Accuracy of linear-array EUS for preoperative staging of gastric cardia cancer

Linear EUS Accuracy in Preoperative Staging of Gastric Cancer: A Retrospective Multicenter Study

INTRODUCTION

Preoperative gastric cancer (GC) staging is the most reliable prognostic factor that affects therapeutic strategies. Contrast-enhanced computed tomography (CECT) and radial endoscopic ultrasound (R-EUS) scans are the most commonly used staging tools for GC. The accuracy of linear EUS (L-EUS) in this setting is still controversial. The aim of this retrospective multicenter study was to evaluate the accuracy of L-EUS and CECT in preoperative GC staging, with regards to depth of tumor invasion (T staging) and nodal involvement (N staging).

MATERIALS AND METHODS

191 consecutive patients who underwent surgical resection for GC were retrospectively enrolled. Preoperative staging had been performed using both L-EUS and CECT, and the results were compared to postoperative staging by histopathologic analysis of surgical specimens.

RESULTS

L-EUS diagnostic accuracy for depth of invasion of the GC was 100%, 60%, 74%, and 80% for T1, T2, T3, and T4, respectively. CECT accuracy for T staging was 78%, 55%, 45%, and 10% for T1, T2, T3, and T4, respectively. L-EUS diagnostic accuracy for N staging of GC was 85%, significantly higher than CECT accuracy (61%).

CONCLUSIONS

Our data suggest that L-EUS has a higher accuracy than CECT in preoperative T and N staging of GC.

Comparison of diagnostic accuracy between linear EUS and miniprobe EUS for submucosal invasion in suspected early gastric cancer

OBJECTIVE

This study assessed the accuracy of linear endoscopic ultrasound (EUS) in diagnosing submucosal (SM) invasion and compared linear EUS with mini-probe EUS in suspected early gastric cancer (EGC) patients.

METHODS

Patients diagnosed with biopsy-verified suspected EGC were analysed retrospectively. They were all examined by linear EUS or miniprobe EUS for preoperative diagnosis of invasion depth and underwent endoscopic or surgical treatment for radical resection. The invasion depth evaluated by EUS and pathology were categorized into no invasion of SM and invasion of SM or deeper. We compared the diagnosis of EUS with postoperative pathology results.

RESULTS

A total of 105 patients were included in the final analysis. We found that the overall prediction accuracy of linear EUS (n = 57) for SM invasion in suspected EGC was higher than that of mini-probe EUS (n = 48), but no statistically significant differences were noted (82.5% vs 72.9%, p = 0.344). The negative predictive value (NPV) of linear EUS was significantly higher than that of mini-probe EUS (100% vs 82.8%, p = 0.037). The binary logistic regression analysis identified that tumor size (p = 0.036), the presence of ulceration (p < 0.001) and the EUS type (p = 0.027) were independent risk factors for the diagnosis of SM invasion by EUS. The area under the receiver operating curve (ROC) was 0.889 and 0.719 for linear and mini-probe EUS, respectively.

CONCLUSION

Linear EUS diagnosed suspected EGC for SM invasion with higher accuracy than mini-probe EUS. Additionally, large and ulcerative lesions may lead to overestimation.

Significance of Lymph Node Metastasis in the Treatment of Gastric Cancer and Current Challenges in Determining the Extent of Metastasis

The stomach exhibits abundant lymphatic flow, and metastasis to lymph nodes is common. In the case of gastric cancer, there is a regularity to the spread of lymph node metastasis, and it does not easily metastasize outside the regional nodes. Furthermore, when its extent is limited, nodal metastasis of gastric cancer can be cured by appropriate lymph node dissection. Therefore, identifying and determining the extent of lymph node metastasis is important for ensuring accurate diagnosis and appropriate surgical treatment in patients with gastric cancer. However, precise detection of lymph node metastasis remains difficult. Most nodal metastases in gastric cancer are microscopic metastases, which often occur in small-sized lymph nodes, and are thus difficult to diagnose both preoperatively and intraoperatively. Preoperative nodal diagnoses are mainly made using computed tomography, although the specificity of this method is low because it is mainly based on the size of the lymph node. Furthermore, peripheral nodal metastases cannot be palpated intraoperatively, nodal harvesting of resected specimens remains difficult, and the number of lymph nodes detected vary greatly depending on the skill of the technician. Based on these findings, gastrectomy with prophylactic lymph node dissection is considered the standard surgical procedure for gastric cancer. In contrast, several groups have examined the value of sentinel node biopsy for accurately evaluating nodal metastasis in patients with early gastric cancer, reporting high sensitivity and accuracy. Sentinel node biopsy is also important for individualizing and optimizing the extent of uniform prophylactic lymph node dissection and determining whether patients are indicated for function-preserving curative gastrectomy, which is superior in preventing post-gastrectomy symptoms and maintaining dietary habits. Notably, advancements in surgical treatment for early gastric cancer are expected to result in individualized surgical strategies with sentinel node biopsy. Chemotherapy for advanced gastric cancer has also progressed, and conversion gastrectomy can now be performed after downstaging, even in cases previously regarded as inoperable. In this review, we discuss the importance of determining lymph node metastasis in the treatment of gastric cancer, the associated difficulties, and the need to investigate strategies that can improve the diagnosis of lymph node metastasis.

Linear-array endoscopic ultrasound improves the accuracy of preoperative submucosal invasion prediction in suspected early gastric cancer compared with radial endoscopic ultrasound: A prospective cohort study

BACKGROUND AND AIM

There is a lack of literature comparing linear endoscopic ultrasound (EUS) and radial EUS for the prediction of the depth of invasion in early gastric cancer (EGC). The aim of this study is to evaluate the accuracy of linear EUS for the diagnosis of submucosal (SM) invasion and compare linear EUS with radial EUS in suspected EGC patients.

METHODS

Seventy-two consecutive patients with suspected EGC who underwent a preoperative assessment using linear EUS or radial EUS were prospectively enrolled. The depth of invasion was categorized into mucosal to SM (< T1b) and SM or deeper (≥ T1b), and the EUS-determined diagnosis was compared with postoperative histopathological findings.

