Endosonography-guided endoscopic resection of duodenal carcinoid tumor

Long-term outcome of endoscopic and surgical resection for foregut neuroendocrine tumors

OBJECTIVE

Endoscopic resection (ER) of foregut neuroendocrine tumors (NETs) is increasingly performed instead of surgery. This study aimed to compare the long-term therapeutic outcomes of ER and surgical resection (SR) for foregut NETs.

METHODS

From 2002 to 2012, a total of 49 patients with histologically confirmed foregut NETs were treated by ER (n = 33) and SR (n = 16). The clinicopathological characteristics and therapeutic outcomes were evaluated.

RESULTS

Of the 33 patients who underwent ER [endoscopic mucosal resection (n = 26), endoscopic mucosal dissection (n = 7)], 32 were diagnosed as NET-G1 and NET-G2, and the other as neuroendocrine carcinoma (NEC). Of the 16 patients who underwent SR, 10 were diagnosed as NET-G1, 2 as NET-G2 and 4 as NEC. The median tumor size was significantly smaller in the ER group compared with the SR group (7 mm vs 19 mm, P = 0.001). In almost all patients treated with ER (32/33), NET invasion was limited to the mucosa and submucosa. Non-curative resections were observed in 24.2% of the patients in the ER group (8/33) and 25.0% in the SR group (4/16). No recurrence occurred in NET cases with positive resection margins by ER. However, all cases of non-curative resection with lymphatic invasion (one in the ER group and four in the SR group) developed liver metastasis during the follow-up despite complete resection, and all these five patients has histologically confirmed NECs.

CONCLUSION

NET patients treated by ER may have a good prognosis if the tumor size is small and histologically low grade without lymphatic invasion.

Endoscopic treatment for early foregut neuroendocrine tumors

Foregut neuroendocrine tumors (NETs) include those arising in the esophagus, stomach, pancreas, and duodenum and seem to have a broad range of clinical behavior from benign to metastatic. Several factors including the advent of screening endoscopy may be related to increased incidence of gastrointestinal NETs; thus, many foregut NETs are diagnosed at an early stage. Early foregut NETs, such as those of the stomach and duodenum, can be managed with endoscopic treatment because of a low frequency of lymph node and distant metastases. However, controversy continues concerning the optimal management of early foregut NETs due to a lack of controlled prospective studies. Several issues such as indications, technical issues, and outcomes of endoscopic treatment for early foregut NETs are reviewed based on some published studies.

Endoscopic mucosal resection with circumferential mucosal incision of duodenal carcinoid tumors

Duodenal carcinoids are a rare form of neuroendocrine tumors, and tend to invade the submucosa during the early stage. Endoscopic treatment is generally recommended for duodenal carcinoids less than 10 mm in diameter. Although a few reports have described the use of endoscopic resection of duodenal carcinoids, there are no published studies on endoscopic mucosal resection with circumferential mucosal incision (EMR-CMI). We performed EMR-CMI for 5 cases of duodenal carcinoids in the duodenal bulb. The mean tumor diameter was 4.6 ± 1.8 mm. Although all of the tumors were located in the submucosa, R0 resection was performed without complication in each case. EMR-CMI may thus be a safe and effective treatment for duodenal carcinoids less than 10 mm in diameter.

Endoscopic approach to the patient with benign or malignant ampullary lesions

Adenoma and adenocarcinoma are the most common ampullary lesions. Advances in diagnostic modalities including endoscopic ultrasonography and intraductal ultrasonography have provided useful information that aids in diagnosing and managing ampullary lesions. Endoscopic papillectomy can be a curative therapy for localized ampullary adenoma and have a role in the diagnosis of indeterminate ampullary lesions that may contain a hidden malignancy. However, the consensus on how and when to use endoscopic papillectomy has not been fully established. This article reviews the approach to the patient with benign or malignant ampullary lesion.

Endoscopic submucosal dissection for foregut neuroendocrine tumors: An initial study

AIM: To evaluate the feasibility and efficacy of endoscopic submucosal dissection (ESD) for foregut neuroendocrine tumors (NETs).

