Endoscopic ultrasonography in patients with gastro-esophageal cancer

Role of Endoscopic Mucosal Resection and Endoscopic Submucosal Dissection in the Management of Barrett's Related Neoplasia

Endoscopic resection has been proven to be safe and highly effective for removing early neoplastic lesions in Barrett esophagus. It enables accurate histopathological assessment and is therefore considered as the cornerstone in the endoscopic work-up for patients with Barrett neoplasia. Various techniques are available to perform endoscopic resection. Multiband mucosectomy is the most commonly used resection technique. However, endoscopic submucosal dissection is gaining ground in the Western world. Endoscopic resection for low-risk submucosal lesions already is fully justified. Future studies have to point out whether endoscopic resection and subsequent follow-up are also justified in selected patients with high-risk submucosal tumors.

Gastric carcinoma: imaging diagnosis, staging and assessment of treatment response

Gastric carcinoma (GC) is one of the most common causes of cancer-related death worldwide. Surgical resection is the only cure available and is dependent on the GC stage at presentation, which incorporates depth of tumor invasion, extent of lymph node and distant metastases. Accurate preoperative staging is therefore essential for optimal surgical management with consideration of preoperative and/or postoperative chemotherapy. Multidetector computed tomography (MDCT) with its ability to assess tumor depth, nodal disease and metastases is the preferred technique for staging GC. Endoscopic ultrasonography is more accurate for assessing the depth of wall invasion in early cancer, but is limited in the assessment of advanced local or stenotic cancer and detection of distant metastases. Magnetic resonance imaging (MRI), although useful for staging, is not proven to be effective. Positron emission tomography (PET) is most useful for detecting and characterizing distant metastases. Both MDCT and PET are useful for assessment of treatment response following preoperative chemotherapy and for detection of recurrence after surgical resection. This review article discusses the usefulness of imaging modalities for detecting, staging and assessing treatment response for GC and the potential role of newer applications including CT volumetry, virtual gastroscopy and perfusion CT in the management of GC.

Preoperative assessment of tumor location and station-specific lymph node status in patients with adenocarcinoma of the gastroesophageal junction

BACKGROUND

In esophageal cancer patients preoperative staging will determine the type of surgical procedure and use of neoadjuvant therapy. Tumor location and lymph node status play a pivotal role in this tailored strategy. The aim of the present study was to prospectively evaluate the accuracy of preoperative assessment of tumor location according to the Siewert classification and lymph node status per station with endoscopy/endoscopic ultrasound (EUS) and computed tomography (CT).

METHODS

In 50 esophagectomy patients with adenocarcinoma of the gastroesophageal junction (GEJ), tumor location according to Siewert and N-stage per nodal station as determined preoperatively by endoscopy/EUS and CT were compared with the histopathologic findings in the resection specimen.

RESULTS

Overall accuracy in predicting tumor location according to the Siewert classification was 70 % for endoscopy/EUS and 72 % for CT. Preoperative data could not be compared with the pathologic assessment in 11 patients (22 %), as large tumors obscured the landmark of the gastric folds. The overall accuracy for predicting the N-stage in 250 lymph node stations was 66 % for EUS and 68 % for CT. The accuracy was good for those stations located high in the thorax, but poor for celiac trunk nodes.

CONCLUSIONS

Given the frequent discrepancy between the endoscopic and pathologic location of the GEJ and the common problem of advanced tumors obscuring the landmarks used in the assessment of the Siewert classification, its usefulness is limited. The overall accuracy for EUS and CT in predicting the N-stage per station was moderate.

Endoscopic Therapy of Neoplasia Related to Barrett's Esophagus and Endoscopic Palliation of Esophageal Cancer

Background

Barrett's esophagus (BE) is the most important identifiable risk factor for the progression to esophageal adenocarcinoma.

Methods

This article reviews the current endoscopic therapies for BE with high-grade dysplasia and intramucosal cancer and briefly discusses the endoscopic palliation of advanced esophageal cancer.

Results

The diagnosis of low-grade or high-grade dysplasia (HGD) is based on several cytologic criteria that suggest neoplastic transformation of the columnar epithelium. HGD and carcinoma in situ are regarded as equivalent. The presence of dysplasia, particularly HGD, is also a risk factor for synchronous and metachronous adenocarcinoma. Dysplasia is a marker of adenocarcinoma and also has been shown to be the preinvasive lesion. Esophagectomy has been the conventional treatment for T1 esophageal cancer and, although debated, is an appropriate option in some patients with HGD due to the presence of occult cancer in over one-third of patients.

