Achyut K. Bhattacharyya

Magnification chromoendoscopy for the detection of intestinal metaplasia and dysplasia in Barrett’s oesophagus

Background: The presence of intestinal metaplasia (IM) in the columnar lined distal oesophagus defines Barrett’s oesophagus with the risk of future malignant transformation. The distribution of both IM and dysplasia (low grade (LGD) and high grade (HGD)) within the columnar lined oesophagus is patchy and mosaic requiring random biopsies. Techniques that could help target areas of high yield within Barrett’s mucosa would be helpful. Aim: To study the utility of high magnification chromoendoscopy (MCE) in the detection of IM, LGD, and HGD in patients with Barrett’s oesophagus. Methods: Consecutive patients detected with columnar mucosa in the distal oesophagus were studied using an Olympus magnification endoscope (GIF-Q16OZ, 115×). The distal oesophagus was sprayed with indigo carmine solution and the oesophageal columnar mucosa patterns were noted under high magnification and targeted for biopsy. All biopsies were read by pathologists blinded to the endoscopic findings. Results: Eighty patients with suspected Barrett’s oesophagus (that is, columnar lined distal oesophagus) were studied: mean age 62.7 years (range 35–81). Mean length of columnar mucosa was 3.7 cm (range 0.5–17). Three types of mucosal patterns were noted within the columnar mucosa after spraying indigo carmine and using MCE: ridged/villous pattern, circular pattern, and irregular/distorted pattern. The yield of IM on target biopsies according to the patterns was: ridged/villous 57/62 (97%) and circular 2/12 (17%). Six patients had an irregular/distorted pattern and all had HGD on biopsy (6/6 (100%)). Eighteen patients had LGD on target biopsies; all had the ridged/villous pattern. All patients with long segment Barrett’s were identified using MCE whereas 23/28 patients (82%) with short segment Barrett’s had the ridged/villous pattern. Conclusions: MCE helps visually identify areas with IM and HGD having specific patterns but not patients with LGD (appear similar to IM). MCE may be a useful clinical tool for the increased detection of patients with IM as well as for surveillance of patients for the detection of HGD. If these preliminary results are validated, MCE would help identify high yield areas, potentially eliminating the need for random biopsies.

Proton pump inhibitors are associated with reduced incidence of dysplasia in Barrett's esophagus.

BACKGROUND AND AIMS:Esophageal acid exposure is important in the pathogenesis of Barretts esophagus (BE), and possibly in the progression of BE to dysplasia and carcinoma. The aim of this study is to compare the development of dysplasia in BE patients treated with or without proton pump inhibitor (PPI) or histamine 2-receptor antagonist (H2RA).METHODS:We analyzed prospectively collected data by a single endoscopist on patients with BE in a VA (Veterans Affairs) setting over a 20-yr time period (1981–2000). A pathologist used standard criteria to diagnose BE/dysplasia. Pharmacy information after 1994 was retrieved from a computerized database, and from research files for the period before that. The receipt and the duration of H2RA and/or PPI use was compared between those with and without dysplasia. The incidence of dysplasia was examined in a Kaplan–Meier survival analysis stratified by PPI treatment status, and the risk of dysplasia was examined in a Cox multiple regression analysis controlling for demographic features, length of BE, and the year of BE diagnosis.RESULTS:We analyzed data for 236 unique veteran patients with a mean age at BE diagnosis of 61.5 yr, 86% Caucasian, and 98% male. During 1,170 patient-yr of follow-up, 56 patients developed dysplasia giving an annual incidence rate of 4.7%. Of those, 14 had high-grade dysplasia. The cumulative incidence of dysplasia was significantly lower among patients who received PPI after BE diagnosis than in those who received no therapy or H2RA; log rank test (p < 0.001). Furthermore, among those on PPIs, a longer duration of use was associated with less frequent occurrence of dysplasia. In multivariate analysis, the use of PPI after BE diagnosis was independently associated with reduced risk of dysplasia, hazards ratio: 0.25 (95% CI 0.13–0.47), p < 0.0001. Longer segments of BE and Caucasian race were other independent risk factors for developing dysplasia. In general, similar findings were observed when only cases with high-grade dysplasia were analyzed.CONCLUSIONS:These results indicate that PPI therapy is associated with a significant reduction in the risk of developing dysplasia in patients with BE. However, more studies are required to confirm this finding.

