Oliver Pech

Computed Virtual Chromoendoscopy for Classification of Small Colorectal Lesions: A Prospective Comparative Study

OBJECTIVES:Standard colonoscopy offers no reliable discrimination between neoplastic and nonneoplastic colorectal lesions. Computed virtual chromoendoscopy with the Fujinon intelligent color enhancement (FICE) system is a new dyeless imaging technique that enhances mucosal and vascular patterns. This prospective trial compared the feasibility of FICE, standard colonoscopy, and conventional chromoendoscopy with indigo carmine in low- and high-magnification modes for determination of colonic lesion histology.METHODS:Sixty-three patients with 150 flat or sessile lesions less than 20 mm in diameter were enrolled. At colonoscopy, each lesion was observed with six different endoscopic modalities: standard colonoscopy, FICE, and conventional chromoendoscopy with indigo carmine (0.2%) dye spraying in both low- and high-magnification modes. Histopathology of all lesions was confirmed by evaluation of endoscopic resection or biopsy specimens. Endoscopic images were stored electronically and randomly allocated to a blinded reader.RESULTS:Of the 150 polyps, 89 were adenomas and 61 were hyperplastic polyps with an average size of 7 mm. For identifying adenomas, the FICE system with low and high magnifications revealed a sensitivity of 89.9% and 96.6%, specificity of 73.8% and 80.3%, and diagnostic accuracy of 83% and 90%, respectively. Compared with standard colonoscopy, the sensitivity and diagnostic accuracy achieved by FICE were significantly better under both low (P < 0.02) and high (P < 0.03) magnification and were comparable to that of conventional chromoendoscopy.CONCLUSIONS:The FICE system identified morphological details that efficiently predict adenomatous histology. For distinguishing neoplastic from nonneoplastic lesions, FICE was superior to standard colonoscopy and equivalent to conventional chromoendoscopy.

The impact of endoscopic ultrasound and computed tomography on the TNM staging of early cancer in Barrett's esophagus.

INTRODUCTION:Computed tomography (CT) and endoscopic ultrasound (EUS) are part of the regular staging protocol in esophageal cancer. The value of the two methods was assessed in patients with early cancer in Barretts esophagus.METHODS:One hundred consecutive patients (median age 64 yr, interquartile range [IQR] 58–72) with suspected early cancer in Barretts esophagus who were referred to our hospital for endoscopic therapy were prospectively included in a standardized staging program with upper gastrointestinal endoscopy, EUS (7.5 MHz in all cases plus 12.5 or 20 MHz for elevated and/or depressed lesions), CT of the chest and upper abdomen, and abdominal ultrasonography. The results were summarized in accordance with the TNM classification. On the basis of the lymph node findings on CT and/or EUS, the patients were assigned to three categories: C1, no suspicious lymph nodes; C2, paraesophageal lymph nodes ≤1 cm in size at the tumor level, lymph nodes ≥1 cm in size not at the tumor level in the mediastinum or celiac trunk; and C3, paraesophageal lymph nodes >1 cm in size at the tumor level. The EUS and CT findings were checked every 6 months in patients who underwent endoscopic treatment. Surgical resection was scheduled in operable patients if staging showed a T category higher than T1 and/or the lymph node staging was assessed as C3. Patients with suspected submucosal infiltration underwent diagnostic endoscopic resection, and if submucosal involvement was confirmed were referred for surgery.RESULTS:The median follow-up period was 25 months (IQR 19.5–30.0). The T category diagnosed with CT was ≤T1 in all patients. On EUS, the T category was classified as T1 in 92% of cases (N = 92) and as >T1 in 8% (N = 8, p < 0.05). Enlarged lymph nodes (C2 and C3) were detected in 45% of the patients. Significantly more C2 lymph nodes were diagnosed with EUS than CT (28 vs 19, p < 0.05). Lymph nodes at the level with the highest suspicion, C3, were detected using CT in only three of nine cases. Sensitivity of CT for N staging was not acceptable compared with EUS (38% vs 75%). No extranodal metastases were found on CT.CONCLUSIONS:In suspected early cancer in Barretts esophagus, EUS is superior to CT for T staging and N staging. As CT had no influence on the TNM classification in any of these patients, it may be possible to dispense with this method as a staging procedure in patients with cancer in Barretts esophagus. By contrast, EUS is required in order to differentiate between patients with cancer in Barretts esophagus in whom endoscopic therapy is suitable and those in whom surgical treatment is required.

Barrett's esophagus: endoscopic resection.

