Prognostic relevance of gastric cancer staging by endoscopic ultrasound

Predictive Value of Preoperative Endoscopic Ultrasound (EUS) After Neoadjuvant Chemotherapy in Locally Advanced Esophagogastric Cancer - Data From a Randomized German Phase II Trial

PURPOSE

The role of EUS before or after neoadjuvant chemotherapy (nCTX) in advanced esophagogastric cancer (EGC) is still unclear. The phase II NEOPECX trial evaluated perioperative chemotherapy with or without panitumumab in this setting. The aim of this sub-study was to investigate the prognostic value of EUS-guided preoperative staging before and after nCTX.

MATERIALS AND METHODS

Preoperative yuT/yuN stages by EUS were compared with histopathological ypT/ypN stages after curative resection. Reduction in T-stage from baseline to preoperative EUS was defined as downstaging (DS+) and compared to progression-free (PFS) and overall survival (OS) of patients without downstaging (DS-). In addition, preoperative EUS N-stages (positive N+ or negative N-) were correlated with clinical data.

RESULTS

The preoperative yuT-stage correlated with the ypT-stage in 48% of cases (sensitivity 48%, specificity 52%), while the preoperative yuN-stage correlated with the ypN-stage in 64% (sensitivity 76%, specificity 52%). Within DS+ patients who were downstaged by ≥ 2 T-categories, a trend towards improved OS was detected (median OS DS+: not reached (NR), median OS DS-: 38.5 months (M), p=0.21). Patients with yuN+ at preoperative EUS had a worse outcome than yuN- patients (median OS yuN-: NR, median OS yuN+: 38.5 M, p = 0.013).

CONCLUSION

The diagnostic accuracy of EUS to predict the response after nCTX in patients with advanced EGC is limited. In the current study the endosonographic detection of lymph node metastasis after nCTX indicates a poor prognosis. In the future, preoperative EUS with sectional imaging procedures may be used to tailor treatment for patients with advanced EGC.

A potential decision-making algorithm based on endoscopic ultrasound for staging early gastric cancer: a retrospective study

BACKGROUND

Clinical staging of gastric cancer (GC) before treatment is essential. Endoscopic ultrasound (EUS) is a recommended staging tool, but its efficacy remains controversial. Our previous prospective study evaluated the potential value of EUS for T staging and presented discrepancies. In this study, we aimed to evaluate the efficacy of EUS in T staging by comparing it with pathological staging. We analyze the factors that can potentially affect accuracy to identify suitable subgroups for EUS staging.

METHODS

Data from a total of 1763 consecutive patients with GC from January 2015 to December 2017 were analyzed. Results from EUS and pathological T staging were compared. The factors that might affect EUS's accuracy were analyzed.

RESULTS

The sensitivity, specificity, positive predictive value, and negative predictive value of EUS in patients with early GC were 62.08%, 96.13%, 90.94%, and 80.21%, respectively. The accuracy rates of uT1, uT2-uT4, and uT3-uT4 were 90.94%, 79.02%, and 78.39%, respectively. In multivariate analysis, underestimation was more likely to be observed in patients with tumors located in the middle or upper third of the stomach. Overestimation was more likely to be observed in patients with tumors located in the lower third or those without ulcer. Other factors affecting accuracy included ulcer, differentiation, larger size and undergoing surgery.

CONCLUSION

Our findings highlight the role of EUS in determining the T staging of GC. Overestimation and underestimation in T-staging were significantly associated with the tumor location in early GC, and a decision-making algorithm was proposed for clinical practice in early cancers based on these findings.

Potential key roles of tumour budding: a representative malignant pathological feature of non-small cell lung cancer and a sensitive indicator of prognosis

OBJECTIVES

To investigate the relationship between tumour budding, clinicopathological characteristics of patients and prognosis in non-small cell lung cancer.

STUDY DESIGN

A retrospective study was used.

PARTICIPANTS

We selected 532 patients with non-small cell lung cancer from China, including 380 patients with adenocarcinoma and 152 with squamous cell carcinoma.