RESULTS

Thirty-nine patients underwent radial EUS, and 33 patients underwent linear EUS examination. The baseline characteristics between the groups were well balanced. The diagnostic accuracy was much higher for patients who underwent linear EUS compared with radial EUS (90.9% vs 69.2%, P = 0.024). The sensitivity was 92.3% (95% confidence interval [CI] 66.7-98.6%) for linear EUS and 90.9% (95% CI 62.3-98.4%) for radial EUS. The specificity was 90.0% (95% CI 69.9-97.2%) in the linear EUS group, while the specificity was 60.7% (95% CI 42.4-76.4%) in the radial EUS group. Univariate analysis showed that EUS type (odds ratio 0.225, 95% CI 0.057-0.884, P = 0.033) was an associated risk factor of incorrect T1b staging in EGC patients. The area under the receiver operating curve was 0.912 and 0.758 for linear and radial EUS, respectively.

CONCLUSION

Linear EUS was more accurate for determining SM invasion and therapeutic strategy in suspected EGC patients compared with radial EUS.

A Meta-Analysis And Systematic Review Of Accuracy Of Endoscopic Ultrasound For N Staging Of Gastric Cancers

BACKGROUND

Endoscopic ultrasonography (EUS) is widely used as a staging modality for gastric cancer. However, the results of studies on the use of EUS for N staging in gastric cancer vary. This study aimed at studying the overall diagnostic accuracy of EUS for N staging of gastric cancer.

METHODS

Published studies were identified through searching the MEDLINE, Web of Science, EMBASE, SpringerLink and ScienceDirect databases. A bivariate random effect model was used to estimate the sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR). A hierarchical summary receiver operating characteristic curves (HSROC) based on the pooled data was also computed.

RESULTS

Fifty studies (5223 patients) were included in this analysis. The pooled sensitivity, specificity, PLR, NLR and DOR of EUS for N staging were 0.82 (95% CI 0.78 to 0.85), 0.68 (0.63 to 0.73), 2.6 (2.2 to 3.0), 0.27 (0.22 to 0.32), and 10 (8 to 12), respectively. The area under the HSROC was 0.83.

CONCLUSION

The EUS may provide a clinically useful tool to guide physicians in the N staging of gastric cancer. However, physicians must note that the EUS has a relatively low specificity.

What should be known prior to performing EUS exams? (Part II)

In “What should be known prior to performing EUS exams, Part I,” the authors discussed the need for clinical information and whether other imaging modalities are required before embarking EUS examinations. Herewith, we present part II which addresses some (technical) controversies how EUS is performed and discuss from different points of view providing the relevant evidence as available. (1) Does equipment design influence the complication rate? (2) Should we have a standardized screen orientation? (3) Radial EUS versus longitudinal (linear) EUS. (4) Should we search for incidental findings using EUS?

Endoscopic ultrasonography compared with multidetector computed tomography for the preoperative staging of gastric cancer: a meta-analysis

Background

The current study sought to perform a meta-analysis to compare the preoperative staging of endoscopic ultrasonography (EUS) and multidetector computed tomography (MDCT) in gastric carcinoma.

Methods

Articles published between January 1, 2000, and April 1, 2016, that compared EUS with MDCT were included, and data were presented as 2 × 2 tables. The sensitivities, specificities and summary receiver operating characteristic (ROC) curves for T and N staging were calculated using a bivariate mixed effects model. Data were weighted by generic variance and then pooled by random-effects modeling.

Results

Eight studies comprising 1736 patients were included in this meta-analysis. For T1 staging, the sensitivity value for EUS (82%) was significantly higher than that for MDCT (41%) (relative risk (RR): 2.06, 95% confidence interval (CI) 1.07–3.94; P = 0.030). For lymph node involvement, the sensitivity value for EUS (91%) was also significantly higher than that for MDCT (77%) (RR 1.14, 95% CI 1.05–1.23; P = 0.001). However, the specificity values of both EUS and MDCT were quite low, at 49 and 63%, respectively. No significant differences in T2–4 staging between EUS and MDCT were noted.

Conclusion

This meta-analysis indicates that EUS may be superior to MDCT in preoperative T1 and N staging. Additionally, the low specificity values of EUS and MDCT for N staging merits attention.

Clinical Outcomes of Endoscopic Submucosal Dissection for Adenocarcinoma of the Esophagogastric Junction

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) for adenocarcinoma in the esophagogastric junction (EGJ) is a technically difficult procedure. We analyzed the long-term clinical outcomes of ESD for adenocarcinoma in the EGJ to determine the feasibility of this treatment approach.

METHODS

Subjects who underwent ESD for Siewert type II adenocarcinoma between December 2004 and December 2011 were eligible for this study. Clinical features and treatment outcomes were retrospectively reviewed using medical records.

RESULTS

A total of 88 subjects underwent ESD at our institute. The median patient age was 66 years (interquartile range [IQR] 59-71 years), and the male-to-female ratio was 10.0:1. The median tumor diameter was 20 mm (IQR 14-25 mm), and the median procedure time was 40 min (IQR 30-60 min). Adverse events occurred in nine patients (10.2 %), namely bleeding (n = 6) and suspicious microperforation (n = 3). En bloc, complete, and curative resection rates were 88.6 % (78/88), 83.0 % (73/88), and 60.2 % (53/88), respectively. In multivariate analysis, undifferentiated histology (P = 0.009) and elevated lesions (P = 0.011) were factors associated with noncurative resection. During a median follow-up period of 68.5 months, local tumor recurrence was detected in two patients (2.4 %), and the 5-year overall and disease-specific survival rates were 96.6 and 100.0 %, respectively.

CONCLUSIONS

ESD for the treatment of EGJ cancer may be an effective and safe treatment strategy based on favorable long-term outcomes.

Endoscopic ultrasonography is not required for staging malignant esophageal strictures that preclude the passage of a diagnostic gastroscope

BACKGROUND AND AIM

Endoscopic ultrasound (EUS) is considered the most sensitive modality for local staging of esophageal cancer (ECA) and current guidelines recommend EUS in all patients with non-metastatic disease. Our aim was to identify a subset of patients with stenotic, non-metastatic ECA who will not benefit from staging EUS.