In experienced hands, ER is a safe method of resecting dysplastic lesions and early carcinomas of the GI tract, and it has decisive advantages compared with other local endoscopic treatment procedures (such as thermal destruction and PDT). The opportunity for histological processing of the resected specimen provides information regarding the depth of invasion of the individual layers of the GI tract wall. Additionally, it has advantages regarding excision with healthy margins. This means that even when there is infiltration of the submucosa that has not been detected before treatment--in which case local endoscopic therapy is no longer appropriate--a patient with early Barretts cancer still is able to undergo surgical resection. As was shown recently, the morbidity and mortality of ER are significantly dependent on the frequency with which esophagectomy is performed in each center. When there were more than 20 procedures of this type per year, the surgical mortality was 8%, whereas in centers conducting fewer than 10 procedures per year the rate was 21%. In view of the consequent claim that ER should only be performed at high-volume centers, curative endoscopic treatment of early esophageal carcinomas also should be performed only in centers with a similar frequency to that of the surgical high-volume centers. It is only in these conditions that the conclusion is defensible that patients with HGIN or mucosal Barretts carcinoma should undergo ER with curative intent instead of radical ER. Randomized and controlled studies comparing radical esophagectomy with endoscopic therapy are desirable, but they are difficult to conduct, not least because valid 5-year survival data show no significant difference between patients who have undergone endoscopic treatment for early Barretts cancers and the average German population of the same age and sex.

Conclusions from the histological diagnosis of low-grade intraepithelial neoplasia in Barrett's oesophagus

Objective. It is well known that low-grade intraepithelial neoplasia (LGIN) in Barretts oesophagus (BE) might progress to high-grade intraepithelial neoplasia (HGIN) or carcinoma. Since accurate diagnosis of LGIN is difficult, general pathologists are frequently uncertain about the diagnosis of LGIN and its follow-up risks. The purpose of this study was to analyse the divergence between the diagnoses of general and specialized gastrointestinal pathologists. Material and methods. Fifty consecutive patients with a previous diagnosis of LGIN in BE, made by a general pathologist, were included in our study. The histopathological slides of every patient were reassessed in a blinded fashion by two specialized gastrointestinal (GI) pathologists. Inter-observer variability was calculated using kappa statistics. Results. LGIN was confirmed by specialized pathologists in only 25/50 patients (50%). Twenty-one patients (42%) had Barretts metaplasia without intraepithelial neoplasia and in 4 patients (8%) HGIN or Barretts carcinoma (BC) was revealed. Inter-observer agreement between the general and specialized pathologists for the diagnosis of LGIN was poor (κ = − 0.17) and good between both of the specialized pathologists (κ = 0.69). Patients with HGIN/BC were treated by endoscopic resection or surgery. In patients with LGIN, ablative therapy was performed. Complete response was achieved in 25 patients, but 3 patients developed HGIN and 1 patient developed BC after 10±3.6 months. Conclusions. BE with LGIN is difficult to diagnose. Inter-observer variability is unacceptable between general and specialized pathologists and therefore when diagnosing LGIN a second opinion should always be sought by a specialized GI pathologist. Ablation therapy seems to be effective in patients with LGIN, but follow-up endoscopies are necessary to detect metachronous neoplasia.

Can EUS elastography improve lymph node staging in esophageal cancer

BackgroundEndoscopic ultrasound (EUS) elastography can assess the hardness of tissue by measuring its elasticity. Few data have been published on EUS elastography for lymph node (LN) staging in patients with esophageal cancer. This study analyzes the value of elastography as an additional diagnostic tool for LN staging.MethodsForty patients (mean age 68xa0years) with known esophageal cancer (34 Barrett’s carcinoma, 6 squamous cell carcinoma) were included prospectively. On conventional EUS, suspicious LNs were assessed using sonomorphologic criteria, and EUS elastography was then used to assess their tissue hardness. The sonomorphologic criteria and elastographic images for the LN were later reviewed on recorded video clips by an endosonographer blinded to the histology results. The proportions of color pixels in LNs in selected patients were assessed using computer analysis of the elastography images. Fine-needle aspiration was performed in all of the LNs, and the histological/cytological results were used as the gold standard.ResultsTwenty-one of the 40 LNs examined (52.5xa0%) were positive for neoplasia, confirmed by histology/cytology. The first assessment by the examiner during the procedure, based on sonomorphologic criteria, showed sensitivity of 91.3xa0% and specificity of 64.7xa0%. EUS elastography alone had sensitivity of 100xa0% and specificity of 64.1xa0%. When computer analysis of the elastographic images was added, the specificity improved significantly to 86.7xa0%, with a slight decrease in sensitivity to 88.9xa0%.ConclusionsEUS elastography is easily included in clinical staging and, particularly with computer-aided pixel analysis, significantly improves the specificity of LN staging.