PRIMARY AND SECONDARY OUTCOME MEASURES

Tumour budding was visible using H&E staining as well as pancytokeratin staining. The count data and measurement data were compared using the χ² test and the t-test, respectively. The overall survival rate was the follow-up result. The survival curves were drawn using the Kaplan-Meier method, and the differences between groups were analysed using the log-rank method. The independent prognostic factor of patients with lung cancer was determined using a multivariate Cox proportional hazard model.

RESULTS

In patients with lung adenocarcinoma, there was a correlation between tumour budding and spread through air spaces (OR 36.698; 95% CI 13.925 to 96.715; p<0.001), and in patients with squamous cell carcinoma, tumour budding state was closely related to the peritumoural space (OR 11.667; 95% CI 4.041 to 33.683; p<0.001). On Cox regression analysis, multivariate analysis showed that tumour budding, pleural and vascular invasion, spread through air spaces, tumour size, lymph node metastasis, and tumour node metastasis stage were independent risk factors of prognosis for patients with non-small cell lung cancer.

CONCLUSIONS

As an effective and simple pathological diagnostic index, it is necessary to establish an effective grading system in the clinical diagnosis of lung cancer to verify the value of tumour budding as a prognostic indicator. We hope that this analysis of Chinese patients with non-small cell lung cancer can provide useful reference material for the continued study of tumour budding.

Can endoscopic ultrasonography (EUS) improve the accuracy of clinical T staging by computed tomography (CT) for gastric cancer?

INTRODUCTION

With the introduction of new therapeutic options for gastric cancer treatment, more precise preoperative staging of gastric cancer is needed. The purpose of this study was to evaluate the role of endoscopic ultrasonography (EUS) for improving the accuracy of clinical T staging by computed tomography (CT) for gastric cancer.

MATERIALS AND METHODS

A total of 2636 patients underwent stomach protocol CT (S-CT) and EUS, followed by gastrectomy for primary gastric adenocarcinoma between September 2012 and February 2018 at Seoul National University Hospital. The results of preoperative S-CT and EUS were compared to the postoperative pathologic staging.

RESULTS

The overall accuracy of S-CT and EUS for T staging were 69.4% and 70.4%, respectively. When T staging was divided into T1-2 and T3-4 for clinically advanced gastric cancer (AGC), the positive predictive value for T3-4 using S-CT, EUS, and a combination of both modalities was 73.8%, 79.3%, and 85.6%, respectively. In 114 cases of indeterminate lesions between cT1 and cT2 by S-CT, EUS had a better prediction rate than the final decision based on endoscopy or the agreement between the two experts (Match rate: EUS vs. final decision, 69.3% vs. 58.8%).

CONCLUSION

EUS can be a complementary diagnostic tool to clinical T staging of gastric cancer by CT for selecting T3-4 lesion.

Clinical significance of endoscopic ultrasonography in diagnosing invasion depth of early gastric cancer prior to endoscopic submucosal dissection

BACKGROUND AND AIM

Endoscopic ultrasonography is a reliable diagnostic modality for determining indications of endoscopic submucosal dissection for early gastric cancer. We aimed to clarify the clinical significance of endoscopic ultrasonography in the invasion depth diagnosis of early gastric cancer.

METHODS

We retrospectively assessed 1598 consecutive patients with 2001 early gastric cancers who underwent EUS before ESD or surgery between October 2010 and April 2019 at our institution. Lesions were classified according to endoscopic ultrasonography-determined invasion depth as EUS-M/SM1 (lesions confined to sonographic layers 1 and 2 or lesions with changes in sonographic layer 3; depth, < 1 mm) and EUS-SM2 (lesions with changes in sonographic layer 3; depth, ≥ 1 mm). We evaluated the invasion depth determination accuracy of endoscopic ultrasonography and analyzed the clinicopathological features of misdiagnosed early gastric cancer cases.