Overview of telepathology, virtual microscopy, and whole slide imaging: prospects for the future ☆

Telepathology, the practice of pathology at a long distance, has advanced continuously since 1986. Today, fourth-generation telepathology systems, so-called virtual slide telepathology systems, are being used for education applications. Both conventional and innovative surgical pathology diagnostic services are being designed and implemented as well. The technology has been commercialized by more than 30 companies in Asia, the United States, and Europe. Early adopters of telepathology have been laboratories with special challenges in providing anatomic pathology services, ranging from the need to provide anatomic pathology services at great distances to the use of the technology to increase efficiency of services between hospitals less than a mile apart. As to what often happens in medicine, early adopters of new technologies are professionals who create model programs that are successful and then stimulate the creation of infrastructure (ie, reimbursement, telecommunications, information technologies, and so on) that forms the platforms for entry of later, mainstream, adopters. The trend at medical schools, in the United States, is to go entirely digital for their pathology courses, discarding their student light microscopes, and building virtual slide laboratories. This may create a generation of pathology trainees who prefer digital pathology imaging over the traditional hands-on light microscopy. The creation of standards for virtual slide telepathology is early in its development but accelerating. The field of telepathology has now reached a tipping point at which major corporations now investing in the technology will insist that standards be created for pathology digital imaging as a value added business proposition. A key to success in teleradiology, already a growth industry, has been the implementation of standards for digital radiology imaging. Telepathology is already the enabling technology for new, innovative laboratory services. Examples include STAT QA surgical pathology second opinions at a distance and a telehealth-enabled rapid breast care service. The innovative bundling of telemammography, telepathology, and teleoncology services may represent a new paradigm in breast care that helps address the serious issue of fragmentation of breast cancer care in the United States and elsewhere. Legal and regulatory issues in telepathology are being addressed and are regarded as a potential catalyst for the next wave of telepathology advances, applications, and implementations.

Increased expression of thioredoxin-1 in human colorectal cancer is associated with decreased patient survival

Thioredoxin-1 is a redox protein that, when overexpressed, causes increased cancer-cell growth and inhibited apoptosis. Thioredoxin-1 expression has been reported to be increased in several human primary tumors, but its relationship to tumor progression and patient survival has not been established. We studied the expression of thioredoxin-1 as measured with immunohistochemical staining in paraffin-embedded human normal colonic mucosa, adenomatous polyps, and primary and metastatic colorectal cancer. Thioredoxin-1 expression was not increased in 12 colorectal adenomatous polyps, compared with 8 samples of normal colonic mucosa, but was significantly increased in 12 primary colorectal cancers (P <.01). Thioredoxin-1 expression was not significantly different in primary lymph-node metastases and the primary colorectal cancer. Using colorectal cancer samples from 37 subjects for whom survival data was available, we found that thioredoxin-1 expression increased with Dukes stage, although the association was not statistically significant (P =.077). We noted a significant association between thioredoxin-1 expression and patient survival (P =.004); higher score was associated with decreased survival. When adjusted for Dukes stage, thioredoxin-1 expression showed a statistically significant association with survival (P =.012). The work shows that increased thioredoxin-1 expression is a relatively late event in colorectal carcinogenesis and provides evidence in a small group of subjects with colorectal cancer of Dukes stages A through D that thioredoxin-1 expression may be an independent marker of patient prognosis.

A multicenter, double-blinded validation study of methylation biomarkers for progression prediction in Barrett’s esophagus

