuracy decreased as tumor size increased. The accuracy, sensitivity, and specificity for nodal staging were 80%, 17%, and 90%, respectively.

CONCLUSIONS

A 15 MHz ultrasound catheter probe is most useful for determining depth of invasion when the tumor is histologically differentiated and endoscopically of the small elevated type early gastric cancer, but it is unreliable in the diagnosis of metastatic lymph nodes.

Pre-operative TN staging of gastric cancer using a 15 MHz ultrasound miniprobe

The aim of the study was to evaluate the usefulness of and problems associated with a new endoscopically guided ultrasound miniprobe, used for pre-operative staging of gastric cancers. 59 cases of gastric cancer were prospectively examined with a 15 MHz ultrasound miniprobe. The results of the ultrasound imaging were compared with the histological findings of the resected specimens. The accuracy of the miniprobe for depth of invasion (T category) was 61% for all tumours, and 72% and 40%, respectively, for T1 and T2 to T4 lesions. If indeterminate cases due to ultrasound attenuation were excluded, the accuracy was improved to 82% for T1 and 57% for T2 to T4 tumours, respectively. The accuracy of the miniprobe for nodal staging (N category) was 69% overall, and 86%, 25% and 14% for stages N0, N1 and N2, respectively. In tumours classified on the basis of endoscopic types, the miniprobe staged early type gastric cancers (T category = 73%, N category = 80%) significantly (p < 0.01) more accurately than advanced ones (T category = 21%, N category = 36%). This study suggests that the miniprobe is indicated for pre-operative TN staging when endoscopy reveals an early gastric cancer.