Natural orifice transluminal endoscopic surgery (NOTES)

A current review and update of an exceedingly novel and appealing topic, namely natural orifice transluminal endoscopic surgery (NOTES), is discussed, as well as the authors viewpoint thereon. Most reviewed studies were performed in laboratory animals, but reports on transvaginal cholecystectomy and the emergence of editorials and review articles on this topic pose a number of as yet unanswered questions on this type of surgery, which represents a potential advance towards "endoscopic surgery with no scars, no infection, minimal anesthesia requirements, and immediate recovery".

Neuroendocrine tumors - fascination and infrequency

In this article, I review and update of gastro-entero-pancreatic neuroendocrine tumors, which so much fascination have risen among healthcare providers on grounds of their infrequency, hormonal syndromes, and high survival rate, is performed based on references from the past fifteen years.

[Tridimensional (3D) endoscopic ultrasonography]

A review and update on 3D endoscopic ultrasonography is included regarding all of this technique s aspects, technical details, and current indications. Images from our own clinical experience are presented.

Preoperative detection of gastrointestinal neuroendocrine tumors using endoscopic ultrasonography

OBJECTIVE

Almost 30% of gastroenteropancreatic neuroendocrine tumors (GEPET) escape preoperative identification using standard imaging techniques. The goal of this retrospective study is to present our cumulative experience in the assessment of GEPET by preoperative endoscopic ultrasonography (EUS), and to compare it with a literature review.

PATIENTS AND METHODS

Thirty-seven patients with suspected specific hormonal syndromes were sequentially examined with US, CT, MRI, angiography, OctreoScan, and radial and sectorial EUS. Sixteen were males (43%) and 21 were females (57%), with a mean age of 61 years (interval: 40-84 a). Of all 37 patients, 27 had 19 endocrine tumors in the pancreas and 14 tumors in their gastrointestinal tract. No tumors were demonstrated in 10 patients, hence they were used as a control group. Of all 37 patients, 24 were operated on or had histological samples collected, with the presence of 26 GEPET (10 carcinoids) being confirmed in 22 patients.

RESULTS

EUS sensitivity and diagnostic accuracy were 81% and 78%. Specificity was 80%. All these values were similar to the mean values obtained from the literature review. Three pancreatic rumors smaller than or equal to 1 cm (insulinomas) were detected, which had escaped diagnosis with previous US, CT, and MRI studies. An echoendoscopic examination of the pancreas could not be completed in two cases (5%), a pancreas carcinoid and an already gastrectomized double pancreatic gastrinoma.

CONCLUSION

EUS is a good preoperative technique for GEPET detection, and may likely be superior to other imaging techniques in the assessment of small tumors. The usefulness of EUS as a primary exploration after US or HCT has been posited for tumor diagnosis and localization before surgery.

EUS-guided mucosectomy for gastrointestinal cancer

INTRODUCTION

the only way of improving prognosis and survival in gastrointestinal cancer is early diagnosis, with intramucosal localization as confirmed by endoscopic ultrasonography (EUS) or 20-MHz miniprobes (MPs) (T1) being most appropriate. Endoscopic mucosal resection (EMR) has proven effective in the treatment of this sort of lesions.

PATIENTS AND METHOD

in a group (18 cases) with 15 cases of superficial gastrointestinal cancer and 3 cases of severe gastric dysplasia, 9 cases (3 esophageal, 4 gastric, 2 rectal) underwent a classic EMR following EUS or a 7.5- and 20-MHz miniprobe exploration.

RESULTS

ultrasonographic studies showed a T1 in all but one esophageal case (Tis), and in both gastric dysplasias, with no changed layer structure being demonstrated in the latter (T0). No complications arose with classic EMR, and all 9 patients are alive and free from local or metastatic recurrence, except for one esophageal case, which recurred distally to the esophageal lesion (metachronous).

CONCLUSIONS

echoendoscopically-assisted EMR is a safe, effective technique in the endoscopic management of superficial gastrointestinal (esophageal, gastric, colorectal) cancer. Recurrence most likely depends upon cancer multiplicity.

Tridimensional (3D) ultrasonography

A review and update on tridimensional ultrasonography covering all its aspects, ultrasonography and 3D endoscopic ultrasonography, its technical details and current indications, such as volume calculation, vascular architecture assessment, and role in interventionist ultrasounds. Images included are from the author's own experience.

Endoscopic ultrasound-assisted endoscopic resection of carcinoid tumors of the gastrointestinal tract

INTRODUCTION

Usually found in the gastrointestinal tract, carcinoids are the most frequent neuroendocrine tumors. Most of these lesions are located in areas that are difficult to access using conventional endoscopy (small intestine and appendix); carcinoid tumors found in the gastroduodenal tract and in the large intestine can be studied endoscopically; in these cases, if localized disease is confirmed, local treatment by endoscopic resection may be the treatment of choice. Since endoscopic ultrasonography has been shown to be the technique of choice for the study of tumors exhibiting submucosal growth, the selection of patients who are candidates for a safe and effective local resection should be based on this technique.