Esophageal adenocarcinoma risk in Barretts esophagus (BE) is increased 30- to 125-fold versus the general population. Among all BE patients, however, neoplastic progression occurs only once per 200 patient-years. Molecular biomarkers are therefore needed to risk-stratify patients for more efficient surveillance endoscopy and to improve the early detection of progression. We therefore performed a retrospective, multicenter, double-blinded validation study of eight BE progression prediction methylation biomarkers. Progression or nonprogression were determined at 2 years (tier 1) and 4 years (tier 2). Methylation was assayed in 145 nonprogressors and 50 progressors using real-time quantitative methylation-specific PCR. Progressors were significantly older than nonprogressors (70.6 versus 62.5 years; P < 0.001). We evaluated a linear combination of the eight markers, using coefficients from a multivariate logistic regression analysis. Areas under the ROC curve (AUC) were high in the 2-year, 4-year, and combined data models (0.843, 0.829, and 0.840; P < 0.001, <0.001, and <0.001, respectively). In addition, even after rigorous overfitting correction, the incremental AUCs contributed by panels based on the 8 markers plus age versus age alone were substantial (Delta-AUC = 0.152, 0.114, and 0.118, respectively) in all 3 models. A methylation biomarker-based panel to predict neoplastic progression in BE has potential clinical value in improving both the efficiency of surveillance endoscopy and the early detection of neoplasia.

Medication Usage and the Risk of Neoplasia in Patients with Barrett's Esophagus

BACKGROUND & AIMS Experimental evidence indicates that proton pump inhibitors (PPIs), nonsteroidal anti-inflammatory drugs (NSAIDs)/aspirin, and statins can protect patients with Barretts esophagus (BE) from developing neoplasias. However, only limited data are available on chemoprevention in patients with BE. METHODS A retrospective observational study was performed using data from patients with documented BE. Prescription information was collected from pharmacy records. Cox regression analyses were performed to examine the association between prescriptions for PPIs, NSAIDs/aspirin, or statins and the risk of developing esophageal dysplasia or adenocarcinoma during follow-up (from 1982 to 2005). RESULTS We examined 344 patients diagnosed with BE (mean age 61 years, 90.4% Caucasian, 94.2% male). After BE diagnosis, 67.2% of the patients were prescribed PPIs for a mean duration of 5.1 years; 49.1% were prescribed NSAIDs for a mean duration of 3.6 years, and 25.3% were prescribed statins for a mean duration of 2.8 years. During 2620 patient-years, high grade dysplasia or esophageal adenocarcinoma developed in 33 patients. PPI treatment after BE diagnosis was associated with a reduced risk of high grade dysplasia or cancer; this association persisted after adjustment for gender, age, and the length of BE. NSAID and/or aspirin therapy were associated with a nonsignificant trend toward lower incidence of high grade dysplasia or esophageal cancer. CONCLUSIONS PPI therapy reduces the risk of neoplasms in patients with BE. NSAIDs/aspirin appear to reduce cancer risk whereas statin use is not significantly associated with the risk of neoplasia in patients with BE.

Analysis of Cyclooxygenase 2 (COX-2) Expression During Malignant Melanoma Progression

Cyclooxygenase 2 (COX-2) is an inducible enzyme involved in the production of prostaglandins and thromboxanes during inflammation. There are now several lines of evidence indicating that increased expression of COX-2 plays a functional role in the development and progression of malignant epithelial cancers. However, there is only limited data regarding the role of COX-2 in melanoma pathogenesis. In the present work, we retrospectively examined lesions through out the development of melanoma and metastatic disease (dysplastic nevi n = 10, melanoma in situ n = 4, stage II melanoma n = 10, stage III n = 4, stage IV n = 3, stage V n = 2, melanoma metastasis lymph nodes n = 13 metastasis to other sites n = 3). COX-2 was consistently observed in keratinocytes, dermal fibroblasts, and inflammatory cells in regions adjacent to benign nevi and primary cutaneous melanomas. However, no COX-2 staining was detected in the nevi nor in the primary skin melanoma cells. In addition, COX-2 was undetected in all vertical and radial growth phase cases. Interestingly, 13 out of 13 of the lymph node metastasis expressed extremely high levels of COX-2 in overlying epithelium and inflammatory cells, and COX-2 was strongly detected in the metastatic cancer cells per se. For additional information on the expression of COX-2 in malignant melanoma, we determined the expression of COX-2 protein in several different melanoma cell lines. We found that 3 out of 7 of the melanoma cells over expressed COX-2 compared to normal melanocytes. Collectively, these data suggest that COX-2 may play a functional role in metastases of melanoma, and treatment with COX-2 inhibitors may be efficacious for malignant melanoma.

