American Gastroenterological Association Institute technical review on the management of gastric subepithelial masses

Successful gastric submucosal tumor resection using laparoscopic and endoscopic cooperative surgery

BACKGROUND

Laparoscopic wedge resections are increasingly utilized to treat gastric submucosal tumors (SMTs). However, laparoscopic wedge resection is not applicable for tumors located near the gastric inlet or outlet and requires resection of relatively large sections of healthy stomach, particularly if laparoscopic linear staplers are used.

METHODS

Twenty consecutive patients underwent laparoscopic and endoscopic cooperative surgery (LECS) for resection of gastric SMTs. The procedure was performed under general anesthesia. The mucosal and submucosal layers around the tumor were circumferentially dissected using endoscopic submucosal dissection via intraluminal endoscopy. Subsequently, the seromuscular layer involving three-fourths of the line of the incision around the tumor was laparoscopically dissected. The submucosal tumor was then exteriorized to the abdominal cavity and dissected with an endoscopic linear stapling device.

RESULTS

In all cases, the LECS procedure was successful in dissecting the gastric SMT. The tumor was located in the upper third of the stomach in eight cases, in the middle third in eight cases, and in the lower third in four cases. The mean operating time was 157.0 ± 68.4 minutes, and the mean intraoperative blood loss was 3.5 ± 6.4 ml. The postoperative course was uneventful in all cases.

CONCLUSIONS

We demonstrated the feasibility and satisfactory surgical outcomes after LECS for gastric SMT. With LECS, relatively small sections of healthy gastric wall are resected without postoperative morbidity or mortality. Thus, LECS is safe, easy, and beneficial for laparoscopic resection of SMTs, although care should be taken to avoid gastric juice contamination.

Small intestine gastrointestinal stromal tumors

PURPOSE OF REVIEW

To review the contemporary management of gastrointestinal stromal tumor (GIST), including endoscopy, surgery, and systemic therapy, highlighting the aspects unique to small intestinal tumors.

RECENT FINDINGS

Tumor size, mitotic count, and site of origin are the three key prognostic factors, with mitotic count being the single strongest predictor of recurrence. Tumors arising in the small bowel have worse prognosis than those of comparable size and mitotic count arising in other organs. Endoscopy and endoscopic ultrasound-guided, fine-needle aspiration are key components in the diagnosis of GIST. The role of endoscopy in surveillance and resection remain investigational. Surgery, either open or laparoscopic, remains the only curative option, but recurrence rates are high. Adjuvant therapy with imatinib mesylate improves recurrence-free survival rates and may improve overall survival (OS) with longer duration of treatment. Neoadjuvant imatinib may play an important role in the management of patients with locally advanced disease. For patients with advanced disease, first-line imatinib and second-line sunitinib malate have improved progression-free and OS rates. Systemic treatment should be continued life-long or until treatment failure.

SUMMARY

Advances in the last decade have dramatically changed the management and prognosis of patients with primary and advanced GIST.

Endoscopic management of gastrointestinal stromal tumors

Subepithelial lesions are increasingly being identified with improved endoscopic imaging technologies. Many of these lesions are now recognized as gastrointestinal stromal tumors (GISTs). Recent advances in immunohistochemistry have allowed for reliable differentiation of GISTs from other subepithelial tumors, thereby significantly improving our understanding of these lesions. The wealth of recent information and continual evolution in our understanding of GISTs has exposed some knowledge gaps pertaining to the optimal management of these lesions. In this article, we review the endoscopic management of GISTs as it relates to the identification, diagnosis and management of these lesions based on the best available literature and our own clinical experience to date.

Endoscopic submucosal dissection for treatment of gastric subepithelial tumors (with video)

BACKGROUND

Endoscopic submucosal dissection (ESD) is a well-accepted method for removing superficial mucosal tumors; however, there is limited data on the use of this method for removing subepithelial tumors.

OBJECTIVE

To investigate the efficacy, safety, and outcome of ESD for gastric subepithelial tumors and determine factors related to treatment success.

DESIGN

Retrospective analysis of a prospectively maintained database.

SETTING

Single tertiary academic center.

PATIENTS AND INTERVENTIONS

From April 2007 to November 2010, 37 patients with gastric subepithelial tumors were treated with ESD.

MAIN OUTCOME MEASUREMENTS

Macroscopically and microscopically complete en block resection rate (R0), complication rate, and endosonographic features predictive of R0 resection.