PATIENTS AND METHOD

We selected patients with gastrointestinal carcinoid tumors who were endoscopically treated between 1997 and 2002. Those patients with tumors measuring less than 10 mm, which had not penetrated the muscularis propria, and those with localized disease were considered candidates for endoscopic resection. The endpoints of this study were to assess the effectiveness (complete resection) and safety (complications) of the technique. Follow-up consisted of eschar biopsies performed one month and twelve months after the resection.

RESULTS

During the aforementioned period, we resected endoscopically 24 tumors in 21 patients (mean age: 51.7 years; 71.5% males). Most lesions were incidental discoveries made during examinations indicated for other reasons. Resection was indicated in most cases as a result of the suspected presence of a carcinoid tumor after endoscopic ultrasonography. Endoscopic ultrasonography also enabled us to clearly identify the layer where the lesion had originated, as well as the size of the lesion. The carcinoid tumor was removed in 13 cases (54.2%) by using the conventional snare polypectomy technique, in 9 cases (37.5%) assisted by a submucosal injection of saline solution and/or adrenaline, and in 2 cases (8.3%) after ligating the lesion with elastic bands. In all cases the resection was complete, with no recurrence during the follow-up period, and no major complications, except for a single case in which a post-polypectomy hemorrhage occurred that was endoscopically solved.

CONCLUSIONS

In properly selected patients, the endoscopic resection of carcinoid tumors is a safe and effective technique that permits a complete resection in all cases with few complications. Endoscopic ultrasonography is the technique of choice for selecting the patients who are candidates for endoscopic resection.

Endoscopic resection of gastrointestinal submucosal tumors assisted by endoscopic ultrasonography

BACKGROUND

The resection and histologic examination of the lesions is generally considered the treatment of choice in order to achieve diagnosis in gastrointestinal submucosal tumors. Moreover, the degree of malignancy of the tumor depends on certain features that can only be studied on the entire resected piece.

METHODS

We revised the cases of patients who underwent endoscopic resection of gastrointestinal submucosal tumors in the period from 1997 through 2002.

RESULTS

Fifty submucosal lesions were resected in 45 patients (64.4% men). Patient mean age was 55.31 years. Of the lesions, 52% were gastric tumors and 88% were located in the second layer. Mean size was 12.34 mm, and 54% were smaller than 10 mm. Resection with submucosal injection of saline solution and diluted adrenaline was performed on 46% of the lesions, and standard resection using polypectomy snare on 48%. Ligation was used in three cases. Resection was successful in 98% and major complications were observed in 4% (two cases of bleeding, endoscopically resolved).

CONCLUSIONS

The endoscopic resection of submucosal tumors is a safe and efficient technique: It has few associated complications and allows diagnosis in all the cases and cure of the lesion in the great majority of cases.

Transendoscopic ultrasound mini-probes, are they necessary?

The goal of this paper was to define the current state of mini-probes or miniaturized endoscopic ultrasound probes, their technical specifications, current clinical applications, safety and minimal risks, complications and limitations.

Miniprobe ultrasonography and gastrointestinal tract stenosis

OBJECTIVE

Malignant and nonmalignant stenosis of the gastrointestinal tract are a significant diagnostic and therapeutic challenge. Malignant stenosis is difficult to stage because the endosonographic catheter cannot be passed through the stricture. The objective of this study was to stage tumoral stenosis using a miniprobe.

METHODS

We evaluated 30 patients (20 men, 10 women, average age 65 years). There were 9 nonmalignant cases and 21 malignant cases of stenosis of the gastrointestinal tract. Of the malignant cases, two were caused by extradigestive neoformations that infiltrated the wall of the digestive tract. Twelve of the remaining 19 cases were treated by surgery (63%). Echoendoscopy was done with a miniprobe through the working channel of the videoendoscope. The TNM classification was used to diagnose extension. The pathology study was used to confirm the final diagnosis after surgery for malignant lesions. Nonmalignant stenosis was confirmed in clinical follow-up.

RESULTS

Sensitivity of the miniprobe in determining stage T and stage N were 83% and 64% respectively.

CONCLUSIONS

Miniprobes provide valuable additional information in the study of stenosis of the digestive tract. Sensitivity is good in classifying tumoral T stage, and acceptable for classifying N stage, and may be improved by using low-frequency miniprobes.

[The diagnosis and preoperative location of digestive endocrine tumors by endoscopic ultrasonography]

Around 30% of the gastroenteropancreatic endocrine tumors (GPET) cannot be preoperatively identified by the common diagnostic imaging techniques. The aim of this retrospective study was to present our experience in the diagnosis and localization of GPET by endoscopic ultrasonography (EUS) performed prior to surgery and compare this with a review of the literature.