RESULTS

The invasion depth determination accuracy was as follows: EUS-M/SM1: pathological T1a/T1b1 early gastric cancer, 97%; EUS-SM2: pathological T1b2 early gastric cancer, 79%. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were 95%, 98%, 69%, 97%, and 79%, respectively. In EUS-M/SM1 early gastric cancer, tumor size of ≥ 15 mm, presence of ulceration, and undifferentiated histological type were significantly associated with endoscopic ultrasonography accuracy. In EUS-SM2 early gastric cancer, tumor size of ≥ 30 mm was significantly associated with endoscopic ultrasonography accuracy.

CONCLUSIONS

Endoscopic ultrasonography is a useful modality in accurately determining the invasion depth of early gastric cancer before endoscopic submucosal dissection.

Nomogram using F-18 fluorodeoxyglucose positron emission tomography/computed tomography for preoperative prediction of lymph node metastasis in gastric cancer

BACKGROUND

Lymph node (LN) metastasis is an important prognostic factor in patients with gastric cancer (GC). However, the evaluation of LN metastasis status in the preoperative setting is not accurate. Therefore, precise preoperative prediction of LN metastasis status is crucial for optimal treatment in patients with GC.

AIM

To develop a preoperative nomogram for LN metastasis using F-18 fluorodeoxyglucose (F-18 FDG) positron emission tomography/computed tomography (PET/CT) and preoperative laboratory test findings in GC.

METHODS

In this study, the data of 566 GC patients who underwent preoperative F-18 FDG PET/CT and subsequent surgical resection were analyzed. The LN metastasis prediction model was developed in the training cohort and validated in the internal validation cohort. Routine preoperative laboratory tests, including albumin and carbohydrate antigen (CA) 19-9 were performed in all patients. Univariate and multivariable logistic regression was performed to validate the preoperative predictive indicators for LN metastasis.

RESULTS

Of the 566 patients, 232 (41%) had confirmed histopathologic LN metastasis. Univariate logistic regression revealed that the tumor location, blood hemoglobin, serum albumin levels, neutrophil to lymphocyte ratio, platelet to lymphocyte ratio, CA 19-9, maximum standardized uptake value (SUVmax) of the primary tumor (T_SUVmax), and SUVmax of LN (N_SUVmax) were significantly associated with LN metastasis. In multivariate analysis, T_SUVmax (OR = 1.08; 95%CI: 1.02–1.15; P = 0.011) and N_SUVmax (OR = 1.49; 95%CI: 1.19–1.97; P = 0.002) were found to be significant predictive factors for LN metastasis. The LN metastasis prediction model using T_SUVmax, N_SUVmax, serum albumin, and CA 19-9 yielded an area under the curve (AUC) of 0.733 (95%CI: 0.683–0.784, P = 0.025) in the training cohort and AUC of 0.756 (95%CI: 0.678–0.833, P < 0.001) in the test cohort.

CONCLUSION

T_SUVmax and N_SUVmax measured by preoperative F-18 FDG PET/CT are independent predictive factors for LN metastasis in GC.

Endoscopic ultrasonography for pretreatment T-staging of gastric cancer: An in vitro accuracy and discrepancy analysis

In the current era of multi-disciplinary treatment, precise and detailed diagnosis prior to treatment is crucial for clinical practice. For different lesions that fit different indications, the optimum approach for treatment differs significantly. Thus, the recent 8th American Joint Committee on Cancer classification system has introduced 'clinical stage' as a criterion. Endoscopic ultrasonography (EUS) has been the first-line choice for pretreatment staging; however, there is no standardization of the depth classification nor a standard EUS method. Additionally, the accuracy for this diagnostic test has ranged between <40 and 90% in previous studies. The aim of the present study was to determine the accuracy of EUS, identify the discrepancies between EUS and histological results, and analyze the underlying causes. Between June 2014 and February 2016, EUS was performed on gastric carcinoma specimens from 60 consecutive patients. EUS was performed on the resected specimens following surgery, but prior to fixation in formalin, invasion of the gastric wall was determined and the deepest location was marked with sutures. The ultrasound images were independently interpreted, and the quality of the images was scored by two endoscopists. Subsequently, the ultrasound images were compared with the pathological results of the same section. The overall accuracy of EUS was 75%. For locally advanced gastric cancers, EUS had a relatively high accuracy (33/43, 86%). The EUS results corresponded well with the pathological hematoxylin and eosin staining results, and the deepest points determined by EUS were confirmed by pathology in the majority of cases (85%). In total, 50 and 10 cases were scored as having high/moderate and low quality, associated with accuracies of 86% (43/50) and 20% (2/10), respectively. EUS is valuable for pretreatment T-staging, particularly for advanced cases. Proximal stomach cancer exhibited a tendency for improved accuracy. Overall, the results of the present study suggest that standardized scanning processes, particularly including all-encompassing scanning, proper probe-placement and high image quality, lead to improved accuracy of EUS.