METHODS

This multicenter study evaluated consecutive patients with newly diagnosed non-metastatic ECA referred for local staging by EUS. All patients had endoscopic evaluation of malignant strictures with 9.8/9.9-mm diagnostic gastroscope prior to EUS. Main outcome measure was to evaluate the relationship between degree of malignant stenosis and tumor staging by EUS.

RESULTS

Of 100 patients (median age, 65 years; male 81%), gastroscope could not be advanced past the stricture in 46, all of whom (100%) had locally advanced disease at EUS: T3N0/N+ in 39 and T4N0/N+ in seven. Echoendoscope could not traverse the stricture in any of these patients. Gastroscope could be advanced through the stricture in 54 patients in whom EUS staging was T1N0 in five, T2N0/N+ in eight and T3N0/N+ in 41; echoendoscope could not pass through the stricture in 24 of these 54 (44.4%) patients, all of whom had T3N0/N+ disease. On logistic regression analysis, inability to pass a gastroscope through the stricture was significantly associated with advanced (T3/4) tumor stage (OR = 28.7, 95% CI = 1.64-501.2; P = 0.021).

CONCLUSION

Routine EUS examination may not be required in all patients with ECA as the inability to advance a diagnostic gastroscope past a malignant stricture correlates 100% with locally advanced disease on EUS.

Diagnostic accuracy of endoscopic ultrasonography (EUS) for the preoperative locoregional staging of primary gastric cancer

BACKGROUND

Endoscopic ultrasound (EUS) is proposed as an accurate diagnostic device for the locoregional staging of gastric cancer, which is crucial to developing a correct therapeutic strategy and ultimately to providing patients with the best chance of cure. However, despite a number of studies addressing this issue, there is no consensus on the role of EUS in routine clinical practice.

OBJECTIVES

To provide both a comprehensive overview and a quantitative analysis of the published data regarding the ability of EUS to preoperatively define the locoregional disease spread (i.e., primary tumor depth (T-stage) and regional lymph node status (N-stage)) in people with primary gastric carcinoma.

SEARCH METHODS

We performed a systematic search to identify articles that examined the diagnostic accuracy of EUS (the index test) in the evaluation of primary gastric cancer depth of invasion (T-stage, according to the AJCC/UICC TNM staging system categories T1, T2, T3 and T4) and regional lymph node status (N-stage, disease-free (N0) versus metastatic (N+)) using histopathology as the reference standard. To this end, we searched the following databases: the Cochrane Library (the Cochrane Central Register of Controlled Trials (CENTRAL)), MEDLINE, EMBASE, NIHR Prospero Register, MEDION, Aggressive Research Intelligence Facility (ARIF), ClinicalTrials.gov, Current Controlled Trials MetaRegister, and World Health Organization International Clinical Trials Registry Platform (WHO ICTRP), from 1988 to January 2015.

SELECTION CRITERIA

We included studies that met the following main inclusion criteria: 1) a minimum sample size of 10 patients with histologically-proven primary carcinoma of the stomach (target condition); 2) comparison of EUS (index test) with pathology evaluation (reference standard) in terms of primary tumor (T-stage) and regional lymph nodes (N-stage). We excluded reports with possible overlap with the selected studies.

DATA COLLECTION AND ANALYSIS

For each study, two review authors extracted a standard set of data, using a dedicated data extraction form. We assessed data quality using a standard procedure according to the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) criteria. We performed diagnostic accuracy meta-analysis using the hierarchical bivariate method.

MAIN RESULTS

We identified 66 articles (published between 1988 and 2012) that were eligible according to the inclusion criteria. We collected the data on 7747 patients with gastric cancer who were staged with EUS. Overall the quality of the included studies was good: in particular, only five studies presented a high risk of index test interpretation bias and two studies presented a high risk of selection bias.For primary tumor (T) stage, results were stratified according to the depth of invasion of the gastric wall. The meta-analysis of 50 studies (n = 4397) showed that the summary sensitivity and specificity of EUS in discriminating T1 to T2 (superficial) versus T3 to T4 (advanced) gastric carcinomas were 0.86 (95% confidence interval (CI) 0.81 to 0.90) and 0.90 (95% CI 0.87 to 0.93) respectively. For the diagnostic capacity of EUS to distinguish T1 (early gastric cancer, EGC) versus T2 (muscle-infiltrating) tumors, the meta-analysis of 46 studies (n = 2742) showed that the summary sensitivity and specificity were 0.85 (95% CI 0.78 to 0.91) and 0.90 (95% CI 0.85 to 0.93) respectively. When we addressed the capacity of EUS to distinguish between T1a (mucosal) versus T1b (submucosal) cancers the meta-analysis of 20 studies (n = 3321) showed that the summary sensitivity and specificity were 0.87 (95% CI 0.81 to 0.92) and 0.75 (95% CI 0.62 to 0.84) respectively. Finally, for the metastatic involvement of lymph nodes (N-stage), the meta-analysis of 44 studies (n = 3573) showed that the summary sensitivity and specificity were 0.83 (95% CI 0.79 to 0.87) and 0.67 (95% CI 0.61 to 0.72), respectively.Overall, as demonstrated also by the Bayesian nomograms, which enable readers to calculate post-test probabilities for any target condition prevalence, the EUS accuracy can be considered clinically useful to guide physicians in the locoregional staging of people with gastric cancer. However, it should be noted that between-study heterogeneity was not negligible: unfortunately, we could not identify any consistent source of the observed heterogeneity. Therefore, all accuracy measures reported in the present work and summarizing the available evidence should be interpreted cautiously. Moreover, we must emphasize that the analysis of positive and negative likelihood values revealed that EUS diagnostic performance cannot be considered optimal either for disease confirmation or for exclusion, especially for the ability of EUS to distinguish T1a (mucosal) versus T1b (submucosal) cancers and positive versus negative lymph node status.