METHODS: From April 2008 to December 2010, patients with confirmed histological diagnosis of foregut NETs were included. None had regional lymph node enlargement or distant metastases to the liver or lung on preoperative computerized tomography scanning or endoscopic ultrasonography (EUS). ESD was attempted under general anesthesia. After making several marking dots around the lesion, a mixture solution was injected into the submucosa. The mucosa was incised outside the marking dots. Dissection of the submucosal layer beneath the tumor was performed under direct vision to achieve complete en bloc resection of the specimen. Tumor features, clinicopathological characteristics, complete resection rate, and complications were evaluated. Foregut NETs were graded as G1, G2, or G3 on the basis of proliferative activity by mitotic count or Ki-67 index. All patients underwent regular follow-up to evaluate for any local recurrence or distant metastasis.

RESULTS: Those treated by ESD included 24 patients with 29 foregut NETs. The locations of the 29 lesions are as follows: esophagus (n = 1), cardia (n = 1), stomach (n = 23), and duodenal bulb (n = 4). All lesions were found incidentally during routine upper gastrointestinal endoscopy for other indications, and none had symptoms of carcinoid syndrome. Preoperative EUS showed that all tumors were confined to the submucosa. Among the 24 gastric lesions, 16 lesions in 11 patients were type I gastric NETs arising in chronic atrophic gastritis with hypergastrinemia, while the other 8 solitary lesions were type III because of absence of atrophic gastritis in these cases. All of the tumors were removed in an en bloc fashion. The average maximum diameter of the lesions was 9.4 mm (range: 2-30 mm), and the procedure time was 20.3 min (range: 10-45 min). According to the World Health Organization 2010 classification, histological evaluation determined that 26 lesions were NET-G1, 2 gastric lesions were NET-G2, and 1 esophageal lesion was neuroendocrine carcinoma (NEC). Complete resection was achieved in 28 lesions (28/29, 96.6%), and all of them were confined to the submucosa in histopathologic assessment with no lymphovascular invasion. The remaining patient with NEC underwent additional surgery because the resected specimens revealed angiolymphatic and muscularis invasion, as well as incomplete resection. Delayed bleeding occurred in 1 case 3 d after ESD, which was managed by endoscopic treatment. There were no procedure-related perforations. During a mean follow-up period of 24.4 mo (range: 12-48 mo), local recurrence occurred in only 1 patient 7 mo after initial ESD. This patient successfully underwent repeat ESD. Metastasis to lymph nodes or distal organs was not observed in any patient. No patients died during the study period.

CONCLUSION: ESD appears to be a safe, feasible, and effective procedure for providing accurate histopathological evaluations and curative treatment for eligible foregut NETs.

Endoscopic resection of duodenal bulb neuroendocrine tumor larger than 10 mm in diameter

Background

Endoscopic treatment for duodenal bulb neuroendocrine tumor larger than 10 mm is still controversial. This report presents four cases successfully treated with endosonography (EUS)-assisted endoscopic mucosal resection (EMR) procedure for duodenal bulb neuroendocrine tumor larger than 10 mm in diameter.

Methods

The case series of four patients diagnosed with neuroendocrine tumor from 2003 to 2008 were reviewed. EUS demonstrated well-defined hypoechoic tumors confined to the submucosal hyperechoic layer and the underlying hypoechoic muscularis propria was intact in all four patients. EMR were planned and performed for the duodenal bulb neuroendocrine tumors larger than 10 mm.

Results

En bloc resections with tumor free lateral and basal margins were accomplished using an endoscopic diathermic snare with forward-viewing instruments without any complications. Neither residual duodenal neuroendocrine tumors nor metastatic lesions were detected during the observation period ranging 19 to 78 months

Conclusion

Duodenal bulb neuroendocrine, larger than 10 mm in diameter, can be treated by endoscopic procedure, after confirming that the tumor confined to the submucosal layer in EUS examination, and no lymph node involvement by abdominal CT and US.