Present status and perspectives of endosonography 2017 in gastroenterology

Endoscopic ultrasound has become an essential tool in modern gastroenterology and abdominal surgery. Compared with all other endoscopic methods, it has the most potential for innovation and its future looks bright. Thus, we compiled this summary of established and novel applications of endoscopic ultrasound methods to inform the reader about what is already possible and where future developments will lead in improving patient care further. This review is structured in four parts. The first section reports on developments in diagnostic endoscopic ultrasound, the second looks at semi-invasive endoscopic ultrasound, and the third discusses advances in therapeutic endoscopic ultrasound. An overview on the future prospects of endoscopic ultrasound methods concludes this article.

Sequential endoscopic ultrasound identifies predictive variables for relapse-free follow-up after neoadjuvant chemotherapy in gastric cancer

BACKGROUND

The accuracy of endosonographic tumor staging after neoadjuvant therapy is less reliable than in primary staging. Therefore, the value of sequential endosonographic examinations after neaodjuvant chemotherapy in gastro-esophageal cancer is discussed controversially. Previous data suggest, that endoscopic ultrasound (EUS) after neoadjuvant treatment using other variables than classic uTN-criteria may identify patients with a better prognosis.

METHODS

In 67 patients with locally advanced gastric cancer treated in curative intent, we performed EUS before and after neoadjuvant chemotherapy. Endosonographic yTN-stage was compared to pathohistological yTN-stage after curative resection. The uTN-stage, yuTN-stage, maximal tumor thickness and maximal lymph node diameter as well as the shift of these variables after neoadjuvant therapy were analyzed for their usefulness to predict recurrence-free follow-up.

RESULTS

Accuracy of EUS for yTN-staging after neoadjuvant therapy was poor, especially in lower tumor stages. However, three heavily correlated variables analyzed by sequential EUS could be used for the prediction of prognosis: low endosonographic tumor stage (yuT0-2) after neoadjuvant chemotherapy, a decrease of two or more steps in uT-stage and a maximal tumor thickness of <15 mm after chemotherapy were significantly associated with recurrence-free follow-up. Endosonographic T-stage before neoadjuvant therapy, as well as lymph node variables before or after chemotherapy, were of no predictive value.

CONCLUSION

In spite of poor concordance between endosonographic and pathohistological TN-stage after neoadjuvant treatment, sequential EUS, performed before and after neoadjuvant therapy, possibly identify patients at risk for tumor relapse after multimodal treatment in gastric cancer. This finding should be validated in a larger patient cohort.

Endoscopic Ultrasound as a Pretreatment Clinical Staging Tool for Gastric Cancer: Association with Pathology and Outcome

BACKGROUND

Endoscopic ultrasound (EUS) is a guideline-recommended diagnostic test to estimate pretreatment clinical stage in gastric cancer. The impact of EUS to discriminate long-term outcomes has not been established.

OBJECTIVES

The objectives of our study were to (1) evaluate the association between EUS and pathologic stage; (2) evaluate the ability of EUS to predict disease-specific survival (DSS); and (3) determine how neoadjuvant chemotherapy (NCT) affects these relationships.

METHODS

A prospective gastric cancer database at a tertiary care cancer center identified 734 patients who underwent curative intent resection. Patients were separated into EUS low-risk (T1-2, N0) and EUS high-risk (T3-4 Nany, or Tany N+) groups. Agreement statistics and 5-year DSS were estimated stratified by NCT.