PATIENTS AND METHODS

Twenty patients suspected of having specific hormonal syndromes were correlatively explored with US, CT, MR, angiography, octreoscan and radial EUS with Olympus GFUM3/EUM3 and GF-UM20/EUM 20 and 30. Eleven cases were males (55%) and 9 (45%) females with a mean age of 60 years (range: 40-80 years). Of the 20 patients, 14 had endocrine 16 tumors in the pancreas and 6 tumors in the gastrointestinal tract. In 6 patients no tumors were found and were therefore used as a control group. Of the 20 patients, 14 underwent surgery confirming the existence of GPET in 12 cases.

RESULTS

The diagnostic sensitivity and precision of the EUS were of 75 and 78%, respectively, with these percentages being higher to those obtained with other imaging techniques. The specificity was 83%. All these values were slightly lower than the mean obtained on review of the literature. Two pancreatic tumors of less than or equal to 1 cm were detected which had not been previously diagnosed with US, CT and MR. In two cases the exact situation was not determined. Echo-endoscopic exploration of the pancrease could not be completely performed in two cases (10%), one pancreatic carcinoma and one double pancreatic gastrinoma which was gastrectomized. Endoscopic ultrasonography is a good preoperative technique for detecting GPET and in the evaluation of small sized tumors it may surpass other imaging techniques. The usefulness of EUS as a second exploration following US has been suggested for the diagnosis and localization prior to surgery.

[The value of endoscopic ultrasonography in the study of submucosal tumors of the digestive tract]

Twenty-one consecutive patients with 24 possible submucosal lesions of the digestive tract were studied. Endoscopic ultrasonography (EUS) differentiated between 17 true positive submucosal tumors and 3 true negative extrinsic compressions. False positives were interpreted in 3 cases and in one patient no lesion was echoendoscopically observed (false negative). The sensitivity was 94%, the specificity 50% and the positive and negative predictive values were 82% and 75%, respectively. In conclusion, EUS may be the method of choice for the study of submucosal tumors since it allows visualization of the five layers of the wall of the digestive tract in which a tumor may originate, determination of its sonographic features, depth and exact size, in addition to the invasion of neighboring organs. Moreover, EUS may aid in collecting material for cytology and microscopy by fine needle aspiration puncture (FNAP) by EUS.

[Comparative study of 3 drugs (aceglutamide aluminum, zinc acexamate, and magaldrate) in the long-term maintenance treatment (1 year) of peptic ulcer]

In a multicentre study, 146 peptic ulcer patients who had recently healed with H2 antagonists (38 gastric, 108 duodenal ulcers) received randomly for a year one of the following mucosal protecting antiulcer drugs: aceglutamide aluminium salt (AAL), zinc acexamate (ZAC) and magaldrate (MAG). Forty six patients received AAL (700 mg bid), 50 patients received ZAC (300 mg at single nocturnal dose) and 50 patients received MAG (800 mg bid). An endoscopic examination was performed at the beginning of the study and 12 months later. Clinical examinations where performed on months 3, 6 and 9, advancing the endoscopical control in case of ulcer symptoms. ZAC showed to be superior to MAG (p less than 0.05, chi-square test) in preventing relapses, with a favourable tendence in front of AAL, but without reaching statistical significance. Its important to mention the high number of withdrawals and the good tolerance of the treatments.

[Pharmacological treatment of gastroenteropancreatic apudomas with an analog of somatostatin, SMS 201-995 (octreotide)]

Ten patients with gastro-pancreatic apudomas were prospectively treated with SMS 201-995 at the dose of 25-50 mg/12 h. subcutaneously before breakfast and dinner during two months. The biological and clinical effects were evaluated, as well its possible antitumoral action. When clinical or biological benefit was ascertained, the treatment was continued uninterruptedly. SMS 201-995 was well tolerated. It allows ambulatory treatment. It reduced hormonal levels in 62% of cases and controlled symptoms in 50%. No antitumoral effects were observed in the majority of patients.

[The pharmacological treatment of digestive endocrine tumors with the somatostatin analog SMS 201-995]

Eight patients suffering gastroenteropancreatic apudomas were prospectively treated with subcutaneous SMS 201-995 at a dose of 25-50 mg/12 hours, before breakfast and dinner during two months. Biological and clinical effects were evaluated as well as the possible antitumor effect. In those cases that obtained a clinical and/or biological benefit, treatment was continued uninterruptedly. The results showed that SMS 201-995 is a well tolerated drug which permits ambulatory treatment of patients with GI endocrine tumors being the main objective the reduction of hormone levels and symptom control, not finding in most cases an antitumor effect.