AUTHORS' CONCLUSIONS

By analyzing the data from the largest series ever considered, we found that the diagnostic accuracy of EUS might be considered clinically useful to guide physicians in the locoregional staging of people with gastric carcinoma. However, the heterogeneity of the results warrants special caution, as well as further investigation for the identification of factors influencing the outcome of this diagnostic tool. Moreover, physicians should be warned that EUS performance is lower in diagnosing superficial tumors (T1a versus T1b) and lymph node status (positive versus negative). Overall, we observed large heterogeneity and its source needs to be understood before any definitive conclusion can be drawn about the use of EUS can be proposed in routine clinical settings.

Appraisal of staging endoscopic ultrasonography in a modern high-volume esophageal program

BACKGROUND

Accurate pretreatment staging is essential to decision making for patients with esophageal and junctional cancers, particularly when choosing endoscopic therapy or a multimodal approach. As the efficacy of endoscopic ultrasonography (EUS) has been reported as variable, we assessed it prospectively in a large cohort from a high-volume center.

METHODS

The EUS data from 2007 to 2011 were reviewed and analyzed. We conducted a comparative analysis with computed tomography-positron emission tomography (CT-PET) staging and pathology. Survival was analyzed by Kaplan-Meier testing on EUS-predicted T- and N-stage cohorts.

RESULTS

Altogether, 222 patients underwent EUS. Among patients undergoing primary surgical resection, preoperative EUS diagnosed the T stage correctly in 71 % (55/77) of cases. Sensitivity and specificity for T1, T2, and T3 tumors were 94 and 89 %, 55 and 80 %, and 66 and 93 %, respectively. Mean maximum standard uptake volume on CT-PET correlated moderately with the EUS T stage (r = 0.42, p < 0.0001). EUS accuracy for nodal disease was 65 %. Survival was statistically better for the EUS T1 group than for those with T3 tumors (p = 0.01). Nodal metastases diagnosed on EUS predicted a significantly worse prognosis than EUS-negative nodes on both univariate and multivariate analyses (p < 0.0001 and p = 0.005 respectively).

CONCLUSIONS

There was a significant relation between EUS T and N stages and overall survival. EUS demonstrated 71 % accuracy for the overall T stage. Staging accuracy of EUS for large lesions was less effective than for T1 tumors, underlining the need for a multimodal investigative approach to stage esophageal tumors accurately.

Low accuracy of endoscopic ultrasonography for detailed T staging in gastric cancer

Background

The accuracy of endoscopic ultrasonography (EUS) for preoperative staging of gastric cancer varies. The aim of this study was to investigate the accuracy of EUS tumor (T) and node (N) staging, and to identify the histopathological factors influencing accuracy based on the detailed tumor depth of gastric cancer.

Methods

In total, 309 patients with gastric cancer with confirmed pathological staging underwent EUS examination for preoperative staging at Seoul St. Mary’s Hospital, Korea, between January and December 2009. The T and N staging of EUS and the pathologic report were compared.

Results

The overall accuracies of EUS for T stage and the detailed T stages were 70.2% and 43.0%, respectively. In detailed stage, tumors greater than 50 mm in diameter were significantly associated with T overstaging (odds ratio (OR) = 2.094). The overall accuracy of EUS for N staging was 71.2%. Tumor size (20 mm ≤ size < 50 mm, OR = 4.389; and 50 mm ≤ size, OR = 8.170), cross-sectional tumor location (circumferential, OR = 4.381) and tumor depth (submucosa, OR = 3.324; muscular propria, OR = 6.923; sub-serosa, OR = 4.517; and serosa-exposed, OR = 6.495) were significant factors affecting incorrect nodal detection.

Conclusions

Careful attention is required during EUS examination of large-sized gastric cancers to increase accuracy, especially for T staging.

A systematic review and meta-analysis of the utility of EUS for preoperative staging for gastric cancer

BACKGROUND

Accurate preoperative staging is important in determining the appropriate treatment of gastric cancer. Recently, endoscopic ultrasound (EUS) has been introduced as a staging modality. However, reported test characteristics for EUS in gastric cancer vary. Our purpose in this study was to identify, synthesize, and evaluate findings from all articles on the performance of EUS in the preoperative staging of gastric cancer.

METHODS

Electronic literature searches were conducted using Medline, Embase, and the Cochrane Central Register of Controlled Trials from 1 January 1998 to 1 December 2009. All search titles and abstracts were independently rated for relevance by a minimum of two reviewers. Meta-analysis for the performance of EUS was analyzed by calculating agreement (Kappa statistic), and pooled estimates of accuracy, sensitivity, and specificity for all EUS examinations, using histopathology as the reference standard. Subgroup analyses were also performed.

RESULTS

Twenty-two articles met our inclusion criteria and were included in the review. EUS pooled accuracy for T staging was 75% with a moderate Kappa (0.52). EUS was most accurate for T3 disease, followed by T4, T1, and T2. EUS pooled accuracy for N staging was 64%, sensitivity was 74%, and specificity was 80%. There was significant heterogeneity between the included studies. Subgroup analyses found that annual EUS volume was not associated with EUS T and N staging accuracy (P = 0.836, 0.99, respectively).

CONCLUSION

EUS is a moderately accurate technique that seems to describe advanced T stage (T3 and T4) better than N or less advanced T stage. Stratifying by EUS annual volume did not affect EUS performance in staging gastric cancer.

EUS for the staging of gastric cancer: a meta-analysis

BACKGROUND

The role of EUS in the locoregional staging of gastric carcinoma is undefined.

OBJECTIVE

We aimed to comprehensively review and quantitatively summarize the available evidence on the staging performance of EUS.

DESIGN

We systematically searched the MEDLINE, Cochrane, CANCERLIT, and EMBASE databases for relevant studies published until July 2010.

SETTING

Formal meta-analysis of diagnostic accuracy parameters was performed by using a bivariate random-effects model.

PATIENTS

Fifty-four studies enrolling 5601 patients with gastric cancer undergoing disease staging with EUS were eligible for the meta-analysis.

MAIN OUTCOME MEASUREMENTS

EUS staging accuracy across eligible studies was measured by computing overall sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR).