RESULTS

Between 1987 and 2015, 68% (502/734) of patients were not treated with NCT. Among these patients, percentage agreement between EUS and pathology was moderate (individual T stage: 52%; N stage: 70%; risk group: 73%). EUS accurately estimated pathologic risk group in 73% (365/502) of patients, whereas it overestimated pathologic risk group in 19% (93/502) of patients and underestimated risk in 8% (41/502) of patients. EUS in non-NCT staging was able to discriminate DSS for T stage (hazard ratio [HR] 5.07, p < 0.05), N stage (HR 3.58, p < 0.05), and risk group (HR 6.35, p < 0.05). Among patients treated with NCT, EUS was unable to discriminate DSS for T stage (HR 0.94, p > 0.05), N stage (HR 1.46, p > 0.05) and risk group (HR 0.50, p > 0.05).

CONCLUSIONS

Pretreatment clinical staging based on EUS alone could lead to over- or under treatment in 27% of patients and can discriminate DSS in NCT-naive patients. EUS should be used in the context of other validated clinical risk tools.

Diffusion-weighted whole-body imaging with background body signal suppression/T2 image fusion and positron emission tomography/computed tomography of upper gastrointestinal cancers

PURPOSE

Diffusion-weighted whole-body imaging with background body signal suppression/T2 image fusion (DWIBS/T2) strongly contrasts cancerous tissue against background healthy tissues. Positron emission tomography/computed tomography (PET/CT) applies the uptake of 18-fluorodeoxyglucose in the diagnosis of cancer. Our aim was to compare DWIBS/T2 and PET/CT in patients with upper gastrointestinal cancers.

METHODS

Patient records, including imaging results from July 2012 to March 2015, were analyzed retrospectively. Four men (age, 72.5 ± 5.3 years) and ten women (age, 71.6 ± 4.0 years) were enrolled in this study. The numbers of patients with esophageal cancer, gastric cancer, gastrointestinal stromal tumor, and duodenal cancer were one, eight, three, and two, respectively.

RESULTS

Six out of eight patients with gastric cancer had positive results on both DWIBS/T2 and PET/CT. The diameter and depth of invasion of gastric cancer was larger in patients with positive DWIBS/T2 and PET/CT findings than those with negative findings. These results suggested that patients with gastric cancer with larger pixel numbers might tend to show positive results with DWIBS/T2.

CONCLUSIONS

DWIBS/T2 and PET/CT have similar sensitivity for the diagnosis of upper gastrointestinal cancer. The diameter and depth of invasion affected the detectability of gastric cancer.

Staging laparoscopy improves treatment decision-making for advanced gastric cancer

AIM: To evaluate the clinical value of staging laparoscopy in treatment decision-making for advanced gastric cancer (GC).

METHODS: Clinical data of 582 patients with advanced GC were retrospectively analyzed. All patients underwent staging laparoscopy. The strength of agreement between computed tomography (CT) stage, endoscopic ultrasound (EUS) stage, laparoscopic stage, and final stage were determined by weighted Kappa statistic (Kw). The number of patients with treatment decision-changes was counted. A χ² test was used to analyze the correlation between peritoneal metastasis or positive cytology and clinical characteristics.

RESULTS: Among the 582 patients, the distributions of pathological T classifications were T2/3 (153, 26.3%), T4a (262, 45.0%), and T4b (167, 28.7%). Treatment plans for 211 (36.3%) patients were changed after staging laparoscopy was performed. Two (10.5%) of 19 patients in M1 regained the opportunity for potential radical resection by staging laparoscopy. Unnecessary laparotomy was avoided in 71 (12.2%) patients. The strength of agreement between preoperative T stage and final T stage was in almost perfect agreement (Kw = 0.838; 95% confidence interval (CI): 0.803-0.872; P < 0.05) for staging laparoscopy; compared with CT and EUS, which was in fair agreement. The strength of agreement between preoperative M stage and final M stage was in almost perfect agreement (Kw = 0.990; 95% CI: 0.977-1.000; P < 0.05) for staging laparoscopy; compared with CT, which was in slight agreement. Multivariate analysis revealed that tumor size (≥ 40 mm), depth of tumor invasion (T4b), and Borrmann type (III or IV) were significantly correlated with either peritoneal metastasis or positive cytology. The best performance in diagnosing P-positive was obtained when two or three risk factors existed.