Resolved and unresolved controversies in the surgical management of patients with Zollinger-Ellison syndrome

OBJECTIVE

Highlight unresolved controversies in the management of Zollinger-Ellison syndrome (ZES).

SUMMARY BACKGROUND DATA

Recent studies have resolved some of the previous controversies including the surgical cure rate in patients with and without Multiple Endocrine Neoplasia-type1 (MEN1), the biological behavior of duodenal and pancreatic gastrinomas, role of imaging studies to localize tumor, and gastrectomy to manage acid output.

METHODS

Review of the literature based on computer searches in Index Medicus, Pubmed and Ovid.

RESULTS

Current controversies as identified in the literature include the role of endoscopic ultrasound (EUS), surgery in ZES patients with MEN1, pancreaticoduodenectomy (Whipple procedure), lymph node primary gastrinoma, parietal cell vagotomy, reoperation and surgery for metastatic tumor, and the use of minimally invasive surgical techniques to localize and remove gastrinoma.

CONCLUSIONS

It is hoped that future studies will focus on these issues to improve the surgical management of ZES patients.

Experimental endoscopic repair of gastric perforations with an omental patch and clips

BACKGROUND

The omental patch is a standard surgical treatment of gastroduodenal ulcer perforation. This is a report of an experimental method for endoscopic repair of anterior gastric perforations with an omental patch developed by using a porcine model.

METHODS

A standardized gastric perforation was created in 10 pigs. The omentum was pulled into the gastric lumen and fixed endoscopically to the muscularis propria layer of the stomach with metallic clips.

RESULTS

The postoperative course was normal in 9 animals. An ulcer was evident at the site of repair at follow-up endoscopy. At autopsy, the omentum was adherent to the external side of gastric wall. One animal died with peritonitis, presumably because the muscularis propria layer could not be seen during the procedure, and the clips attached the omentum only to the mucosa.

CONCLUSIONS

Endoscopic repair with an omental patch appears to be an effective procedure for closure of gastric perforations.

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.

[Laparoscopic excision of a duodenal neuroendocrine tumor]

A 75-year-old woman with melena was found to have a carcinoid tumor in the posterior wall of the duodenal bulb. The biology was normal. The tumor measured 10 mm in size, and endoscopic ultrasonography showed only submucosal involvement. There was no liver metastasis and no regional lymph nodes. Tumoral resection was performed laparoscopically with success. Postoperative course was uneventful. Laparoscopic resection could be an appropriate minimally invasive treatment for selected small size duodenal tumors.

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.

Diagnosis of submucosal tumor of the upper GI tract by endoscopic resection

BACKGROUND

Submucosal tumors are frequent findings during endoscopy, although definitive diagnosis based on histologic confirmation presents some difficulties. The aim of this study was to evaluate the efficacy and safety of endoscopic resection based on endoscopic ultrasonography (EUS) findings to reach a definitive diagnosis of submucosal tumor.

METHODS

Fifty-four submucosal tumors of the upper gastrointestinal (GI) tract were included in this study. EUS was performed to determine the layer of origin and location of the lesion and to rule out malignancy. En bloc resection was attempted for lesions originating in the muscularis mucosa or submucosa. For tumors originating in the muscularis propria, we performed partial resection limited to the covering mucosa to expose the lesion and obtained a sample with standard biopsy forceps.

RESULTS

Sufficient samples were obtained in all 54 cases. There was no perforation. Bleeding occurred in only 5 cases (9%) and was easily managed with endoscopic hemostatic methods. EUS and pathologic findings coincided in 74.1% of cases (40 of 54). Benign lesions (leiomyoma, aberrant pancreas, and others) were predominant (52 of 54), although 2 small lesions were confirmed at pathologic study to be malignant (leiomyosarcoma and leiomyoblastoma).

CONCLUSIONS

Endoscopic resection based on EUS findings proved to be an effective and safe method to confirm the histologic diagnosis of submucosal tumor of the upper GI tract. Endoscopic resection should be considered a valuable choice for definitive management of benign submucosal tumors originating in the superficial layers.