RESULTS

EUS can differentiate T1-2 from T3-4 gastric cancer with high accuracy, with overall sensitivity, specificity, PLR, NLR, and DOR of 0.86 (95% CI, 0.81-0.90), 0.91 (95% CI, 0.89-0.93), 9.8 (95% CI, 7.5-12.8), 0.15 (95% CI, 0.11-0.21), and 65 (95% CI, 41-105), respectively. In contrast, the diagnostic performance of EUS for lymph node status is less reliable, with overall sensitivity, specificity, PLR, NLR, and DOR of 0.69 (95% CI, 0.63-0.74), 0.84 (95% CI, 0.81-0.88), 4.4 (95% CI, 3.6-5.4), 0.37 (95% CI, 0.32-0.44), and 12 (95% CI, 9-16), respectively. Results regarding single T categories (including T1 substages) and Bayesian nomograms to calculate posttest probabilities for any target condition prevalence are also provided.

LIMITATIONS

Statistical heterogeneity was generally high; unfortunately, subgroup analysis did not identify a consistent source of the heterogeneity.

CONCLUSIONS

Our results support the use of EUS for the locoregional staging of gastric cancer, which can affect the therapeutic management of these patients. However, clinicians must be aware of the performance limits of this staging tool.

Has the accuracy of preoperative diagnosis improved in cases of early-stage gastric cancer?

BACKGROUND

Adequate preoperative evaluation for gastric cancer staging is essential to develop an individualized treatment strategy involving surgery with reduced lymphadenectomy and laparoscopic gastrectomy.

METHODS

A total of 509 gastric cancer patients with clinical Stage IA or IB disease were divided into two groups: 304 patients were admitted in 2000 or earlier (Group A), and 205 patients were admitted in 2001, when multidetector computed tomography (MD-CT) was available, or later (Group B). We evaluated the accuracy of the preoperative diagnoses of tumor depth, lymph node involvement, and tumor stage.

RESULTS

With respect to tumor depth, 94.5 and 52.8% of patients were staged correctly in cT1 and cT2 patients, respectively. Among both cT1 and cT2 patients, the underestimated rates were lower in Group B than in Group A. For nodal metastasis, 83.2 and 30.0% of patients were staged correctly in cN0 and cN1 patients, respectively. Among the cN0 patients, 82.1 and 84.7% of Group A and Group B patients, respectively, were staged correctly. Among the cN1 patients, none of the patients in Group B was underestimated, while 9.7% of Group A patients were underestimated. There was a significant increase in the percentage of correctly staged patients and a decrease in the percentage of underestimated patients in Group B in comparison to Group A in both cStage IA and cStage IB patients.

CONCLUSIONS

Remarkable advances have been observed in the accuracy of preoperative staging in the early stage of gastric cancer. However, it is necessary to continue to develop accurate preoperative and intraoperative diagnostic systems.

R0 resection in the treatment of gastric cancer: Room for improvement

Gastric carcinoma is one of the most frequent malignancies in the world and its clinical behavior especially depends on the metastatic potential of the tumor. In particular, lymphatic metastasis is one of the main predictors of tumor recurrence and survival, and current pathological staging systems reflect the concept that lymphatic spread is the most relevant prognostic factor in patients undergoing curative resection. This is compounded by the observation that two-thirds of gastric cancer in the Western world presents at an advanced stage, with lymph node metastasis at diagnosis. All current therapeutic efforts in gastric cancer are directed toward individualization of therapeutic protocols, tailoring the extent of resection and the administration of preoperative and postoperative treatment. The goals of all these strategies are to improve prognosis towards the achievement of a curative resection (R0 resection) with minimal morbidity and mortality, and better postoperative quality of life.

Prognostic value of preoperative clinical staging assessed by computed tomography in resectable gastric cancer patients: a viewpoint in the era of preoperative treatment

BACKGROUND

In the era of pre- or perioperative therapy for gastric cancer, clinical staging before treatment appears to be increasingly important for prognosis, yet there are no data on the subject for resectable gastric cancer patients.

OBJECTIVES

To evaluate the prognostic role of preoperative locoregional staging in gastric cancer patients undergoing curative resection.

METHODS

We reviewed 1964 gastric cancer patients who underwent curative resection without preoperative therapy from 2001 to 2005. We performed computed tomography and clinical staging according to both the International Union Against Cancer (UICC)/American Joint Committee on Cancer (AJCC) (sixth edition) classification system, which bases N stage on the number of involved nodes, and the Japanese Classification of Gastric Carcinoma (JCGC) system, which bases N stage on node location.

RESULTS

The 5-year survival rates for patients with clinical T1, T2, T3, and T4 disease were 94.5%, 83.6%, 57.7%, and 35.5%, respectively (P < 0.001). The 5-year survival rates were 89.4% and 68.3%, respectively, for patients with clinical UICC/AJCC N0 and N1 disease (P < 0.001) and 89.4%, 72.4%, 61.0%, and 41.9%, respectively, for patients with clinical JCGC n0, n1, n2, and n3 disease (P < 0.001). When the JCGC system was applied within the UICC/AJCC N1 category, the 5-year survival rates significantly decreased, going from n1 (72.4%) to n2 (61.0%) to n3 (38.2%) (P < 0.001). In multivariate analysis, clinical T and N stage remained significant prognostic factors for overall survival.

CONCLUSIONS

Clinical stage is an independent predictor of long-term survival in the preoperative setting. It should be incorporated as a stratification factor in a randomized clinical trial of preoperative therapy for gastric cancer patients.

Diagnostic accuracy of T and N stages with endoscopy, stomach protocol CT, and endoscopic ultrasonography in early gastric cancer

BACKGROUND

Preoperative accurate diagnosis of the T and N stages in early gastric cancer (EGC) is important in determining the application of various limited treatments. The aim of this study is to analyze the accuracy of T and N staging of EGC with esophagogastroduodenoscopy (EGD), Stomach protocol CT (S-CT), and endoscopic ultrasonography (EUS), and the factors influencing the accuracy.

METHODS

Four hundred and thirty-four patients preoperatively diagnosed as EGC using EGD or S-CT and undergoing curative gastrectomy at Seoul National University Hospital in 2005 were included. The T and N stage reviewed by experienced personnel were compared with the surgical pathology.