RESULTS

The median tumor diameter was 25.0 mm, (range 10-60 mm, IQR 17-37). The overall rate of R0 resections was 81.1% (30/37, 95%CI: 61.8-90.2%), including 100% (15/15, 95%CI: 78.2-100.0%) of tumors from the submucosa and 68.2% (15/22, 95%CI: 45.1-86.1%) of tumors from the muscularis propria. Seventeen patients had a final diagnosis of gastrointestinal stromal tumor. The severe complication (perforation) rate was 5.4% (2/37, 95%CI: 0.0-9.5%). One patient required surgery; the other was treated conservatively. No recurrence was observed in patients with R0 resections at a median follow up of 21.0 months (IQR 11-35). Successful R0 resections were predicted by the observation of no, or only narrow, tumor connections with the underlying muscle layer during EUS (OR=35.0, 95%CI: 3.7-334.4, p=0.001).

LIMITATIONS

Single-center, retrospective analysis, short follow-up.

CONCLUSIONS

ESD is an effective and relatively safe method for removing gastric subepithelial tumors. Endoscopic ultrasonography findings can predict complete tumor resections.

Pediatric gastrointestinal stromal tumor

Pediatric gastrointestinal stromal tumor (GIST) is a rare entity that can be quite different from its adult counterpart. This report provides a comprehensive review on the diagnosis and management of this tumor in children and adolescents, including its oncogenesis and associated syndromes. Surgery remains a mainstay of treatment, but there are no standard guidelines available at this time regarding the best practice for multimodality therapy as our understanding of the biology of GIST is still in evolution. Therefore, pediatric patients with GIST should be ideally treated in the context of clinical trials at specialized, multidisciplinary centers throughout the course of their disease, especially because these patients may live for years after diagnosis.

Predictors of recurrence after resection of small gastric gastrointestinal stromal tumors of 5 cm or less

GOALS

To evaluate the recurrence predicting factors of small gastric gastrointestinal stromal tumors (GISTs) through the long-term follow-up after surgical/endoscopic resection.

BACKGROUND

Although small gastric GISTs are known to have a low risk of recurrence after complete resection, the prognostic factors are not well known.

STUDY

The study retrospectively analyzed the records of 136 patients with primary gastric GISTs of 5 cm or less without metastasis who underwent surgical/endoscopic resection between March 1997 and December 2008 at the Asan Medical Center, and who were followed-up for at least 3 months after resection. Specimens were assessed for tumor size, mitotic index, and microscopic resection margin. Specimen sections were immunohistochemically stained to determine the levels of expression of the cell cycle proteins p53, p16(INK4), pRb, cyclin D1, and Ki-67. DNA was extracted from high-risk tumors to analyze for KIT mutations.

RESULTS

Among 136 patients, 5 (3.7%) patients with tumors with a high mitotic index showed recurrence at a median 23 months post resection. None of 14 patients with microscopic positive resection margins showed recurrence during a median follow-up time of 32 months. A high mitotic index was a predictor of recurrence (P<0.001), but that tumor size, method of resection, or margin status were not. In addition, abnormal p53 expression was found to be associated with recurrence (P=0.004). All assessable high-risk tumors had a KIT exon 11 mutation.

CONCLUSIONS

Predictors of recurrence of gastric GISTs of 5 cm or less were a high mitotic index and abnormal p53 expression. A positive microscopic resection margin was not associated with recurrence.

Clinical impact of EUS-guided Trucut biopsy results on decision making for patients with gastric subepithelial tumors ≥ 2 cm in diameter

BACKGROUND

Preoperative pathologic diagnosis of a gastric subepithelial tumor (SET) may improve clinical decision making. However, the clinical impact of EUS-guided Trucut biopsy (EUS-TCB) data on decision making in patients with a gastric SET has not been assessed.

OBJECTIVE

To evaluate the impact of EUS-TCB information on the clinical management of patients with a gastric SET.

DESIGN

Retrospective review of prospectively collected data.

SETTING

Tertiary referral center.

PATIENTS

Sixty-five patients with gastric SETs 2 cm or larger in diameter.

INTERVENTION

EUS-TCB.

MAIN OUTCOME MEASUREMENTS

The number of patients for whom treatment plans were changed because of EUS-TCB results.

RESULTS

Nine SETs were not punctured by the TCB needle because of technical problems, and we were unable to obtain adequate subepithelial tissue from 19 SETs. Treatment plans were changed for 18 of 65 patients (27.7%). The changes were avoiding unnecessary resection (7 benign SETs ≥ 3 cm in diameter), scheduling for definitive treatment (6 GI stromal tumors and 1 carcinoid tumor), and modifying the surgical field (3 large GI stromal tumors and 1 carcinoma). When we assessed treatment plans relative to tumor location, we found that avoiding unnecessary resection was associated with the presence of cardiac SETs.

LIMITATIONS

Retrospective study with a small number of patients.

