Mohammed A. Kara

Endoscopic video autofluorescence imaging may improve the detection of early neoplasia in patients with Barrett's esophagus.

BACKGROUND The aim of this study was to investigate the feasibility of detecting high-grade dysplasia (HGD) and early cancer (EC) in Barretts esophagus (BE) with a prototype video autofluorescence endoscope. METHODS Sixty patients with BE were evaluated with a prototype, high-resolution videoendoscope that has separate charge-coupled devices for white light endoscopy (WLE) and autofluorescence imaging (AFI). Nondysplastic BE appears green on AFI, whereas potentially neoplastic areas appear blue/violet. The BE was first screened with WLE for visible abnormalities and then was examined by AFI to detect additional lesions. Lesions that raised a suspicion of neoplasia and control areas that were normal on AFI were sampled for histopathologic assessment. Finally, random 4-quadrant biopsy specimens were obtained at 2-cm intervals. RESULTS A diagnosis of HGD/EC was made in 22 patients; one patient had no visible abnormality, and 21 had endoscopically detectable areas with HGD/EC. In 6 of the latter 21 patients, the HGD/EC was detected with AFI alone; in another patient, HGD/EC was detected with AFI and random biopsies. In 14 patients, HGD/EC was detected with both WLE and AFI; in 3 of these 14 patients, additional lesions containing HGD/EC were detected by AFI alone. CONCLUSIONS The results of this study suggest that video AFI may improve the detection of HGD/EC in patients with BE.

Stepwise Radical Endoscopic Resection Is Effective for Complete Removal of Barrett's Esophagus with Early Neoplasia: A Prospective Study

OBJECTIVES:Endoscopic therapy for early neoplasia in Barretts esophagus (BE) is evolving rapidly. Aim of this study was to prospectively evaluate safety and efficacy of stepwise radical endoscopic resection (ER) of BE containing early neoplasia.METHODS:Patients with early neoplasia (i.e., high-grade intraepithelial neoplasia or early cancer) in BE ≤5 cm, without signs of submucosal infiltration or lymph node/distant metastases, were included. Patients underwent resection sessions (cap technique after submucosal lifting) with intervals of 6 wk.RESULTS:Between January 2003 and December 2004, 39 consecutive patients were included. Therapy was discontinued in two patients due to unrelated comorbidity. Complete eradication of early neoplasia was achieved in all 37 treated patients in a median number of three sessions. Complete removal of all Barretts mucosa was achieved in 33 (89%) patients: 4 patients (all had undergone APC [argon plasma coagulation]) were found to have small isles of Barretts mucosa underneath neosquamous mucosa. Complications occurred in two out of 88 (2%) ER procedures: one asymptomatic perforation, one delayed bleeding. Symptomatic stenosis occurred in 10 of 39 (26%) patients and was effectively treated by endoscopic bougienage. During a median follow-up of 11 months, no patients died and none had recurrence of neoplasia or Barretts mucosa.CONCLUSIONS:Stepwise radical ER is effective for selected patients with early neoplasia in BE; provides optimal histopathological diagnosis; and may reduce recurrence rate, since all mucosa at risk is effectively removed. Use of APC should be limited to prevent buried Barretts mucosa. Methods for prevention of stenosis should be developed.

Endoscopic treatment of high-grade dysplasia and early stage cancer in Barrett's esophagus

BACKGROUND The aim of this study was to prospectively evaluate endoscopic resection (ER) combined with photodynamic therapy (PDT) for the treatment of selected patients with early neoplasia in Barretts esophagus. METHODS Patients with Barretts esophagus and neoplastic lesions <2 cm in diameter and no sign of submucosal infiltration, positive lymph nodes, or distant metastasis underwent diagnostic ER (cap technique). Patients with a T1sm tumor in the resection specimen were referred for surgery; those with a T1m or a less invasive tumor underwent additional endoscopic therapy (ER, PDT, and/or argon plasma coagulation [APC]), or they were followed. PDT was performed with 5-aminolevulinic acid and a light dose of 100 J/cm 2 at lambda = 632 nm. RESULTS Thirty-three patients underwent diagnostic ER. Endoscopic treatment was not performed in 5 patients, who underwent surgery (4 T1sm; 1, patient preference). Five patients were immediately entered into a follow-up protocol, and 23 received additional endoscopic treatment (13 additional ER, 19 PDT, 3 APC). Endoscopic treatment was successful in 26/28 patients; no severe complication was observed. During follow-up (median 19 months, range 13-24 months), 5/26 patients had a recurrence of high-grade dysplasia: all were successfully re-treated with ER. At the end of follow-up, 26/33 originally enrolled patients (79%) and 26/28 endoscopically treated patients (93%) were in local remission. CONCLUSIONS Endoscopic therapy is safe and effective for selected patients with early stage neoplasia in Barretts esophagus.

