Experience of endoscopic ultrasound in staging adenocarcinoma of the cardia

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.

Prognostic Implications of Tumor Differentiation in Clinical T1N0 Gastric Adenocarcinoma

Background

Current guidelines recommend neoadjuvant chemotherapy in patients with locoregional gastric adenocarcinoma. Patients diagnosed with early stage gastric adenocarcinoma are usually managed with upfront surgical intervention. However, pathologic staging in a subset of these clinically staged patients identifies more advanced locoregional disease requiring adjuvant treatment. Therefore, identifying these patients prior to surgical intervention is critical to ensure employment of the appropriate treatment paradigm. The aim of the current study was to define patient characteristics associated with clinical understaging in early gastric cancer.

Methods

Using the National Cancer Database (2004–2014) we identified 3,892 individuals with clinical T1N0 gastric adenocarcinoma who underwent upfront definitive surgery, had negative surgical margins, and did not receive preoperative chemotherapy or radiotherapy. Patient characteristics were compared between those with pathologic stage T1N0 disease and those who were upstaged upon surgery.

Results

Twenty‐seven percent of clinical T1N0 gastric adenocarcinomas had a change in stage because of pathologically defined ≥T2 disease or positive lymph nodes. Individuals who were upstaged had a higher tumor grade compared with those with pathologic stage T1N0 disease. Specifically, 41.9% (530/1,264) of individuals with a poorly differentiated tumor were upstaged, compared with only 10.7% (70/656) with a well‐differentiated tumor. Approximately 75% of cases involved upstaging because of T misclassification. The highest percentage of upstaging was shown for tumors located at the fundus and body of the stomach.

Conclusion

Upstaging of clinical T1N0 gastric adenocarcinoma is characterized by higher tumor grade and is mostly a result of a change in T stage. These findings mandate thorough workup in order to identify patients with clinically staged T1N0 disease requiring preoperative chemotherapy.

Implications for Practice

Upstaging of clinical T1N0 gastric adenocarcinoma is characterized by higher tumor grade and is mostly a result of a change in T stage. These findings mandate thorough workup in order to identify patients with clinically staged T1N0 disease requiring preoperative chemotherapy.

This article evaluates the frequency of upstaging following surgery among cT1N0 gastric cancer and defines the corresponding patient characteristics, with the goal of better identifying those patients who require preoperative chemotherapy.

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.

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.

Lymph node metastasis of gastric cancer

Despite a decrease in incidence in recent decades, gastric cancer is still one of the most common causes of cancer death worldwide [1]. In areas without screening for gastric cancer, it is diagnosed late and has a high frequency of nodal involvement [1]. Even in early gastric cancer (EGC), the incidence of lymph node (LN) metastasis exceeds 10%; it was reported to be 14.1% overall and was 4.8 to 23.6% depending on cancer depth [2]. It is important to evaluate LN status preoperatively for proper treatment strategy; however, sufficient results are not being obtained using various modalities. Surgery is the only effective intervention for cure or long-term survival. It is possible to cure local disease without distant metastasis by gastrectomy and LN dissection. However, there is no survival benefit from surgery for systemic disease with distant metastasis such as para-aortic lymph node metastasis [3]. Therefore, whether the disease is local or systemic is an important prognostic indicator for gastric cancer, and the debate continues over the importance of extended lymphadenectomy for gastric cancer. The concept of micro-metastasis has been described as a prognostic factor [4-9], and the biological mechanisms of LN metastasis are currently under study [10-12]. In this article, we review the status of LN metastasis including its molecular mechanisms and evaluate LN dissection for the treatment of gastric cancer.

Quality indicators of surgery for adenocarcinoma of the esophagus and gastroesophageal junction

Surgical treatment of adenocarcinoma of the esophagus and gastroesophageal junction is complex and challenging. Huge variation exist in the immediate and long term outcomes of such interventions and it is generally accepted that this is a direct consequence of the experience of the surgical team. However beside surgical quality many other indicators of quality management may influence outcome. Definition of the gastroesophageal junction remains controversial and the performance of staging procedures i.e. CT scan, endoscopy and fine needle aspiration, PET scan still suboptimal. As a result there is disagreement on the selection of patients for surgery, type of surgical approach in particular in relation to the extent of lymph node dissection as well as the extent of esophageal and/or gastric resection. In the design of randomized controlled trials comparing primary surgery versus multimodality treatment surgical quality criteria are notoriously lacking. It therefore remains a matter of debate which patients eventually will benefit from primary surgery versus those who will benefit from induction therapy. A lack of surgical quality indicators is also very prominent when assessing the value of new surgical technologies such as minimally invasive surgery or robotic surgery. Improvements in this wide spectrum of aspects is mandatory and will certainly be of great value to further improve both short and long term outcome after surgery for these complex cancers.

Potential of Surface-Coil MRI for Staging of Esophageal Cancer

OBJECTIVE

The aim of this pilot study was to assess the feasibility of external surface-coil MRI as a new method of imaging the esophagus and esophageal cancer.

CONCLUSION

The results for the 10 patients investigated indicate that by using a high-resolution axial T2-weighted sequence (small field of view, thin section images), MRI provides detailed imaging of the anatomic layers of the esophageal wall and tumor. Three independent radiologists found good correlation in the morphologic appearance and extent of tumor between MRI and matched histology sections. This study illustrates the potential of the technique as an alternative form of local staging for esophageal cancer.

Evaluation of Siewert classification in gastro-esophageal junction adenocarcinoma: What is the role of endoscopic ultrasonography?

BACKGROUND

Preoperative assessment of gastro-esophageal junction (GEJ) adenocarcinoma stage and its location according to Siewert are essential for planning the therapeutic approach. The present study was aimed at analyzing the utility of endoscopic ultrasonography (EUS) in evaluating GEJ adenocarcinoma stage and whether this modality added to EGD improves assessment of Siewert type.