CONCLUSIONS

EUS-TCB changed or influenced management decisions in 18 of 65 patients (27.7%) with gastric SETs. Patients could receive proper and tailored surgery, medical treatment, or surveillance according to size and location of SETs with EUS-TCB.

EUS-guided single-incision needle-knife biopsy: description and results of a new method for tissue sampling of subepithelial GI tumors (with video)

BACKGROUND

The diagnostic efficacy of current tissue sampling techniques for upper GI subepithelial tumors (SETs) appears to be limited. Better tissue acquisition techniques are needed to improve the diagnostic yield in this setting.

OBJECTIVE

Our purpose was to determine the safety and diagnostic yield of EUS-guided needle-knife incision and forceps biopsy (SINK biopsy) of upper GI SETs.

DESIGN

Retrospective database review.

SETTING

Academic tertiary-care referral center.

PATIENTS

This study involved 14 consecutive patients referred for EUS evaluation of upper GI SETs with previous unsuccessful attempts at tissue diagnosis by conventional forceps biopsy.

INTERVENTION

EUS-guided needle-knife incision and forceps biopsy.

MAIN OUTCOME MEASUREMENTS

The safety and diagnostic yield of this method, compared with EUS-guided fine-needle aspiration (EUS-FNA), when possible.

RESULTS

SINK biopsy provided tissue samples that were sufficient for definite histologic diagnosis in 13 of 14 cases (diagnostic yield 92.8%). There were 8 gastric GI stromal tumors. In 7 of 8, the size of SINK specimens allowed immunohistochemical analysis, and the evaluation of malignant potential was carried out by means of mitotic index determination in 5 cases (71.42%). SINK biopsies determined the pathological diagnosis of all (4 of 4) nonmesenchymal lesions. Eight patients underwent both EUS-FNA and SINK, with final histologic diagnosis determined in 6 of 8 cases (75%) by SINK versus 1 of 8 cases (12.5%) by EUS-FNA (Fisher exact test, P = .023). There were no procedure-related complications.

LIMITATIONS

A single-center, retrospective analysis with small sample size.

CONCLUSION

SINK biopsy appears to be an easy, safe, and effective technique for determining the definitive pathological diagnosis, evaluation of the malignant potential, and planning management of SETs. It could be a reliable alternative to conventional FNA, providing larger samples that improve the histologic yield.

Digital image analysis is a useful adjunct to endoscopic ultrasonographic diagnosis of subepithelial lesions of the gastrointestinal tract

OBJECTIVE

The purpose of this study was to explore the role of digital image analysis in differentiating endoscopic ultrasonographic (EUS) features of potentially malignant gastrointestinal subepithelial lesions (SELs) from those of benign lesions.

METHODS

Forty-six patients with histopathologically confirmed gastrointestinal stromal tumors (GISTs), carcinoids, and lipomas who had undergone EUS evaluation were identified from our database. Representative regions of interest (ROIs) were selected from the EUS images, and features were extracted by texture analysis. On the basis of these features, an artificial neural network (ANN) was built, trained, and internally validated by unsupervised learning followed by supervised learning. Outcomes were the performance characteristics of the ANN.

RESULTS

A total of 106, 111, and 124 ROIs were selected from EUS images of 8, 10, and 28 patients with lipomas, carcinoids, and GISTs, respectively. For each ROI, 228 statistical parameters were extracted and later reduced to the 11 most informative features by principal component analysis. After training with 50% of the data, the remainder of the data were used to validate the ANN. The model was "good" in differentiating carcinoids and GISTs, with area under the receiver operating characteristic curve (AUC) values of 0.86 and 0.89, respectively. The model was "excellent" in identifying lipomas correctly, with an AUC of 0.92.

CONCLUSIONS

Digital image analysis of EUS images is a useful noninvasive adjunct to EUS evaluation of SELs.

Diagnosis of subepithelial tumors in the upper gastrointestinal tract by endoscopic ultrasonography

Endoscopic ultrasonography (EUS) is the most accurate procedure for detecting and diagnosing subepithelial tumors, due to its higher sensitivity and specificity than other imaging modalities. EUS can characterize lesions by providing information on echogenic origin, size, borders, homogeneity, and the presence of echogenic or anechoic foci. Linear echoendoscopes, and recently also electronic radial echoendoscopes, can be used with color Doppler or power Doppler to assess the vascular signals from subepithelial masses, and thus permit the differentiation of vascular structures from cysts, as well as the assessment of the tumor blood supply. However, the diagnostic accuracy of EUS imaging alone has been shown to be low in subepithelial lesions with 3rd and 4th layers. It is also difficult to differentiate exactly between benign and malignant tumors and to gain an accurate picture of histology using EUS. On the other hands, EUS guided fine needle aspiration (EUS-FNA) can provide samples for cytologic or histologic analysis. Hypoechoic lesions of the 3rd and the 4th EUS layers, more than in 1 cm diameter are recommended, and histologic confirmation using endoscopic submucosal resection or EUS-FNA should be obtained when possible. Therefore, EUS-FNA plays an important role in the clinical management of subepithelial tumors. Furthermore improvements in endoscopic technology are expected to be more useful modalities in differential diagnosis and discrimination between benign and malignant subepithelial tumors.