A randomized crossover study comparing light-induced fluorescence endoscopy with standard videoendoscopy for the detection of early neoplasia in Barrett's esophagus

BACKGROUND Light-induced fluorescence endoscopy (LIFE) may improve the detection of high-grade dysplasia (HGD) and early stage cancer (EC) in Barretts esophagus (BE). The aim of this study was to compare LIFE with standard endoscopy (SE) in a randomized crossover study. METHODS Fifty patients with BE underwent SE and LIFE in a randomized sequence (4 to 6-week interval between procedures). The two procedures were performed by two different endoscopists who were blinded to the findings of the other examination. Targeted biopsy specimens were taken from detected lesions, followed by random biopsy specimens with a 2-cm interval, 4-quadrant protocol. Biopsy specimens were routinely evaluated and subsequently reviewed by a single, blinded expert GI pathologist. RESULTS Targeted biopsy specimens had a sensitivity for the diagnosis of HGD/EC of 62% (8/13) for both techniques. The overall sensitivity (all biopsy specimens) was 85% for SE and 69% for LIFE (p = 0.69). All targeted biopsy specimens had a positive predictive value (PPV) for HGD/EC of 41% for SE and 28% for LIFE (p = 0.40); autofluorescence-targeted biopsy specimens had a PPV of 13%. False-positive lesions had a significantly higher rate of acute inflammation than random biopsy specimens. CONCLUSIONS In this study, LIFE did not improve the detection of HGD or EC in patients with BE compared with SE.

Clinical evaluation of endoscopic trimodal imaging for the detection and differentiation of colonic polyps.

BACKGROUND & AIMS Endoscopic trimodal imaging (ETMI) incorporates high-resolution endoscopy (HRE) and autofluorescence imaging (AFI) for adenoma detection, and narrow-band imaging (NBI) for differentiation of adenomas from nonneoplastic polyps. The aim of this study was to compare AFI with HRE for adenoma detection and to assess the diagnostic accuracy of NBI for differentiation of polyps. This was a randomized trial of tandem colonoscopies. The study was performed at the Academic Medical Center in Amsterdam. METHODS One hundred patients underwent colonoscopy with ETMI. Each colonic segment was examined twice for polyps, once with HRE and once with AFI, in random order per patient. All detected polyps were assessed with NBI for pit pattern and with AFI for color, and subsequently removed. Histopathology served as the gold standard for diagnosis. The main outcome measures of this study were adenoma miss-rates of AFI and HRE, and diagnostic accuracy of NBI and AFI for differentiating adenomas from nonneoplastic polyps. RESULTS Among 50 patients examined with AFI first, 32 adenomas were detected initially. Subsequent inspection with HRE identified 8 additional adenomas. Among 50 patients examined with HRE first, 35 adenomas were detected initially. Successive AFI yielded 14 additional adenomas. The adenoma miss-rates of AFI and HRE therefore were 20% and 29%, respectively (P = .351). The sensitivity, specificity, and overall accuracy of NBI for differentiation were 90%, 70%, and 79%, respectively; corresponding figures for AFI were 99%, 35%, and 63%, respectively. CONCLUSIONS The overall adenoma miss-rate was 25%; AFI did not significantly reduce the adenoma miss-rate compared with HRE. Both NBI and AFI had a disappointing diagnostic accuracy for polyp differentiation, although AFI had a high sensitivity.

Multiband mucosectomy for endoscopic resection of Barrett's esophagus : feasibility study with matched historical controls

Background and aims Piece-meal endoscopic resection of early neoplastic lesions larger than 15–20 mm is a laborious procedure with the cap technique. Multiband mucosectomy is a new technique using a modified variceal band ligator. Submucosal lifting and prelooping of the snare in the cap is not necessary and multiple resections can be performed with a single snare. We prospectively evaluated the feasibility of multiband mucosectomy for widespread endoscopic resection in patients with a Barretts esophagus with early neoplasia and compared results retrospectively with prospectively registered endoscopic cap resection procedures. Results Eighty multiband mucosectomy procedures were performed in 40 patients and 86 endoscopic cap resection procedures in 53 patients. Median duration of the multiband mucosectomy procedures was 37 vs. 50 min for endoscopic cap resection procedures (P=0.06); median duration per resection was 6 vs. 12 min, respectively (P<0.001). Mean diameter of the specimens was 17 vs. 21 mm (P<0.001). One perforation in the endoscopic cap resection group was successfully treated conservatively. Mild bleeding occurred in 6% of multiband mucosectomy and 20% of endoscopic cap resection procedures (P=0.012). Technical difficulties during multiband mucosectomy procedures included a decreased visibility owing to the black bands and the releasing wires. Conclusions Multiband mucosectomy allows safe and easy widespread piece-meal resections in Barretts esophagus. Time and costs appear to be saved compared with the cap technique, and multiband mucosectomy appears to cause less bleeding during the endoscopic resection procedure. Multiband mucosectomy, however, results in smaller specimens and is, therefore, most suited for en-bloc resection of lesions smaller than 10 mm or for widespread resection of flat mucosa.