RESULTS

The predictive values for EGC of EGD, S-CT, and EUS were 87.4%, 92.2%, and 94.1%, respectively. The predictive values for node negativity of S-CT, and EUS were 90.1% and 92.6%, respectively. The factors leading to underestimation of T stage with EGD were the upper third location, the size greater than 2 cm, and diffuse type of tumor. Those with S-CT were female sex, the upper third location and lesion size greater than 2 cm.

CONCLUSIONS

Before applying limited treatment for EGC, a surgeon should consider the risk factors of underestimation of T stage with EGD or S-CT.

Outcome in relation to numbers of nodes harvested in lymph node-positive gastric cancer

AIMS

We conducted a retrospective case-control study to compare the prognostic differences of lymph node-positive gastric cancer patients between dissected lymph nodes (DLNs) <15 group and DLNs > or =15 group.

METHODS

A retrospective study of 323 lymph node-positive gastric patients who underwent potentially curative resection for gastric cancer was analyzed to identify the prognostic differences between DLNs <15 group and DLNs > or =15 group. Of these patients, 49 patients with <15 DLNs were matched with 147 patients with > or =15 DLNs according to gender, age, location of primary tumor, and type of gastrectomy.

RESULTS

Patients with n1 lymph node metastasis (according to JCGC), serosal involvement, ratio of positive lymph nodes less than 25%, or without adjuvant chemotherapy in > or =15 DLN group had comparatively longer median survival than patients with homologous clinicopathologic variables in <15 DLN group, respectively. Patients with n1 stage lymph node metastasis, serosal involvement, non-intestinal Lauren classification, or without adjuvant chemotherapy in <15 DLN group had higher recurrence rate than patients with homologous clinicopathologic variables in > or =15 DLN group, respectively. In addition, we demonstrated that patients with more than n1 stage lymph node metastasis in <15 DLN group had higher rate of peritoneal dissemination than those with more than n1 lymph node metastasis in > or =15 DLN group.

CONCLUSIONS

DNL > or =15 was an important factor to improve the prognosis of lymph node-positive gastric cancer patients after potential curative resection.

Adenocarcinoma of the esophagogastric junction: the role of abdominal-transhiatal resection

The surgical strategy for adenocarcinoma of the esophagogastric junction is still controversial. The aim of this study was to evaluate surgical results of the abdominal-transhiatal approach for 100 consecutively operated type II and III cardia adenocarcinoma, to clarify clinicopathological differences between these tumors, and to define prognostic factors. A prospectively maintained database identified 100 consecutively operated patients with Siewert type II and III cardia adenocarcinoma. Survival was analyzed by the Kaplan-Meier method. Differences between subgroups and prognostic factors were evaluated by the log rank test and Cox regression. Concerning clinicopathological characteristics, only the incidence of T1-2 stage was significantly higher in Siewert II type (P = .006). A complete (R0) resection was obtained in 74 patients (74%). Overall postoperative mortality and morbidity rates were 6% and 28%, respectively. Overall actuarial 5-year survival rate in resected patients was 27.4% (median 27 months), with 20.6% for type II and 34 for type III cancers (P = .07). Considering R0 resections, overall actuarial 5-year survival rate was 33.9% (median 33 months), with 26.7% for type II and 40.5 for type III cancer (P = .06). Pathologic T and N stage and R status were independent prognostic factors by multivariate analysis, and Siewert type showed a trend toward significance. The abdominal-transhiatal approach is a safe surgical approach, allowing complete tumor resection and adequate lymphadenectomy in these patients. True carcinoma of the cardia may be a distinct clinical entity with a more aggressive natural history than subcardial gastric carcinoma.

Endoscopic ultrasound and computed tomography in restaging and predicting prognosis after neoadjuvant chemotherapy in patients with locally advanced gastric cancer

BACKGROUND

The objective of the current study was to assess the staging accuracy and prognostic role of preoperative endoscopic ultrasound (EUS) and computed tomography (CT) in patients with locally advanced gastric cancer (LAGC) after neoadjuvant chemotherapy.

METHODS

Presurgical LAGC patients underwent EUS and CT before and after 3 cycles of neoadjuvant chemotherapy. Chemotherapy was comprised of docetaxel (at a dose of 36 mg/m(2)) and cisplatin (at a dose of 40 mg/m(2)) on Days 1 and 8 of a 3-week cycle.

RESULTS

Forty patients were enrolled in the study. After chemotherapy, the accuracy of EUS and CT was found to be 47% and 57%, respectively for T classification (P = .22) and 39% and 37%, respectively for N classification (P > .99). The 3-year overall survival (OS) rate for patients downstaged with EUS for T and/or N classification was greater than that for nondownstaged patients (69% vs 41%; P = .05). The 2-year recurrence-free survival (RFS) rate was also better for the EUS-downstaged patients than for the nondownstaged patients (77% vs 47%; P = .04). On multivariate analysis, EUS downstaging was found to be correlated with OS (hazards ratio [HR] of 0.12; P = .04), and was correlated with RFS with borderline statistical significance (HR of 0.27; P = .07). The differences in OS and RFS between the patients downstaged with CT and those not downstaged were not found to be statistically significant.

CONCLUSIONS

Restaging by EUS and CT after neoadjuvant chemotherapy in patients with LAGC was found to be inaccurate. However, T and/or N downstaging by EUS was found to be correlated with better OS and RFS. Thus, downstaging by EUS may be a useful clinical parameter with which to predict a better outcome for LAGC patients.

Effect of lymphadenectomy extent on advanced gastric cancer located in the cardia and fundus

AIM: To analyze the prognostic impact of lymphade-nectomy extent in advanced gastric cancer located in the cardia and fundus.

METHODS: Two hundred and thirty-six patients with advanced gastric cancer located in the cardia and fundus who underwent D2 curative resection were analyzed retrospectively. Relationships between the numbers of lymph nodes (LNs) dissected and survival was analyzed among different clinical stage subgroups.