Long-term outcomes of prophylactic endoscopic histoacryl injection for gastric varices with a high risk of bleeding

PURPOSE

Endoscopic histoacryl injection (EHI) is reported to be an effective treatment modality for bleeding gastric varices (GVs) but controversial as a prophylactic treatment for non-bleeding GVs because efficacy and safety have yet to be determined. The aim of this study was to evaluate safety and long-term outcomes of prophylactic EHI for non-bleeding GVs with a high risk of bleeding.

METHODS

Thirty-three patients (23 males/10 females, mean age 56.6 years old) with a high risk of gastric variceal bleeding (large tumorous (27), red color sign (14) or rapidly growing in size (1)) underwent EHI. According to the grade of GVs, 25 patients belonged to F3, seven to F2, and one to F1. In terms of the locations of GVs, four patients belonged to type IGV1, 21 to type GOV2, and eight to type GOV1.

RESULTS

Obliteration of GVs was achieved in all of the treated patients. Twenty-three patients required one session and ten needed more than two sessions to obliterate their GVs. A mean volume of histoacryl used per session was 2.0 ml. Complications related to the procedure included immediate bleeding in two patients and bacteremia in one patient. The mean duration of follow-up was 12.2 months and eradication of GVs was achieved in 21 (95%) of 22 patients who were followed-up more than 3 months. Index GVs recurred in three of 21 patients (14%) and re-bleeding in index GVs after EHI occurred in two of 26 patients (8%).

CONCLUSIONS

Prophylactic EHI can be a promising procedure for eradication of non-bleeding GVs in case with a high risk of bleeding.

Endoscopic enucleation for gastric subepithelial tumors originating in the muscularis propria layer

BACKGROUND

Subepithelial tumors (SETs) of the stomach are considered benign. However, they have the potential for malignant transformation, especially if they originate in the muscularis propria layer. This study aimed to determine the feasibility of endoscopic enucleation (EEN) for SETs in the muscularis propria layer and to evaluate the diagnostic efficacy and safety of EEN for SETs.

METHODS

A total of 65 lesions in 64 patients were eligible for inclusion in the study during the period between June 2006 and September 2009. En bloc enucleation using an insulated-tip knife and snare was attempted for removal of gastric SETs from the muscularis propria.

RESULTS

A total of 60 tumors were successfully resected by EEN (success rate, 92.3%). The mean tumor size, determined by endoscopic ultrasound, was 13.8 mm (range, 5-30 mm). A histologic diagnosis was obtained for 63 tumors (diagnostic yield, 96.9%), which was leiomyoma for 32 lesions, gastrointestinal stromal tumor for 26 tumors, and other for 5 tumors. The rate for complete resection in relation to the location of the lesion in the stomach was higher for the cardia, the mid/lower body (100%), and the high body (96%) than for the fundus (75%) or the antrum (50%, p=0.006). The rate of perforation was significantly higher for the fundus (50%) than for other locations (0% for the cardia and 4% for the high body) (p<0.001).

CONCLUSIONS

Endoscopic enucleation of gastric SETs originating in the muscularis propria layer was a safe and effective method for the histologic diagnosis and removal of small gastric SETs, especially those located in the cardia and the high body of the stomach.

[Controversies in the surgical treatment of primary gastrointestinal stromal tumours (GIST)]

It is estimated that 50% of GIST are located at the time of their diagnosis. A complete surgical resection can be performed in up to 95% of these cases, making this the most important prognostic factor. This surgery must fulfil a series of technical requirements so as to be really effective, as it has to be R0, with no tumour rupture, with preservation of the pseudo-capsule, etc. Although the majority of GIST are gastric, their location in other anatomical areas, such as the oesophagus, duodenum or rectum, require the surgeon to use more complex techniques. Laparoscopy is increasingly used; however, we must avoid its use, due to there being few experienced groups or if there are large tumours. The use of neoadjuvant therapy has revived great interest by allowing to resection tumours that were once non-resectable or in very compromised anatomical locations, with less aggressive surgery. The use of pre-surgical biopsy is not exempt from serious risks, thus it should only be used for establishing a neoadjuvant treatment or if there are diagnostic doubts with other diseases in high risk patients.