Conclusions

Endoscopic ablative modalities (eg, photodynamic therapy and cryoablation) and endoscopic resection techniques (eg, endoscopic mucosal resection) have demonstrated promising results. The significant morbidity and mortality of esophagectomy makes endoscopic treatment an attractive potential option.

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.

How useful is preoperative imaging for tumor, node, metastasis (TNM) staging of gastric cancer? A meta-analysis

BACKGROUND

Surgery is the fundamental curative option for gastric cancer patients. Imaging scans are routinely prescribed in an attempt to stage the disease prior to surgery. Consequently, the correlation between radiology exams and pathology is crucial for appropriate treatment planning.

METHODS

Systematic searches were conducted using Medline, Embase, and the Cochrane Central Register of Controlled Trials from January 1, 1998 to December 1, 2009. We calculated the accuracy, overstaging rate, understaging rate, Kappa statistic, sensitivity, and specificity for abdominal ultrasound (AUS), computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET) with respect to the gold standard (pathology). We also compared the performance of CT by detector number and image type. A meta-analysis was performed.

RESULTS

For pre-operative T staging MRI scans had better performance accuracy than CT and AUS; CT scanners using ≥ 4 detectors and multi-planar reformatted (MPR) images had higher staging performances than scanners with <4 detectors and axial images only. For pre-operative N staging PET had the lowest sensitivity, but the highest specificity among modalities; CT performance did not significantly differ by detector number or addition of MPR images. For pre-operative M staging performance did not significantly differ by modality, detector number, or MPR images.

CONCLUSIONS

The agreement between pre-operative TNM staging by imaging scans and post-operative staging by pathology is not perfect and may affect treatment decisions. Operator dependence and heterogeneity of data may account for the variations in staging performance. Physicians should consider this discrepancy when creating their treatment plans.

Pattern of lymph node metastases and its implication in radiotherapeutic clinical target volume in patients with thoracic esophageal squamous cell carcinoma: A report of 1077 cases

PURPOSE

To study the pattern of lymph node metastases after esophagectomy and clarify the clinical target volume (CTV) delineation of thoracic esophageal squamous cell carcinoma (ESCC).

METHODS AND MATERIALS

Total 1077 thoracic ESCC patients who had undergone esophagectomy and lymphadenectomy were retrospectively examined. The clinicopathologic factors related to lymph node metastasis were analyzed using logistic regression analysis.

RESULTS

The rates of lymph node metastases in patients with upper thoracic tumors were 16.7% (9/54) cervical, 38.9% (18/54) upper mediastinal, 11.1% (6/54) middle mediastinal, 5.6% (3/54) lower mediastinal, and 5.6% (3/54) abdominal, respectively. The rates of lymph node metastases in patients with middle thoracic tumors were 4.0% (27/680), 3.8% (26/680), 32.9% (224/680), 7.1% (48/680), and 17.1% (116/680), respectively. The rates of lymph node metastases in patients with lower thoracic tumors were 1.0% (5/343), 3.0% (10/343), 22.7% (78/343), 37.0% (127/343), and 33.2% (114/343), respectively. T stage, the length of tumor and the histological differentiation emerged as statistically significant risk factors of lymph node metastases of thoracic ESCC (P < 0.001).

CONCLUSIONS

T stage, the length of tumor and the histologic differentiation influence the pattern of lymph node metastases in thoracic ESCC. These factors should be considered comprehensively to design the CTV for radiotherapy (RT) of thoracic ESCC. Selective regional irradiation including the correlated lymphatic drainage regions should be performed as well.

Endoscopic therapy using radiofrequency ablation for esophageal dysplasia and carcinoma in Barrett's esophagus

Radiofrequency ablation (RFA) is a novel and promising treatment modality for treatment of Barrett's esophagus (BE) with high-grade dysplasia or early carcinoma. RFA can be used as a single-modality therapy for flat-type mucosa or as a supplementary therapy after endoscopic resection of visible abnormalities. The treatment protocol consists of initial circumferential ablation using a balloon-based electrode, followed by focal ablation of residual Barrett's epithelium. RFA is less frequently associated with stenosis and buried glandular mucosa as are other ablation techniques and has shown to be safe and effective in the treatment of patients with BE and early neoplasia. In this article, the technical background, current clinical experience, and future prospects of RFA are evaluated.

Imaging in local staging of gastric cancer: a systematic review

PURPOSE

Endoscopic ultrasound (EUS) has been established as the diagnostic modality of choice in local (T) staging of gastric cancer. Multidetector row computed tomography (MDCT) and magnetic resonance imaging (MRI) are promising alternatives. The aim of this study was to systematically review the literature regarding the performance of each of these imaging modalities.

