Evaluation of quantitative image analysis criteria for the high-resolution microendoscopic detection of neoplasia in Barrett's esophagus.

Early detection of neoplasia in patients with Barrett's esophagus is essential to improve outcomes. The aim of this ex vivo study was to evaluate the ability of high-resolution microendoscopic imaging and quantitative image analysis to identify neoplastic lesions in patients with Barrett's esophagus. Nine patients with pathologically confirmed Barrett's esophagus underwent endoscopic examination with biopsies or endoscopic mucosal resection. Resected fresh tissue was imaged with fiber bundle microendoscopy; images were analyzed by visual interpretation or by quantitative image analysis to predict whether the imaged sites were non-neoplastic or neoplastic. The best performing pair of quantitative features were chosen based on their ability to correctly classify the data into the two groups. Predictions were compared to the gold standard of histopathology. Subjective analysis of the images by expert clinicians achieved average sensitivity and specificity of 87% and 61%, respectively. The best performing quantitative classification algorithm relied on two image textural features and achieved a sensitivity and specificity of 87% and 85%, respectively. This ex vivo pilot trial demonstrates that quantitative analysis of images obtained with a simple microendoscope system can distinguish neoplasia in Barrett's esophagus with good sensitivity and specificity when compared to histopathology and to subjective image interpretation.

Practical advances in stool screening for colorectal cancer.

The rationale for screening for colorectal cancer (CRC) is well established, and several tests are currently recommended. Colonoscopy has become a popular modality in most of the United States and other countries. Despite colonoscopy being highly accurate and therapeutic, many patients prefer a noninvasive screening test. Testing stool for occult blood by the chemical guaiac reagent (gFOBT) has been available for decades and is effective at reducing mortality from CRC. However, because of limitations in sensitivity and specificity, newer fecal immunochemical tests (FITs) were developed that detect occult blood using enzyme immunoassays. Because of their improved sensitivity and specificity, FITs have replaced gFOBT for screening in many settings. Detecting neoplasia-associated genetic changes in stool has also become feasible; first-generation stool DNA tests showed greater sensitivity for CRC, with similar specificity to gFOBT. Improvements to stool DNA tests have made them more sensitive and less complex. As the performance characteristics for FIT and stool DNA tests continue to evolve, stool-based testing for CRC is expected to become a more reliable component in the armamentarium for CRC screening.

Complications of and controversies associated with percutaneous endoscopic gastrostomy: report of a case and literature review.

CONTEXT: Percutaneous endoscopic gastrostomy (PEG) is one of the most commonly performed gastrointestinal procedures, despite absence of benefit in many patients and risks associated with the procedure. Increased education of primary care physicians about the shortcomings of PEG may allow for better selection of patients to be referred for PEG placement. EVIDENCE ACQUISITION: We performed a comprehensive literature review by searching PUBMED using the search headings percutaneous enteral gastrostomy, PEG, complications, dementia, stroke, dysphagia, malnutrition, and complications. We identified English language articles from 1980 onward. The highest quality data were considered to be randomized controlled trials although given the paucity of trials in this area, we used all of the various types of literature. EVIDENCE SYNTHESIS: We based the major conclusions of this review, where possible, on the most robust literature, namely, controlled trials. However, the majority of the available literature in this field is based on case series. We attempted to maximize the use of larger case series with longer term follow-up. Case reports were used only to report on rare complications where no other literature was available. CONCLUSIONS: Despite more than 30 years of experience with PEG, numerous questions remain regarding the utility of nutrition support in many of the clinical scenarios in which PEG placement is contemplated. There is a multitude of evidence that artificial nutrition does not improve outcome or quality of life in patients with dementia who have decreased oral intake. It is likely that ethical, moral, religious, and legal considerations of family members and caregivers play a role in the decision to place a PEG in a patient with dementia despite the medical evidence demonstrating lack of benefit.

Colorectal cancer in inflammatory bowel disease.

Patients with long-standing inflammatory bowel disease have an increased risk of developing colorectal cancer (CRC). CRC risk increases with longer duration of colitis, greater anatomic extent of colitis, the presence of primary sclerosing cholangitis, family history of CRC and severity of inflammation of the colon. Chemoprevention includes aminosalicylates, ursodeoxycholic acid, and possibly folic acid. To reduce CRC mortality in IBD, colonoscopic surveillance remains the major way to detect early mucosal dysplasia. When dysplasia is confirmed, proctocolectomy is considered for these patients. Ulcerative colitis patients with total proctocolectomy and ileal pouch anal-anastomosis have a rather low risk of dysplasia in the ileal pouch, but the anal transition zone should be monitored periodically. New endoscopic and molecular screening approaches may further refine our current surveillance guidelines and our understanding of the natural history of dysplasia.