METHODS

The results of 51 patients studied by EGD plus EUS (EGD/EUS group) were compared with the results of 54 patients studied by EGD only (EGD group).

RESULTS

A differentiation of pT1 tumors was attempted by measurement of the tumor length using 4 cm as a criterion. This goal was not achieved because of a high rate of advanced tumors less than 4 cm (sensitivity and specificity were 81.3% and 34.2%, respectively). Conversely EUS ability in pT1 assessment was very reliable (92%). The accuracy in defining the Siewert type was 72.5% and 64.8% for EGD/EUS and EGD groups, respectively (P = 0.394). Some difficulties in distinguishing between type II and III tumors were observed in both groups with an extremely low specificity (44%) in classifying type II tumors by EGD group.

CONCLUSIONS

EUS seems to be essential in differentiating pT1 from advanced tumors. It shows an accuracy in defining the Siewert type of 72.5%, with some difficulties in distinguishing from type II and III tumors.

Endoscopic ultrasound for luminal malignancies

Luminal gastrointestinal (GI) tract cancers are responsible for substantial morbidity and mortality. Since the first pairing of ultrasonography with endoscopy in 1980, technologic advances and the increased availability of trained endosonographers have propelled endoscopic ultrasonography (EUS) to the forefront of luminal GI cancer staging. In this article we discuss the role of EUS for evaluating luminal GI cancers.

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

BACKGROUND

The feasibility of a less invasive operation for early stage cancer of the gastric cardia with a low frequency of lymph node involvement has been previously demonstrated by us. Precise discrimination among mucosal, submucosal, and advanced cancers, as well as accurate evaluation of the proximal tumor margin are prerequisites for such stage-specific treatment. EUS is considered the most reliable staging modality. However, there is no EUS study specifically of cardia cancer.

METHODS

Forty-five patients with gastric cardia cancer who underwent gastrectomy with at least first-tier lymphadenectomy were retrospectively analyzed. The results of preoperative linear-array echoendoscopy (7.5 MHz) with respect to cancer depth, lymph node involvement, and esophageal invasion were compared with postoperative histopathologic findings.

RESULTS

Overall diagnostic accuracy for depth of invasion was 71%. Sensitivity for T1, T2, and T3 lesions was 100%, 31% and 75%, respectively. Overstaging of T2 cancers was the main diagnostic error. Mucosal (pT1-m) and submucosal (pT1-sm) cancers were correctly discriminated in 81% of patients. Diagnostic accuracy for lymph node involvement was 80%. EUS had positive and negative predictive values of 90% and 80%, respectively, for esophageal invasion.

CONCLUSIONS

For gastric cardia cancer, the linear-array echoendoscope yielded satisfactory results with respect to depth of invasion, lymph node involvement, and esophageal invasion evaluation. The information obtained is useful to the performance of stage-specific treatment.

Intraoperative US staging of T in gastric cancer: final results of a blind prospective study

BACKGROUND

In order to improve the accuracy in the assessment of depth of tumor invasion, we performed an ultrasound examination of the resected specimen intraoperatively just after removal by the surgeon (Intraoperative Ultrasonography (IUS). This prospective blind study reports the results obtained with the IUS in the staging of T in a group of 281 patients who underwent curative gastrectomy for gastric cancer.

METHODS

After the removal by the surgeon, the portion of the stomach harboring the tumor was submitted to ultrasonography with a linear 7.5 Mhz probe. An echo-free standoff pad was placed between the probe and the organ; a second echo-free standoff pad was interposed between the stomach and the support surface. The diagnosis of depth of invasion was based on the degree of disruption of the five-layer sonographic structure of the gastric wall.

RESULTS

The IUS staging of T corresponded to the pathological diagnosis in 256 out of 281 cases (overall accuracy 91.1%). The sensitivity in the different classes of T was, respectively, 91.2 in T1m cases, 83.3 in the T1sm cases, 89.6 in the T2 cases, and 93.5% in the T3 cases.

CONCLUSION

The IUS on the resected specimen has a high degree of accuracy in the assessment of depth of tumor invasion and seems to be an important advance in the clinical staging of gastric cancer.

Surgical treatment of gastric cancer invading the oesophagus

INTRODUCTION

There is controversy regarding which type of surgical treatment is most appropriate for upper gastric cancer invading the oesophagus.

METHODS

A review of the pertinent literature was carried out regarding oesophageal involvement in gastric cancer.

RESULTS

Invasion of the oesophagus occurred in 26-63% of Western surgical series. It was more frequent in Borrmann IV type, linitis plastica, pT3-pT4, diffuse type by Lauren, N+ or tumours exceeding 5 cm in diameter. Lymphatic tumour spread was caudad (coeliac nodes, hepatoduodenal nodes, paraortic nodes) but mediastinal nodes were also involved if tumour growth in the oesophagus exceeded 3 cm or if there was transmural oesophageal infiltration. In Western countries there was less than 30% 5-year survival and no long-term survivors when hepatoduodenal or mediastinal nodes were metastatic. Mediastinal dissection through thoracotomy did not provide any benefit.

CONCLUSIONS

A rational approach involves total gastrectomy plus partial oesophagectomy. Abdominal transhiatal resection may be performed in the case of a localized, non-infiltrating tumour and oesophageal involvement <2 cm. However, infiltrating, poorly differentiated or Borrmann III-IV tumours require a right thoracotomy to achieve a longer margin of clearance. When oesophageal involvement is >3 cm, or hepatoduodenal or mediastinal nodes are positive, no surgical procedure is curative and the literature demonstrates that extended aggressive surgery has no benefits.