RESULTS: The 5-year overall survival rate of the entire cohort was 37.5%. Multivariate prognostic variables were total LNs dissected (P < 0.0001; or number of negative LNs examined, P < 0.0001), number of positive LNs (P < 0.0001), T category (P < 0.0001) and tumor size (P = 0.015). The greatest survival differences were observed at cutoff values of 20 LNs resected for stage II (P = 0.0136), 25 for stage III(P < 0.0001), 30 for stage IV (P = 0.0002), and 15 for all patients (P = 0.0024). Based on the statistically assumed linearity as best fit, linear regression showed a significant survival enhancement based on increasing negative LNs for patients of stages III (P = 0.013) and IV (P = 0.035).

CONCLUSION: To improve the long-term survival of patients with advanced gastric cancer located in the cardia and fundus, removing at least 20 LNs for stage II, 25 LNs for stage III, and 30 LNs for stage IVpatients during D2 radical dissection is recommended.

How good is endoscopic ultrasound for TNM staging of gastric cancers? A meta-analysis and systematic review

AIM: To evaluate the accuracy of endoscopic ultrasound (EUS) for staging of gastric cancers.

METHODS: Only EUS studies confirmed by surgery were selected. Only studies from which a 2 × 2 table could be constructed for true positive, false negative, false positive and true negative values were included. Articles were searched in Medline, Pubmed, Ovid journals, Cumulative index for nursing & allied health literature, International pharmaceutical abstracts, old Medline, Medline nonindexed citations, and Cochrane control trial registry. Two reviewers independently searched and extracted data. The differences were resolved by mutual agreement. 2 × 2 tables were constructed with the data extracted from each study. Meta-analysis for the accuracy of EUS was analyzed by calculating pooled estimates of sensitivity, specificity, likelihood ratios, and diagnostic odds ratio. Pooling was conducted by both the Mantel-Haenszel method (fixed effects model) and DerSimonian Laird method (random effects model). The heterogeneity of studies was tested using Cochran’s Q test based upon inverse variance weights.

RESULTS: Initial search identified 1620 reference articles and of these, 376 relevant articles were selected and reviewed. Twenty-two studies (n = 1896) which met the inclusion criteria were included in this analysis. Pooled sensitivity of T1 was 88.1% (95% CI: 84.5-91.1) and T2 was 82.3% (95% CI: 78.2-86.0). For T3, pooled sensitivity was 89.7% (95% CI: 87.1-92.0). T4 had a pooled sensitivity of 99.2% (95% CI: 97.1-99.9). For nodal staging, the pooled sensitivity for N1 was 58.2% (95% CI: 53.5-62.8) and N2 was 64.9% (95% CI: 60.8-68.8). Pooled sensitivity to diagnose distant metastasis was 73.2% (95% CI: 63.2-81.7). The P for chi-squared heterogeneity for all the pooled accuracy estimates was > 0.10.

CONCLUSION: EUS results are more accurate with advanced disease than early disease. If EUS diagnoses advanced disease, such as T4 disease, the patient is 500 times more likely to have true anatomic stage of T4 disease.

Staging accuracy of esophageal cancer by endoscopic ultrasound: A meta-analysis and systematic review

AIM: To evaluate the accuracy of endoscopic ultrasound (EUS) in the staging of esophageal cancer.

METHODS: Only EUS studies confirmed by surgery were selected. Articles were searched in Medline and Pubmed. Two reviewers independently searched and extracted data. Meta-analysis of the accuracy of EUS was analyzed by calculating pooled estimates of sensitivity, specificity, likelihood ratios, and diagnostic odds ratio. Pooling was conducted by both the Mantel-Haenszel method (fixed effects model) and DerSimonian Laird method (random effects model). The heterogeneity of studies was tested using Cochran’s Q test based upon inverse variance weights.

RESULTS: Forty-nine studies (n = 2558) which met the inclusion criteria were included in this analysis. Pooled sensitivity and specificity of EUS to diagnose T1 was 81.6% (95% CI: 77.8-84.9) and 99.4% (95% CI: 99.0-99.7), respectively. To diagnose T4, EUS had a pooled sensitivity of 92.4% (95% CI: 89.2-95.0) and specificity of 97.4% (95% CI: 96.6-98.0). With Fine Needle Aspiration (FNA), sensitivity of EUS to diagnose N stage improved from 84.7% (95% CI: 82.9-86.4) to 96.7% (95% CI: 92.4-98.9). The P value for the χ² test of heterogeneity for all pooled estimates was > 0.10.

CONCLUSION: EUS has excellent sensitivity and specificity in accurately diagnosing the TN stage of esophageal cancer. EUS performs better with advanced (T4) than early (T1) disease. FNA substantially improves the sensitivity and specificity of EUS in evaluating N stage disease. EUS should be strongly considered for staging esophageal cancer.

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.

Changing trends in endosonography: linear imaging and tissue are increasingly the issue

The indications and uses of endoscopic ultrasound (EUS) are expanding. The role of EUS-guided fine needle aspiration (EUS-FNA) is considered an essential aspect of EUS practice. A significant change in the indications and technology used for EUS has occurred. This study was designed to compare the use of radial, linear, and miniprobe endosonography equipment during a 10-year period in a single, large, EUS practice. A retrospective review of an EUS experience at a single high-volume center was performed. In this single-center experience, there has been an increase in the volume of EUS and EUS-FNA. For luminal cancer-staging cases, the radial echoendoscope is the predominant scope used for examination and has not changed significantly. In contrast, for pancreaticobiliary and mediastinal indications, the use of the linear array echoendoscope alone has increased and currently is the preferred scope for examination (33% vs. 76%, P < 0.001; 46% vs. 96%, P < 0.001). In these cases requiring EUS-FNA, the use of the linear array scope alone has increased from 17% to 73%. In this single-center experience, EUS has shifted from an imaging technology to an image-guided biopsy and therapeutic technology. The use of the linear array EUS alone has increased, especially in the evaluation of pancreatobiliary and mediastinal disease and when fine-needle aspiration is performed.

Accuracy of endoscopic ultrasound staging of gastric cancer in routine clinical practice in Singapore

OBJECTIVE

Endoscopic ultrasound has emerged as the leading modality to assess the T and N stage in gastric cancer. This study aimed to assess the accuracy of TN staging by endoscopic ultrasound in routine clinical practice in Singapore.