Clinical course of subepithelial lesions detected on upper gastrointestinal endoscopy

AIM: To evaluate the natural history of subepithelial lesions.

METHODS: We reviewed the medical records of 104 159 patients who underwent upper gastrointestinal endoscopy at the Center for Health Promotion of Samsung Medical Center between 1996 and 2003. Subepithelial lesions were detected in 795 patients (0.76%); 252 patients were followed using upper gastrointestinal endoscopy for 82.5 ± 29.2 mo (range, 12-160 mo; median, 84 mo; 1st quartile, 60 mo; 3rd quartile, 105 mo). The median interval of follow-up endoscopy was 12 mo (range, 6-105 mo; 1st quartile, 12 mo; 3rd quartile, 24 mo).

RESULTS: The mean patient age was 53 years (range, 22-80 years), and the male-to-female ratio was 2.36:1 (177/75). The lesion size at initial measurement averaged 8.9 mm (range, 2-25 mm; median, 8 mm; 1st quartile, 5 mm; 3rd quartile, 10 mm). Of the 252 lesions, 244 (96.8%) were unchanged and 8 (3.2%) were significantly increased in size (from 12.9 ± 6.0 to 21.2 ± 12.2 mm) after a mean interval of 59.1 ± 27.5 mo (range, 12-86 mo). Surgical resection of lesions was performed when the lesions were ≥ 3 cm in diameter. Two lesions were diagnosed as gastrointestinal stromal tumors with an intermediate or high risk of malignancy and one lesion was classified as a schwannoma.

CONCLUSION: Most small subepithelial lesions do not change as shown by endoscopic examination, and regular follow-up with endoscopy may be considered in small, subepithelial lesions, especially lesions < 1 cm in size.

Endoscopic partial resection with the unroofing technique for reliable tissue diagnosis of upper GI subepithelial tumors originating from the muscularis propria on EUS (with video)

BACKGROUND

There is a growing body of evidence that a pathological diagnosis is necessary for small (<3 cm in diameter), asymptomatic, hypoechoic, subepithelial tumors (SETs) originating from the muscularis propria on EUS. However, the diagnostic efficacy of current tissue sampling techniques appears to be limited.

OBJECTIVE

To evaluate the diagnostic yield and safety of endoscopic partial resection using the unroofing technique (EPR-UT) in a subset of patients.

DESIGN

A prospective case series.

SETTING

A single tertiary-care referral center.

PATIENTS

Between August 2007 and March 2009, 16 patients with hypoechoic SETs of <3 cm in diameter, originating from the muscularis propria on EUS (14 gastric and 2 esophageal lesions), underwent EPR-UT.

INTERVENTIONS

The overlying mucosa was removed by using the unroofing technique using a conventional snare with electrical current to expose the tumor sufficiently. Next, the exposed tumor was partially resected by snaring.

MAIN OUTCOME MEASUREMENTS

The diagnostic yield and safety of this method.

RESULTS

EPR-UT provided specimens that were sufficient for a diagnosis and the assessment of risk for malignancy in 15 out of 16 cases (diagnostic yield 93.7% [95% CI, 80.4%-100.0%]). The pathological diagnoses were leiomyoma (7 of 15, 46.6%), GI stromal tumor (6 of 15, 40.0%), aberrant pancreas (1 of 15, 6.6%), and well-differentiated neuroendocrine carcinoma (1 of 15, 6.6%). Six cases with GI stromal tumor were classified as very low risk for malignant potential (mitotic index <5/50 high-power fields). Procedural blood oozing was relatively common (9 of 16, 56.0% [95% CI, 33.0%-77.0%]); however, this minor complication was easily controlled by argon plasma coagulation. There were no procedure-related major complications (0 of 16, 0% [95% CI, 0.0%-23.0%]).

LIMITATIONS

Single-center, noncomparative study with small sample size.

CONCLUSION

EPR-UT appears to be simple, safe, and effective for determining the definite pathological diagnosis and assessing malignant potential of small, hypoechoic SETs originating from the muscularis propria on EUS.

The natural history of gastrointestinal subepithelial tumors arising from muscularis propria: an endoscopic ultrasound survey

AIM

The majority of lesions originating from muscularis propria of stomach, duodenum, and colon are gastrointestinal stromal tumors (GISTs). Surgery is indicated when endosonographic criteria of malignancy are met, but little is known about the natural history of lesions with benign endosonographic features. Aim of this study was to evaluate the natural course of benign-appearing lesions originating from muscularis propria in organs where GISTs significantly overcome leiomyomas.