Predicting lymph node metastases in rectal cancer.

For properly selected rectal cancers, local excision is a sphincter-saving alternative to abdominoperineal resection. If histologic assessment of a locally excised tumor reveals ominous features, further treatment with radical resection or irradiation may be necessary to treat potential lymph node metastases. PURPOSE: We wished to determine which features, if any, were predictors of nodal metastases. METHODS: Nine histologic and morphologic features of 62 radically excised rectal cancers were reviewed to determine which factors, if any, were associated with nodal disease. RESULTS: Using a chi-squared analysis, we found worsening differentiation (P=0.0001), increasing depth of penetration (P=0.026), a microtubular configuration of 20 percent or more (P=0.023), and the presence of venous (P=0.001) or perineural invasion (P=0.002) to significantly influence nodal disease. Lymphatic invasion was witnessed too infrequently to determine significance but, when present, was associated with nodal metastases in every case. Exophytic tumor morphology, mitotic count, and tumor size were not significant predictors. An analysis of variables determined that, of all factors or combination of factors examined, Broders classification was the strongest predictor of nodal disease. CONCLUSIONS: If a rectal cancer is accessible and of small size to facilitate local excision, an in-depth histologic assessment is needed to determine if nodal metastases are likely on a statistical basis.

Long-term follow-up of intestinal metaplasia of the gastric cardia

OBJECTIVE:Recent studies have found a relatively high prevalence of gastric cardia intestinal metaplasia in individuals presenting for elective upper endoscopy. It has been hypothesized that this lesion may be a precursor of gastric cardia cancer. Our objective was to identify the incidence of dysplasia in patients with gastric cardia intestinal metaplasia.METHODS:Twenty-eight patients who had previously been identified with cardia intestinal metaplasia had follow-up examinations performed. None of the patients had dysplasia at the time of diagnosis. All had an examination at 1 yr, and 20 patients had an examination at 3 yr after diagnosis. During follow-up examinations all patients underwent vital staining with methylene blue to help identify areas of intestinal metaplasia in the cardia. Two to four biopsies were taken from blue-stained mucosa. Histological specimens were stained using a combination of hematoxylin and eosin with Alcian blue at pH 2.5.RESULTS:There were 27 men and one woman with a mean age of 69.8 yr (range, 48–83 yr). The mean length of follow-up was 2.5 yr (range, 12–46 months). Only one patient was diagnosed with dysplasia (low-grade) during the study, for an incidence of 1.4% per yr.CONCLUSIONS:The prevalence (0%) and incidence (1.4%/yr) of dysplasia in cardia intestinal metaplasia are low. Although further studies are needed, screening and surveillance for gastric cardia intestinal metaplasia is unlikely to be clinically useful for the prevention of gastric cardia cancer.

Virtual slide telepathology enables an innovative telehealth rapid breast care clinic

An innovative telemedicine-enabled rapid breast care service is described that bundles telemammography, telepathology, and teleoncology services into a single day process. The service is called the UltraClinics Process. Because the core services are at 4 different physical locations, a challenge has been to obtain stat second opinion readouts on newly diagnosed breast cancer cases. To provide same day quality assurance rereview of breast surgical pathology cases, a DMetrix DX-40 ultrarapid virtual slide scanner (DMetrix Inc, Tucson, AZ) was installed at the participating laboratory. Glass slides of breast cancer and breast hyperplasia cases were scanned the same day the slides were produced by the University Physicians Healthcare Hospital histology laboratory. Virtual slide telepathology was used for stat quality assurance readouts at University Medical Center, 6 miles away. There was complete concurrence with the primary diagnosis in 139 (90.3%) of cases. There were 4 (2.3%) major discrepancies, which would have resulted in a different therapy and 3 (1.9%) minor discrepancies. Three cases (1.9%) were deferred for immunohistochemistry. In 2 cases (1.3%), the case was deferred for examination of the glass slides by the reviewing pathologists at University Medical Center. We conclude that the virtual slide telepathology quality assurance program found a small number of significant diagnostic discrepancies. The virtual slide telepathology program service increased the job satisfaction of subspecialty pathologists without special training in breast pathology, assigned to cover the general surgical pathology service at a small satellite university hospital.