METHODS

Over a period of 7 years, 77 patients (male: 70%; median age 62.8 years) with gastric cancer underwent preoperative staging with endoscopic ultrasound. Fifty-seven patients eventually underwent surgery with tissues available for histopathological staging and comparison.

RESULTS

The tumor locations were: cardia: 13; corpus: 20; incisura: 19; antrum: 25. The majority was poorly differentiated (57.1%); 26% were moderately differentiated and 16.9% were well differentiated adenocarcinoma. Compared to pathological staging, the overall accuracy of T staging by endoscopic ultrasound was 77.2% (17.5% under-staged: 5.3% over-staged). The staging accuracy of T1 (92.9%) and T3 (81.8%) was higher than T2 (57.1%) and T4. For N staging, the accuracy of endoscopic ultrasound was 59.6% (26.3% under-staged; 14% over-staged); this was significantly superior to computer tomography (43.9%).

CONCLUSION

Endoscopic ultrasound is useful for the T staging of gastric cancer, with an overall accuracy rate of 77%, and up to 93% for T1 lesions. Under-staging may occur due to microscopic tumor infiltration, while over-staging may arise due to inflammatory reactions. The accuracy of N staging is lower at 60%, but could be further improved with the use of fine needle aspiration.

The useful combination of a higher frequency miniprobe and endoscopic submucosal dissection for the treatment of T1 esophageal cancer

BACKGROUND

There are few published data on the discrimination ability of endoscopic ultrasonography (EUS) among each subdivision of T1 cancer, and overdiagnosis is an unsolved problem that eventually causes overtreatment. The purpose of this study was to verify whether our treatment strategy incorporating EUS realizes a tailored patient management of T1 esophageal cancer.

METHODS

This study comprised 20 esophageal cancer patients undergoing 12- to 20-MHz miniprobes for T staging and a 7.5-MHz dedicated echoendoscope for N staging. Initial therapy constituted endoscopic submucosal dissection (ESD) for endosonographically node-negative, mucosal, or slight submucosal cancers and a primary esophagectomy with three-field lymphadenectomy for deeper cancers. If the ESD specimen revealed no cancer involvement of the muscularis mucosa, the patients entered a follow-up program; otherwise, they were advised to undergo a subsequent esophagectomy and three-field lymphadenectomy.

RESULTS

Perfect discrimination accuracy was achieved among T1, T2, and T3 cancers. Whether cancer depth was up to the slight submucosal layer or deeper was correctly differentiated in 12 of 14 T1 cancers (86%). EUS categorized all patients correctly into candidates for either ESD or surgery. The pathological cancer depth of the resected specimens revealed that no patients experienced unnecessary overtreatment.

CONCLUSIONS

A higher frequency miniprobe is useful for the detailed evaluation of cancer depth, contributing to decision making for treatment options of T1 esophageal cancer. A miniprobe and echoendoscope in combination with ESD provide an appropriately tailored management plan on an individual basis, avoiding unnecessary treatment or indicating radical surgery.

Usefulness of endoscopic ultrasonography in preoperative TNM staging of gastric cancer

AIM: To evaluate the value of endoscopic ultrasono-graphy (EUS) in the preoperative TNM staging of gastric cancer.

METHODS: Forty-one patients with gastric cancer (12 early stage and 29 advanced stage) proved by esophagogastroduodenoscopy and biopsies preoperatively evaluated with EUS according to TNM (1997) classification of International Union Contrele Cancer (UICC). Pentax EG-3630U/Hitachi EUB-525 echo endoscope with real-time ultrasound imaging linear scanning transducers (7.5 and 5.0 MHz) and Doppler information was used in the current study. EUS staging procedures for tumor depth of invasion (T stage) were performed according to the widely accepted five-layer structure of the gastric wall. All patients underwent surgery. Diagnostic accuracy of EUS for TNM staging of gastric cancer was determined by comparing preoperative EUS with subsequent postoperative histopathologic findings.

RESULTS: The overall diagnostic accuracy of EUS in preoperative determination of cancer depth of invasion was 68.3% (41/28) and 83.3% (12/10), 60% (20/12), 100% (5/5), 25% (4/1) for T1, T2, T3, and T4, respectively. The rates for overstaging and understaging were 24.4% (41/10), and 7.3% (41/3), respectively. EUS tended to overstage T criteria, and main reasons for overstaging were thickening of the gastric wall due to perifocal inflammatory change, and absence of serosal layer in certain areas of the stomach. The diagnostic accuracy of metastatic lymph node involvement or N staging of EUS was 100% (17/17) for N0 and 41.7% (24/10) for N+, respectively, and 66% (41/27) overall. Misdiagnosing of the metastatic lymph nodes was related to the difficulty of distinguishing inflammatory lymph nodes from malignant lymph nodes, which imitate similar echo features. Predominant location and distribution of tumors in the stomach were in the antrum (20 patients), and the lesser curvature (17 patients), respectively. Three cases were found as surgically unresectable (T4 N+), and included as being correctly diagnosed by EUS.

CONCLUSION: EUS is a useful diagnostic method for preoperative staging of gastric cancer for T and N criteria. However, EUS evaluation of malignant lymph nodes is still unsatisfactory.

Differences and similarities of adenocarcinomas of the esophagus and esophagogastric junction

During the last few decades there has been an alarming rise in the incidence of tumors originating at the esophagogastric junction (EGJ) [1]. The reason for this is unknown. Tumors of the EGJ can be categorized in two types of cancer divided according to their anatomical origin: distal esophageal adenocarcinoma and adenocarcinoma of the gastric cardia. However, due to their location, in the transitional zone of the esophagus and stomach, there is constant debate about the proper classification, staging, and management of these tumors. The etiology of distal esophageal adenocarcinoma is clearly related to gastroesophageal reflux disease (GERD) and the development of a Barrett's esophagus [2]. The etiology of adenocarcinoma of the gastric cardia is less well understood. In the present paper, we will discuss the clinical characteristics and clinical management of esophagogastric tumors. Special attention will be given to differences and similarities of adenocarcinomas of the gastric cardia and distal esophagus.

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