MATERIALS AND METHODS

A total of 49 asymptomatic patients with hypoechoic lesions originating from the fourth layer of the gastrointestinal tract entered a follow-up program by means of endoscopic ultrasonography. All lesions were nonulcerated, <3 cm in maximal diameter, with regular margins, and cystic spaces of <3 mm.

RESULTS

After a mean follow-up of 31+/-20.8 months and a median of 2 (range, 1 to 5) endosonographies/patient, no change in echostructure or dimensions was seen in 44 subjects whereas in 5, an increase of at least 25% in 1 diameter occurred. Surgical removal was proposed to all: 1 patient refused (she is still alive and symptom-free after 4 y), 3 of the 4 lesions removed proved to be GISTs with very low or low risk of malignancy and 1 lesion was classified as a glomus tumor with no malignant appearance.

CONCLUSIONS

Even small and benign-appearing lesions from muscularis propria may increase in size over time but this increase cannot be considered as an index of malignancy. As most of these lesions are GISTs, a policy of surveillance is advisable.

The role of endosonography in submucosal tumours

Submucosal tumours (SMTs) are relatively common findings in patients undergoing endoscopy, especially in upper gastrointestinal (GI) tract. This term includes various non-neoplastic and neoplastic conditions. Endoscopic ultrasonography (EUS) is the best imaging procedure to characterise SMT and to determine the need for further explorations. In this review, the following issues will be addressed: the endosonographic features of SMT; the diagnostic accuracy of EUS; the ability of EUS to distinguish benign and malignant SMTs; the value of EUS-guided fine-needle aspiration (FNA); and the influence of EUS on clinical management.

The natural history of upper gastrointestinal subepithelial tumors: a multicenter endoscopic ultrasound survey

GOALS

To evaluate the natural course of <3-cm upper gastrointestinal subepithelial tumors by endoscopic ultrasound (EUS) and to determine the appropriate timing for EUS follow-up.

BACKGROUND

Subepithelial tumors (SETs) can range from benign lesions to tumors with malignant behavior or potential to become malignant such as gastrointestinal stromal tumors (GISTs). EUS is considered a valuable tool for their evaluation as it estimates the exact size and layer of origin, and also additional morphologic features that can suggest the diagnosis. For high surgical risk patients and when no worrisome EUS features are seen, EUS surveillance of subepithelial tumors is often used.

METHODS

Fifty-one patients (mean age, 61.2+/-11.8 y; median, 63 y) with asymptomatic <3-cm SETs of second and fourth echolayer were followed for a mean period of 29.7 months (range, 3 to 84; median, 23 mo) in 3 tertiary care institutions. Evaluation included location, echolayer, tumor diameter, internal echo pattern, and outer margin of lesions by EUS. EUS was performed by using miniprobes, radial and linear echoendoscopes.

RESULTS

Follow-up revealed increase in size and/or change in echogenic features in 7/51 (13.7%) patients. Surgical follow-up was available for 3 of 7 of these patients. Two of the fourth layer SETs, which had both increase in size and change in echogenicity were found to be GISTs (+c-kit).

CONCLUSIONS

The majority of <3-cm SETs does not change during a median of 23 months. The change in echogenicity and increase in size may indicate a GIST.

EUS-guided FNA for the diagnosis of GI stromal cell tumors: sensitivity and cytologic yield

BACKGROUND

EUS-guided FNA has been well documented to aid in the diagnosis of subepithelial lesions by providing cytologic material. Studies to date evaluating the sensitivity of EUS-FNA for the diagnosis of GI stromal cell tumors (GIST) have been small, and few have relied on surgical histologic diagnosis as the reference standard.

OBJECTIVE

Our purpose was to determine the diagnostic yield and sensitivity of EUS-FNA for the diagnosis of GIST and to identify EUS features of GIST that are predictive of the ability to obtain adequate tissue by EUS-FNA.

DESIGN

All patients with histologically confirmed, c-kit-positive GIST who underwent EUS-FNA from 1998 to 2006 were reviewed. EUS images were examined for mass size, shape, location, wall layer, heterogeneity, echogenicity, cystic spaces, lobulation, ulceration, and central umbilication. Needle gauge, number of needle passes, and presence of a cytologist during the EUS-FNA were recorded.

RESULTS

A total of 37 patients (29 with diagnostic FNA cytology; 8 with nondiagnostic cytology) met the inclusion criteria. The diagnostic yield and sensitivity of EUS-FNA cytology for the diagnosis of GIST was 78.4% (29/37). The sensitivity was 84.4% (27/32) for GISTs located in the stomach, but poor for lesions located in the duodenum because none of these tumors yielded diagnostic cytology (n = 3). An increase in size up to 10 cm, round/oval shape, and identification of the origin of GIST within a specific sonographic wall layer were statistically significant in their ability to predict adequate tissue yield.