Autofluorescence-Based Detection of Early Neoplasia in Patients with Barrett’s Esophagus

Barrett’s esophagus (BE) is a condition in which the normal stratified squamous lining of the distal esophagus is replaced by metaplastic columnar epithelium. Its importance arises from it being a precancerous condition with the potential to progress to esophageal adenocarcinoma, the incidence of which is dramatically rising in Western countries [1, 2]. Malignant transformation in BE is believed to follow the metaplasia-dysplasia-carcinoma sequence [3], so there is a possibility to detect and treat neoplastic lesions at an early and curable stage. In this article, we will discuss fluorescence-based imaging used adjunctively with conventional endoscopy for the detection of early neoplastic lesions in BE. We will use the term ‘early neoplasia’ to denote lesions with low-grade dysplasia (LGD), high-grade dysplasia (HGD) or early cancer (EC) in BE. Current Surveillance Strategies

Observer agreement in the assessment of narrowband imaging system surface patterns in Barrett’s esophagus: a multicenter study

BACKGROUND AND STUDY AIMS The clinical utility of narrow-band imaging (NBI) for Barretts esophagus is limited by the multiplicity of classification schemes. We evaluated the interobserver agreement and accuracy of a new consensus-driven simplified binary classification of NBI surface patterns.

Effects of Autofluorescence Imaging on Detection and Treatment of Early Neoplasia in Patients With Barrett's Esophagus

BACKGROUND & AIMS Studies have reported that autofluorescence imaging (AFI) increases targeted detection of high-grade intraepithelial neoplasia (HGIN) and intramucosal cancer (IMC) in patients with Barretts esophagus (BE). We analyzed data from trials to assess the clinical relevance of AFI-detected lesions. METHODS We collected information on 371 patients with BE, along with endoscopy and histology findings, from databases of 5 prospective studies of AFI (mean age, 65 years; 305 male). We compared these data with outcomes of treatment and follow-up. Study end points included the diagnostic value of AFI (proportion of surveillance patients with HGIN or IMC detected only by AFI-targeted biopsies) and value of AFI in selection of therapy (the proportion of patients for which detection of an HGIN or IMC lesion by AFI changed the treatment strategy based on white-light endoscopy or random biopsy analysis). RESULTS Of study participants, 211 were referred for surveillance and 160 were referred for early stage neoplasia; HGIN or IMC were diagnosed in 147 patients. In 211 patients undergoing surveillance, 39 had HGIN or IMC (23 detected by white-light endoscopy, 11 detected by random biopsies, 5 detected by AFI). So, the diagnostic value of AFI was 5 (2%) of 211. In 24 patients, HGIN or IMC was diagnosed using only AFI. In 33 patients, AFI detected additional HGINs or IMCs next to lesions detected by primary white-light endoscopy. Lesions detected by AFI were treated in 57 patients: 26 patients underwent radiofrequency ablation and showed full remission of neoplasia, whereas 31 underwent endoscopic resection and 6 were found to have IMC. The value of AFI in selection of therapy was 6 (2%) of 371. CONCLUSIONS Based on an analysis of data from clinical trials of patients with BE, detection of lesions by AFI has little effect on the diagnosis of early stage neoplasia or therapeutic decision making. AFI therefore has a limited role in routine surveillance or management of patients with BE.

Follow-up for high-grade dysplasia in Barrett's esophagus

This article will focus on the value of endoscopic follow-up for patients with high-grade dysplasia (HGD). Because the diagnosis of HGD in Barretts esophagus is not a simple straightforward task, the article first will discuss the controversies regarding the histological diagnosis, followed by a discussion of the importance of endoscopic imaging for making the clinical diagnosis of HGD, and a systematic review of the literature relating to the presence of synchronous cancers in patients with HGD and the occurrence of cancer during endoscopic follow-up in these patients (metachronous cancers). Furthermore, the article will also discuss endoscopic techniques currently available for surveillance of these patients and make recommendations regarding surveillance intervals and the optimal biopsy protocol.