METHODS

A systematic search for relevant studies was performed in the PubMed/MEDLINE and EMBASE databases. Two reviewers independently assessed the methodological quality of each study. Local staging performance of included studies was calculated.

RESULTS

Twenty-two EUS studies, five MDCT studies, one combined EUS and MDCT study, and three MRI studies met the inclusion criteria. The studies were of moderate methodological quality. Diagnostic accuracy of overall T staging for EUS, MDCT, and MRI varied between 65% to 92.1%, 77.1% to 88.9%, and 71.4% to 82.6%, respectively. Sensitivity for assessing serosal involvement for EUS, MDCT, and MRI varied between 77.8% to 100%, 82.8% to 100%, and 89.5% to 93.1%, respectively. Specificity for assessing serosal involvement for EUS, MDCT, and MRI varied between 67.9% to 100%, 80% to 96.8%, and 91.4% to 100%, respectively.

CONCLUSION

EUS, MDCT, and MRI achieve similar results in terms of diagnostic accuracy in T staging and in assessing serosal involvement. Most experience has been gained with EUS. Few MDCT studies and even fewer MRI studies are available. Thus, EUS remains the first-choice imaging modality in preoperative T staging of gastric cancer.

The endoscopic diagnosis and staging of oesophageal adenocarcinoma

The endoscopic evaluation of patients with oesophageal adenocarcinoma does not only serve the purpose of diagnosing the lesion and obtaining biopsies for histological evaluation: a systematic description of advanced lesions is also required to guide further therapeutic decisions. New endoscopic imaging modalities hold the promise of better endoscopic detection of early cancer and its precursor lesions in Barrett's oesophagus. Video-autofluorescence and narrow band imaging are the most promising techniques in this respect. The former may be used as a 'red flag' technique, identifying lesions that remain occult with white light endoscopy; the latter may be used as a targeted imaging technique, allowing for detailed inspection of the mucosal and vascular patterns that may help to distinguish early neoplasia from non-dysplastic tissue. Currently, prototypes are under investigation that combine high-resolution endoscopy, narrow band imaging and video-autofluorescence in one endoscopy system. Endoscopic ultrasonography (EUS) is superior to any other imaging modality in the assessment of local tumour infiltration of oesophageal adenocarcinoma and locoregional lymph nodes status. EUS allows for the identification of patients with advanced disease who are unlikely to benefit from attempts at curative surgery and in whom a conservative palliative treatment is indicated. EUS may also play a role in the selection of patients for local endoscopic treatment of early oesophageal cancer. EUS guided fine needle aspiration (EUS-FNA) of locoregional lymph nodes is safe with a high sensitivity and an impeccable specificity for assessment of malignant involvement. The indications for EUS-FNA of lymph nodes, however, depend on local treatment protocols: caeliac nodes (M1a) and lymph nodes located at or above the subcarinal area are the most widely used indications. In addition, it may be important if the choice for specific treatment protocols (e.g. neoadjuvant chemoradiotherapy) depends on lymph node status.

Endoscopic treatment of high-grade intraepithelial neoplasia and early cancer in Barrett oesophagus

In the last 5 years, endoscopic therapy for high-grade intraepithelial neoplasia (HGIN) and early cancer (EC) in Barrett oesophagus has emerged as an effective and safe alternative to surgery. Adequate work-up of patients includes histopathological review of the initial biopsies, a high-resolution endoscopy with four-quadrant random biopsies every 1cm of Barrett mucosa and staging with endoscopic ultrasonography. Endoscopic resection (ER) forms the mainstay of the endoscopic treatment since it provides large tissue specimens for optimal histopathological evaluation. The ER-cap technique with submucosal injection and the 'suck-band-and cut' method are the resection methods most widely used in Barrett oesophagus patients. ER monotherapy for HGIN or EC in Barrett oesophagus is associated with recurrent lesions in up to 30% of treated patients. ER may be combined with ablative techniques such as photodynamic therapy (PDT) to treat all of the mucosa at risk for neoplastic progression. Unlike ER, PDT lacks histopathological correlation and residual Barrett mucosa may remain after treatment or may be hidden underneath the neosquamous epithelium. Management of Barrett oesophagus patients with HGIN or EC should be performed in centres with multi-disciplinary experience in this field and future studies should focus on development of ER techniques that allow radical resection of the whole Barrett segment.