CONCLUSIONS

The sensitivity of EUS-FNA cytology for the diagnosis of GIST is 78.4% and is influenced by size, location, shape, and layer of origin.

Double-balloon enteroscopy and small bowel tumors: a South-European single-center experience

Small bowel tumors are rare, accounting for 1-2% of all gastrointestinal neoplasms. We sought to determine the diagnostic and therapeutic impact of double-balloon enteroscopy (DBE) in patients with small bowel tumors. Between January 2005 and March 2008, 78 patients underwent 96 DBE. All nine patients (seven males; mean age 68 +/- 11.3 years) with small bowel tumors were retrospectively reviewed. Clinical presentation was: mid-gastrointestinal bleeding or iron-deficient anemia (55.6%); abdominal pain (22.2%); nausea/vomiting and abdominal distension (22.2%). Five patients had abnormal findings in previous capsule endoscopy and four in previous radiologic examinations. Route of insertion was exclusively oral and abnormal lesions were detected in all patients (jejunum 8; ileum 1). Biopsies were taken in seven patients and provided definitive histological diagnosis in all except one. There were no complications of DBE. Surgical resection took place in eight patients. Final histologic diagnosis were: primary carcinoma (33.3%), gastrointestinal stromal tumor (GIST) (33.3%), malignant lymphoma (22.2%), and carcinoid tumor (11.1%). Mean follow-up time was 15.4 +/- 12.7 months (range 2-34 months). Six patients were submitted to chemotherapy. Two patients died. Small bowel tumors are common in patients submitted to DBE. Given its safety and diagnostic capabilities, DBE should be considered the gold-standard method in the study of these neoplasms.

A guide for the diagnosis and management of gastrointestinal stromal cell tumors

Gastrointestinal stromal cell tumors (GISTs) are the most common mesenchymal neoplasm of the gastrointestinal tract and are frequently detected on routine endoscopy. Although only approximately 10-30% of GISTs are clinically malignant, all may have some degree of malignant potential. Preoperative determination of malignancy risk can be estimated from tumor size and location, but reliable histopathologic criteria are not currently available. Given such biological uncertainty, accurate diagnosis is essential to differentiate these lesions from other truly benign, subepithelial tumors. Endoscopic ultrasound-guided fine-needle aspiration has emerged as an important procedure to secure a tissue diagnosis of a GIST. When encountering GISTs, gastroenterologists are faced with challenging management decisions, especially in the face of small, incidentally discovered lesions. The majority of localized GISTs are managed via surgical resection, although a select few may be observed using serial endoscopic ultrasound examinations. This Review provides a general overview of GISTs, with an emphasis on their endoscopic diagnosis, the management of localized disease, and the management of incidentally discovered GISTs.

Diagnosis and management of GI stromal tumors by EUS-FNA: a survey of opinions and practices of endosonographers

BACKGROUND

There is no consensus regarding the best management strategy for diagnosing and treating GI stromal tumors (GISTs).

OBJECTIVE

Our purpose was to examine the practice patterns of endosonographers in diagnosing and managing GISTs, particularly features of GISTs suggestive of malignancy, features that prompt surgical referral, and surveillance patterns.

DESIGN

An invitation to complete an online survey was e-mailed to all 413 members of the American Society for Gastrointestinal Endoscopy EUS Special Interest Group.

RESULTS

A total of 134 (32%) members responded; 59% of respondents use EUS features combined with FNA findings to diagnose GIST, and 89% consider a c-kit-positive stain on FNA most suggestive of GIST. However, 60% would diagnose GIST when cytologic samples are insufficient for diagnosis, and 40% would diagnose GIST if cytologic samples are sufficient but c-kit is negative. A total of 92% use size as the main criterion to distinguish benign from malignant GISTs, and 90% refer lesions >5 cm for surgery. For lesions not resected, 70% survey annually, 19% less than annually, 10% more than annually, and 1% do not survey.

LIMITATIONS

The opinions of the respondents do not necessarily reflect the opinions and practices of endosonographers nationwide. There are inherent limitations to an online multiple-choice survey, including low response rates.

CONCLUSIONS

There are substantial practice variations in diagnosing, resecting, and surveying GISTs. A majority of our survey respondents have made the diagnosis of GIST without FNA confirmation. Size >5 cm is the feature used most to predict malignancy and to prompt surgical referral. Surveillance practices for unresected GISTs are variable. Evidence is needed to establish practice guidelines in this area.

Simultaneous use of laparoscopy and endoscopy for minimally invasive resection of gastric subepithelial masses - analysis of 93 interventions

BACKGROUND

Subepithelial gastric tumors are common findings during upper gastrointestinal endoscopy. Tumor resection is mostly done laparoscopically, but there is still discussion concerning the size of lesion for which the treatment may be minimally invasive; additionally there is very little data available concerning patient outcome after minor access surgery.

