First interobserver agreement of optical coherence tomography in the bile duct: A multicenter collaborative study.

Background and study aims Optical coherence tomography (OCT) is a new technology available for evaluation of indeterminate biliary strictures. It allows under-the-surface visualization and preliminary studies have confirmed standardized characteristics associated with malignancy. The aim of this study is to evaluate the first interobserver agreement in identifying previously agreed upon OCT criteria and diagnosing of malignant versus benign disease. Patients and methods Fourteen endoscopists were asked to review an atlas of reference clips and images of eight criteria derived from expert consensus A total of 35 de-identified video clips were then evaluated for presence of the eight criteria and for final diagnosis of malignant versus benign using the atlas as reference Intraclass correlation (ICC) analysis was done to evaluate interrater agreement. Results Clips of 23 malignant lesions and 12 benign lesions were scored. Excellent interobserver agreement was seen with dilated hypo-reflective structures (0.85) and layering effacement (0.89); hyper-glandular mucosa (0.76), intact layering (0.81), and onion-skin layering (0.77); fair agreement was seen with scalloping (0.58), and thickened epithelium (0.4); poor agreement was seen with hyper-reflective surface (0.36). The diagnostic ICC for both neoplastic (0.8) and non-neoplastic (0.8) was excellent interobserver agreement. The overall diagnostic accuracy was 51 %, ranging from 43 % to 60 %. Conclusions Biliary OCT is a promising new modality for evaluation of indeterminate biliary strictures. Interobserver agreement ranged from fair to almost perfect on eight previously identified criteria. Interobserver agreement for malignancy diagnosis was substantial (0.8). Further studies are needed to validate this data.

Randomized trial of pegylated interferon alpha-2b monotherapy in haemodialysis patients with chronic hepatitis C.

BACKGROUND: Chronic hepatitis C infection is prevalent among haemodialysis patients. The goal of our study was to determine the efficacy and safety of pegylated interferon alpha-2b in haemodialysis patients with chronic hepatitis C. METHODS: We conducted a trial which randomized haemodialysis patients with chronic hepatitis C to 1.0 or 0.5 microg/kg of pegylated interferon alpha-2b subcutaneously, weekly for up to 48 weeks. End-points were sustained viral response and adverse events. Data were analysed as intention to treat and as intended per protocol. RESULTS: After 16 patients were enrolled, the study was terminated because of adverse events and modifications needed in the study design. Nine subjects were randomized to the 1.0 microg/kg group and seven subjects were randomized to the 0.5 microg/kg group. Serious adverse events requiring discontinuation of therapy occurred in five (56%) subjects in the 1.0 microg/kg group and in two (28%) subjects in the 0.5 microg/kg group (P = 0.36). The most common adverse events were hypertension and infection unrelated to neutropenia. Two (22%) subjects in the 1.0 microg/kg group, both genotype 1, had a sustained viral response, and none of the subjects in the 0.5 microg/kg group had a sustained viral response (P = 0.47). Five subjects in the 1.0 microg/kg group were able to complete 24 weeks or longer of therapy as per protocol and two (40%) were sustained responders. CONCLUSIONS: In our study group, pegylated interferon alpha-2b was poorly tolerated and was associated with substantial side effects. Sustained response rates seen with pegylated interferon in our study do not appear to be better than rates reported for standard interferon alpha-2b.