Management of pre-malignant and malignant lesions by endoscopic resection

Endoscopic resection (ER) has gained more and more importance in the treatment of early gastrointestinal neoplasia over the last few years. The choice of the different available techniques depends on the site, the macroscopic type of the tumour and the personal experience of the endoscopist. The suck-and-cut technique with ligation device or cap should be favoured to normal strip biopsy in the oesophagus because of the size of the resected specimen and its technical feasibility. A recently described method of ER in the stomach is the circumferential mucosal incision with a type of needle-knife and subsequent en-bloc resection following prior injection under the lesions. ER of high-grade intraepithelial neoplasia and mucosal adenocarcinoma in Barretts oesophagus should be considered as the treatment of choice. First mid-term results of endoscopic therapy of early squamous-cell neoplasia in the oesophagus show promising results; however, long-term results are awaited. Studies with large numbers of patients in Japan proved the efficiency and safety of ER in low-risk early gastric carcinoma. Duodenal lesions and adenomas of the major duodenal papilla were also proved to be treated successfully by ER. In the colon, ER is used successfully for resection of adenomas and small well-differentiated or moderately differentiated carcinomas that are restricted to the mucosa. ER of gastrointestinal lesions is a safe and effective method but should be performed only by experienced endoscopists.

Endoscopic Resection of Early Esophageal and Gastric Neoplasias

The advent of endoscopic resection (ER) techniques has enabled gastroenterologists to remove premalignant or neoplastic lesions throughout the gastrointestinal tract. This review discusses the indications and the several techniques of ER in early carcinomas of the esophagus and stomach. Before ER is performed an accurate evaluation of patients and careful staging of lesions is mandatory. After ER of the neoplasia histological assessment of the entire specimen with detailed histological analysis of layer infiltration is crucial. First long-term follow-up studies of large numbers of patients confirm the excellent effectiveness of ER for well-differentiated mucosal lesions without lymphangitic invasions.

Diagnosing early Barrett’s neoplasia and oesophageal squamous cell neoplasia by bioimpedance spectroscopy in human tissue

Background Detection of early oesophageal cancer in surrounding normal tissue can be challenging, but detection is essential to determine the subsequent treatment. Dysplastic tissue can be detected by using electrical impedance spectroscopy (EIS). Objective The aim of the present study was to evaluate the feasibility and value of EIS in the diagnosis of oesophageal neoplasia. Methods This prospective ex-vivo study included 23 patients with early oesophageal cancer (17 with Barrett’s cancer and six with early squamous cell cancer). Immediately after endoscopic resection, the electrical properties of the resected specimens were investigated using a pencil probe (5u2009mm in diameter, frequency range from 100 Hz to 1u2009MHz). Punch biopsies were taken from the measured site in order to compare the results of EIS with histology. Results EIS was able to detect dysplastic oesophageal mucosa with a high rate of accuracy (82% in Barrett’s oesophagus and 100% in squamous oesophagus) A total of 54 different sites in 26 tumours were evaluated. Conclusions EIS was able to differentiate reliably between non-neoplastic and neoplastic oesophageal mucosa. Using EIS, it might be possible to use it for targeted biopsies and to avoid unnecessary biopsies during cancer surveillance in future.

Nonneoplastic and Neoplastic Barrett's Esophagus: The European Perspective

The cancer risk of nondysplastic Barretts esophagus is very low (0.33-0.5 per year). Therefore, any endoscopic ablation technique is an overtreatment. Patients with low-grade intraepithelial neoplasia confirmed by a specialized GI pathologist seem to have a significant risk for developing high-grade intraepithelial neoplasia (HGIN) or cancer. Therefore, endoscopic treatment in this case seems to be justified. However, up to now there has been no prospective study supporting this. In recent years, endoscopic treatment of HGIN and mucosal Barretts cancer has become a widely accepted treatment approach and even the therapy of choice in many countries. Endoscopic resection (ER) is the best validated treatment method in patients with HGIN and mucosal Barretts cancer, and is widely used all over the world. In contrast to ablative treatment methods like argon plasma coagulation and radiofrequency ablation, ER allows histological assessment of the resected specimen in order to assess the depth of infiltration of the tumor. However, ER of the neoplastic lesions should always be followed by ablation of the nondysplastic remaining Barretts esophagus in order to reduce the risk of recurrence or metachronous neoplasia. The long-time complete remission rate with this two-step strategy is ≥95%. A matter of continuing debate is whether patients with Barretts cancer infiltrating the upper third of the mucosal layer (pT1sm1) can be treated by ER. Data from our and other centers indicate that a subgroup of patients with pT1sm1 adenocarcinomas without the presence of risk factors (poor differentiation grade, lymph or blood vessel infiltration, size >20 mm, ulcerated lesion) have a very low risk for lymph node metastasis (<2%) and endoscopic therapy can be an alternative to radical surgery.

Endoscopic Resection for Early Cancers of the Esophagus and Stomach

The advent of endoscopic resection (ER) techniques has enabled gastroenterologists to remove premalignant and early neoplastic lesions throughout the gastrointestinal tract. The indications and techni