METHODS

Clinicopathologic features and survival data of 93 consecutive patients undergoing a combined laparoscopic-endoscopic approach for gastric submucosal tumors were prospectively analyzed. Analysis included preoperative diagnostic work-up, perioperative data, and postoperative complications. Follow-up was carried out for patients with GIST to check for tumor recurrence.

RESULTS

It was possible to resect 88 of 93 lesions by the laparoscopic-endoscopic approach, with tumor-free margins in all patients. Intraoperative endoscopy facilitated exact tumor localization in 92 patients. Most lesions were removed by endoscopic-laparoscopic wedge resection or, less frequently, by a combined transgastric approach. Mean operative time was 90.7 min; the postoperative hospitalization was 7.3 days. Adverse events appeared in 7.5%, and conversion to open surgery was required in 6.5%. For patients suffering from gastrointestinal stromal tumors, there was no tumor recurrence at a mean follow-up of 40 months.

CONCLUSIONS

Combined laparoscopic-endoscopic "rendez-vous" procedures are easy to perform and offer a curative approach for almost all gastric submucosal lesions. The technique is associated with low morbidity and short hospitalization. Though even patients with large GISTs of intermediate and high risk were treated, no tumor recurrence has been observed to date.

[Endocrine tumor arising in heterotopic gastric pancreas]

We report the case of a 49-year-old caucasian woman, in whom an endocrine tumor arising in gastric heterotopic pancreas was diagnosed. The patient was treated surgically with a gastric wedge resection. Heterotopic pancreas is a benign anatomic condition, probably widely underdiagnosed because usually asymptomatic. The malignant transformation of aberrant pancreas is very rare and almost always in adenocarcinoma. The endocrine tumors developed in heterotopic pancreas are exceedingly rare. Of our knowledge, only four cases have been published and only one case in the gastric location similar to this reported case.

Subepithelial mass lesions in the upper gastrointestinal tract

The finding of a mass lesion in the upper gastrointestinal tract at endoscopy with apparent normal overlying mucosa is common. The differential diagnosis of such lesions is broad and includes those of intramural or extramural origin. Endoscopic ultrasound provides accurate imaging of subepithelial mass lesions and characterizes them according to size, echogenicity, and origin including the histologic layer if the lesion is intramural which narrows the differential diagnosis. Endoscopic ultrasound allows a guided tissue sample to be obtained for histologic confirmation which is especially important for hypoechoic lesions arising from the 3rd or 4th echogenic layers. The purpose of this article is to review the diagnosis of the more common subepithelial mass lesions with an emphasis on endoscopic ultrasound and the subsequent management or monitoring.

Gastric full-thickness suturing during EMR and for treatment of gastric-wall defects (with video)

BACKGROUND

The endoscopic full-thickness Plicator device was initially developed to provide an endoscopic treatment option for patients with GERD. Because the endoscopic full-thickness Plicator enables rapid and easy placement of transmural sutures, comparable with surgical sutures, we used the Plicator device for endoscopic treatment or prevention of GI-wall defects.

OBJECTIVE

To describe the outcomes and complications of endoscopic full-thickness suturing during EMR and for the treatment of gastric-wall defects.

DESIGN

A report of 4 cases treated with the endoscopic full-thickness suturing between June 2006 and April 2007.

SETTING

A large tertiary-referral center.

PATIENTS

Four subjects received endoscopic full-thickness suturing. The subjects were women, with a mean age of 67 years.

INTERVENTIONS

Of the 4 subjects, 3 received endoscopic full-thickness suturing during or after an EMR. One subject received endoscopic full-thickness suturing for treatment of a fistula.

MAIN OUTCOME MEASUREMENTS

Primary outcome measurements were clinical procedural success and procedure-related adverse events.

RESULTS

The mean time for endoscopic full-thickness suturing was 15 minutes. In all cases, GI-wall patency was restored or ensured, and no procedure-related complications occurred. All subjects responded well to endoscopic full-thickness suturing.

LIMITATIONS

The resection of one GI stromal tumor was incomplete. Because of the Plicator's 60F distal-end diameter, endoscopic full-thickness suturing could only be performed with the patient under midazolam and propofol sedation. The durable Plicator suture might compromise the endoscopic follow-up after EMR.

CONCLUSIONS

The endoscopic full-thickness Plicator permits rapid and easy placement of transmural sutures and seems to be a safe and effective alternative to surgical intervention to restore GI-wall defects or to ensure GI-wall patency during EMR procedures.