Endoscopic complete removal of the histologically unconfirmed gastric cancer with massive invasion as a giant biopsy

A 68-year-old man underwent upper GI endoscopy in a mass screening, which showed a suspicious tumor in the antral region of stomach. However, histologic examination of repeated endoscopic biopsy samples (15 samples) revealed no neoplastic change. Although all the examinations including endoscopy, endosonography, and barium study pointed to the diagnosis of gastric cancer, we did not have histologic evidence of malignancy. Hence, complete endoscopic removal of the lesion using a new method of endoscopic mucosal resection (EMR) was performed as a giant biopsy. Histologic assessment of the endoscopically resected specimen confirmed invasive adenocarcinoma of the stomach. He then underwent distal gastrectomy with regional lymphadenectomy. Endoscopic resection of the tumor in the digestive tract is also a very useful diagnostic modality of the lesion when malignancy cannot be revealed by endoscopic biopsy.

A prospective evaluation of catheter probe EUS for the detection of ascites in patients with gastric carcinoma

BACKGROUND

Gastric carcinoma is known for its propensity to spread to the peritoneum. This study assessed the value of EUS in the detection of ascites not visible on CT in patients with gastric carcinoma.

METHODS

A total of 402 consecutive patients with histopathologically confirmed gastric adenocarcinoma underwent catheter-probe EUS. The accuracy of catheter-probe EUS in the detection of ascites was compared with subsequent findings at laparoscopy or laparotomy.

RESULTS

There was a slight predominance of men in the study population (M:F=1.6:1). Mean patient age was 65.4+/-0.7 years. Ascites was noted by catheter-probe EUS in 36 patients (9.0%). There was no procedure-related morbidity or mortality. Ascites and peritoneal seeding subsequently were found in, respectively, 56 (13.9%) and 66 (16.4%) patients. The finding of ascites by EUS was significantly related to the presence of peritoneal seeding (p<0.001). The sensitivity, specificity, and positive and negative predictive values of EUS in the detection of ascites were, respectively, 60.7%, 99.4%, 94.4%, and 94.0%. The positive and negative likelihood ratios were, respectively, 105.0: 95% CI[26, 425] and 0.40: 95% CI[0.29, 0.55].

CONCLUSIONS

EUS is useful for the detection of ascites in patients with gastric carcinoma.

Endoscopic ultrasonography in preoperative staging of gastric cancer: determination of tumor invasion depth, nodal involvement and surgical resectability

AIM: Current study was aimed to evaluate the usefulness of EUS in TNM staging of gastric cancer by comparing EUS preoperative staging with pathological findings, and the preliminary exploration of possible reasons for overstaging and understaging phenomenon was especially intended.

METHODS: A total of 35 patients with histologically confirmed gastric adenocarcinoma were referred to EUS and staged preoperatively by using the TNM system. The preoperative endosonographic results were compared with the histopathological staging.

RESULTS: The overall accuracy of EUS for determination of the T stage was 80.0%, and for T1, T2, T3, and T4 was 100%, 71.4%, 87.5% and 72.7%, respectively. For N stage, EUS had the accuracy of 68.6%, with sensitivity and specificity of 66.7% and 73.7%, respectively. Resectability was predicted with sensitivity and specificity of 87.5% and 100%, respectively.

CONCLUSION: EUS is an accurate staging modality in most cases, with a few exceptions of overstaging and understaging. Patients with gastric cancers can benefit from preoperative EUS staging for establishing individualized therapy. However, EUS criteria to differentiate benign from malignant nodes still need to be further defined by future studies.

Prognostic value of laparoscopic ultrasound in patients with gastro-esophageal cancer

Forty-four patients with gastro-esophageal tumors regarded as resectable by conventional staging underwent laparoscopic ultrasonography (LUS). Following LUS, seven were found to be irresectable and were managed by palliative therapies. Thirty-seven patients proceeded to surgical exploration and 36 were resected (R0 80%, R1 11%, and R2 9%). All patients were reviewed until death or for a minimum of 24 months. Patients undergoing resection had a 62% 1-year survival (median 17 months; confidence intervals, CI 6-28). LUS defined nodal status indicated a trend toward prolonged survival in the node-negative group, median 22 months (CI 5-39), compared with 13 months (CI 6-20) in the node-positive group. Disease-free survival was greater in LUS node-negative patients at 29 months (CI 23-35) compared with node-positive patients at 13 months (CI 5-21) P=0.0083. LUS staging allows prediction of the likelihood of recurrence of gastro-esophageal malignancies. This may prove useful for the appropriate allocation of patients to primary and adjuvant therapies.