CONCLUSION: Staging laparoscopy can improve treatment decision-making for advanced GC and decrease unnecessary exploratory laparotomy.

Accuracy of endoscopic ultrasonography for determination of tumor invasion depth in gastric cancer

BACKGROUND

Gastric cancer (GC) is one the common lethal cancers in Iran. Detection of GC in the early stages would assesses to improve the survival of patients. In this study, we attempt to evaluate the accuracy of EUS in detection depth of invasion of GC among Iranian Patients.

MATERIALS AND METHODS

This study is a retrospective study of patients with pathologically confirmed GC. They underwent EUS before initiating the treatment. The accuracy of EUS and agreement between the two methods was evaluated by comparing pre treatment EUS finding with post operative histopathological results.

RESULTS

The overall accuracy of EUS for T and N staging was 67.9% and 75.47, respectively. Underestimation and overestimation was seen in 22 (14.2%) and 40 (25.6%) respectively. The EUS was more accurate in large tumors and the tumors located in the middle and lower parts of the stomach. The EUS was more sensitive in T3 staging. The values of weighted Kappa from the T and N staging were 0.53 and 0.66, respectively.

CONCLUSIONS

EUS is a useful modality for evaluating the depth of invasion of GC. The accuracy of EUS was higher if the tumor was located in the lower parts of the stomach and the size of the tumor was more than 3 cm. Therefore, judgments made upon other criteria evaluated in this study need to be reconsidered.

Detection of gastric cancer using transabdominal ultrasonography is associated with tumor diameter and depth of invasion

Gastric cancer is occasionally diagnosed using transabdominal ultrasonography (US) during screening or investigation of patients with abdominal symptoms. Therefore, the present study analyzed the association of the tumor diameter, pathological T (pT) staging and depth of invasion with the detection of gastric cancer using US. Patient records were analyzed retrospectively and 13 patients were enrolled, who underwent US screening prior to endoscopic mucosal resection, endoscopic submucosal dissection or surgery. In total, 5 patients were diagnosed with gastric cancer using US (positive detection group), while US was unable to detect the gastric cancer in 8 patients (negative detection group). The tumor diameter and depth of invasion were determined by pathologists. One-way analysis of variance or the χ² test was performed. Wall thickness in gastric cancer cases ranged between 7 and 20 mm (mean, 12.2±5.9 mm), as measured using abdominal US. The hemoglobin level was significantly lower in the positive detection patients compared with the negative detection patients (P=0.0455). In addition, the diameters of the gastric wall in the negative and positive detection patients were 24.5±16.4 and 54.4±26.2 mm, respectively (P=0.0266). These results indicate that gastric cancer in the positive detection patients were at a more advanced-stage compared with that in the negative detection patients. Furthermore, gastric cancer with a stage over pT2 was diagnosed using abdominal US (P=0.0242), whereas stage pT1a gastric cancer was not detected by abdominal US. Gastric tumors invading deeper than the submucosa were diagnosed using US (P=0.0242). However, the gastric cancer cases limited to the mucosa remained undetected. In conclusion, the detection of gastric cancer correlated well with the tumor diameter, pT staging and depth of invasion.

Prognostic Role of a Multimarker Analysis of Circulating Tumor Cells in Advanced Gastric and Gastroesophageal Adenocarcinomas

OBJECTIVE

We aimed to assess the prognostic value of circulating tumor cells (CTC) in patients with advanced gastric and gastroesophageal adenocarcinomas.

METHODS

The presence of CTC was evaluated in 62 patients with advanced gastric and gastroesophageal adenocarcinomas before systemic therapy and at follow-up through immunomagnetic enrichment for mucin 1- and epithelial cell adhesion molecule (EpCAM)-positive cells, followed by real-time RT-PCR of the tumor-associated genes KRT19, MUC1, EPCAM, CEACAM5 and BIRC5.

