Confocal laser endomicroscopy: a primer for pathologists.

CONTEXT: The advent of new endoscopic optical techniques is likely to change pathologists' role in diagnosis. OBJECTIVE: To describe how confocal laser endomicroscopy (CLE) works, show its advantages and limitations compared to cytohistologic biopsy, and explore how it may affect the practice of pathology. DATA SOURCES: Literature review. CONCLUSIONS: Confocal laser endomicroscopy is proving its ability to provide histology-like images of tissues in vivo to help avoid risks and costs of conventional biopsies. Confocal imaging restricts light to 1 plane, emulating a paraffin section, and topical or systemic optical contrast agents allow subcellular resolution. New contrast agents could theoretically permit molecular characterization. In vivo imaging has begun to demonstrate novel, dynamic types of diagnostic features. Decreased histologic biopsies can be anticipated for a few scenarios. Significant limitations of CLE include the inability to create a tissue archive for broad molecular classification, suboptimal contrast agents, small fields of view and shallow penetration, paucity of clinical validation studies, and problems with reimbursement. Confocal laser endomicroscopy exposes new opportunities for pathologists: CLE technologies can be exploited in pathology, and diagnostic criteria expanded based on endoscopists' discoveries. Potential synergy exists between CLE and cytology, allowing the low-magnification diagnostic architectural changes by CLE and cytomorphology to emulate the full diagnostic information in a histologic biopsy while providing an archive of material for molecular or immunohistochemical studies. Confocal laser endomicroscopy will decrease some types of biopsies, but offers an opportunity for pathologists to find new ways to provide value and improve patient care.

Gastric oncology: an update.

PURPOSE OF REVIEW: As the field of endoscopy progresses, new tools and techniques continue to be developed for gastroenterology in general and gastrointestinal oncology in particular. Some of these include enhancements in diagnostic optics such as chromoendoscopy, magnification endoscopy, and confocal laser endomicroscopy. Others include advanced therapeutics such as endoscopic mucosal resection and endoscopic submucosal dissection. In this review, we will update the reader on these latest of technologies, their benefits and risks, as well as their role in evaluating, staging, and treating gastric neoplasms, especially gastric adenocarcinoma, gastrointestinal stromal tumors, and primary gastric lymphoma. RECENT FINDINGS: Noteworthy studies in this review indicate that in properly selected patients with gastric adenocarcinoma, endoscopic submucosal dissection is a viable alternative to gastric resection with 100% 5-year survival rates; in patients with metastatic gastrointestinal stromal tumors, imatinib can provide effective treatment with reasonable outcome; and in patients with low grade mucosa-associated lymphoid tissue lymphoma, eradication therapy with antibiotics is curative with a very low recurrence rate. SUMMARY: The advances discussed in this review have significantly improved the care we can offer our patients in gastric oncology. With continued advancement in the field, it will be crucial to continue to study outcomes and safety of these techniques and to develop structured training for those looking to perform these procedures.

The clinical significance of persistently normal ALT in chronic hepatitis B infection.

BACKGROUND/AIMS: Chronic hepatitis B virus (HBV) disease is caused by both necroinflammation and active viral replication. The role of ALT levels as a predictor of liver injury has recently been questioned. The aim of the study was to determine whether normal ALT is associated with liver injury in a cohort of HBV patients undergoing liver biopsy. METHODS: This is a retrospective review of chronic HBV patients divided into 3 groups; (1) persistently normal ALT (PNALT); (2) ALT 1-1.5X ULN and (3) ALT>1.5X ULN. Multiple clinical, biochemical, virological variables were evaluated. RESULTS: One hundred and ninety-two patients met the inclusion criteria, 59 with PNALT, 26 with ALT 1-1.5X ULN, and 107 with ALT>1.5X ULN. Increasing age, higher ALT, higher grade of inflammation on biopsy, and HBeAg positivity predicted fibrosis. 18% of patients with PNALT had stage 2+ fibrosis and 34% had grade 2 or 3 inflammation. Overall 37% of patients with PNALT had significant fibrosis or inflammation. Subgroup analysis showed the majority with fibrosis belonged to the high normal ALT group and that only a minority who were young and immune tolerant had significant findings on biopsy. CONCLUSIONS: There is significant fibrosis and inflammation in 37% of patients with PNALT and a liver biopsy should be considered in patients older than 40 with high normal ALT.