RESULTS

The patients were stratified into groups according to CTC detection (CTC negative: with all marker genes negative; CTC positive: with at least 1 of the marker genes positive). Patients who were CTC positive at baseline had a significantly shorter median progression-free survival (PFS; 3.5 months, 95% CI: 2.9-4.2) and overall survival (OS; 5.8 months, 95% CI: 4.5-7.0) than patients lacking CTC (PFS 10.7 months, 95% CI: 6.9-14.4, p<0.001; OS 13.3 months, 95% CI: 8.0-18.6, p=0.003). Alterations in the marker profile during the course of chemotherapy were not predictive of clinical outcome or response to therapy. Yet, a favorable clinical response depended significantly on CTC negativity (p=0.03).

CONCLUSION

Our data suggest that the presence of CTC is a major predictor of outcome in patients with gastric and gastroesophageal malignancies.

Accuracy of EUS and CT imaging in preoperative gastric cancer staging

BACKGROUND

Neoadjuvant therapy is recommended for locally advanced gastric cancer patients (stage IB-IIIC). The objective of this study is to evaluate the accuracy of endoscopic ultrasound (EUS) and computed tomography (CT) in identifying patients with locally advanced gastric cancer.

METHODS

Patients with gastric adenocarcinoma who underwent gastrectomy at our institution were reviewed. Preoperative EUS and CT staging were compared with pathologic staging to determine accuracy.

RESULTS

Between 2001 and 2013, 280 patients were identified. Forty-nine patients (18%) who underwent preoperative staging by EUS were analyzed. The accuracy of EUS in identifying individual T stage and N stage was 41.0% and 42.9%, respectively. EUS had moderate accuracy in differentiating locally advanced from early (stage 0-IA) disease (75.5%, area under curve (AUC) 0.772). For individual T stage and N stage, the accuracy of CT was 4.0% and 56%, respectively. CT had relatively poor accuracy in differentiating locally advanced from early disease (60.0%, AUC 0.649).

CONCLUSIONS

EUS and CT had poor performance in identifying individual T and N stage although EUS demonstrated moderate accuracy in identifying patients with locally advanced disease. A combined staging approach, in addition to further optimization of staging modalities, is required for accurate staging for patients with gastric cancer.

Use of endoscopic ultrasound in the preoperative staging of gastric cancer: a multi-institutional study of the US gastric cancer collaborative

BACKGROUND

Endoscopic ultrasound (EUS) can be used to guide the therapeutic plan for patients with gastric adenocarcinoma (GAC), but data on its use and accuracy remain poorly defined. We sought to define the use of EUS, as well as characterize the diagnostic accuracy of EUS among patients with GAC.

STUDY DESIGN

We identified 960 patients who underwent resection of GAC between 2000 and 2012 from 7 major academic institutions participating in the US Gastric Cancer Collaborative. Clinicopathologic and EUS data were collected and analyzed using chi and kappa statistics.

RESULTS

Of 960 patients, 223 (23.2%) underwent evaluation with preoperative EUS. Among patients who underwent EUS, 74 (33.2%) received neoadjuvant chemotherapy; 149 (66.8%) proceeded directly to resection. Among patients who did not receive neoadjuvant therapy and received curative intent gastric resection, the EUS T classifications were T1 (33.3%), T2 (35.6%), T3 (18.9%), T4 (12.1%) and the N classifications were N0 (68.1%) and N ≥ 1 (31.9%). In contrast, when tumor stage was based on the final surgical specimen, there was a higher proportion of cases with more advanced T stage (T1, 36.4%; T2, 14.4%; T3, 23.5%; T4, 25.7%) and N stage (N0, 51.3%; N ≥ 1, 48.7%). The agreement of preoperative EUS compared with surgical staging for T (kappa = 0.28, p < 0.001) and N (kappa = 0.33, p < 0.001) classification was only fair.

CONCLUSIONS

Less than one-quarter of patients with GAC underwent preoperative EUS staging. In patients who did not receive preoperative chemotherapy, tumor stage on EUS often did not correlate with T stage and N stage on final pathologic analysis. Endoscopic ultrasound should be combined with other staging modalities to optimize staging of patients with GAC.