Viscosity of human bile sampled from the common bile duct.

Cholestasis is a frequent gastroenterological problem, which is tackled by endoscopic procedures. Little is known about bile viscosity, a major determinant of its flow. We measured the viscosity of bile from the common bile duct during endoscopic retrograde cholangiography. Bile was aspirated immediately after cannulation of the papilla and deep-frozen. Viscosity was measured with a rotational viscometer at 37 degrees C and a broad range of shear rates (0.08-69.5 s(-1)). The majority of the 138 patients (64.5%) had bile viscosities between water (0.7 mPa.s) and the lower limit of plasma (1.1 mPa.s). In 20 patients (14.5%) it was above that of plasma (>1.4 mPa.s), and showed a non-Newtonian behaviour, i.e. the viscosity increased exponentially with decreasing shear rate. Cholecystectomized patients had a lower bile viscosity. Bile viscosities did not differ between patient groups with either choledocholithiasis, sludge, cholangitis, biliary pancreatitis, pancreatic carcinoma, or cholangiocarcinoma. We conclude that bile viscosity in the common bile duct is usually lower than that of plasma, in 15% it is higher and increases exponentially with decreasing flow rate, which may lead to a vicious cycle.

Endosonographic radial tumor thickness after neoadjuvant chemoradiation therapy to predict response and survival in patients with locally advanced esophageal cancer: a prospective multicenter phase ll study by the Swiss Group for Clinical Cancer Research (SAKK 75/02).

BACKGROUND: EUS response assessment in patients with locally advanced esophageal cancer undergoing neoadjuvant chemoradiation therapy (CRT) is limited by disintegration of the involved anatomic structures. OBJECTIVE: Predictive and prognostic values of a prospectively defined maximum tumor thickness (MTT). DESIGN: Prospective open-label phase ll study (SAKK 75/02). SETTING: Multicenter, nationwide. PATIENTS: Of 66 patients with primary CRT, 56 underwent en bloc esophagectomy. INTERVENTIONS: EUS-measured MTT before and 2-5 weeks after CRT (yMTT). MAIN OUTCOME MEASUREMENTS: Cutoffs: (1) absolute thickness (yMTT) after CRT < or = 6 mm; (2) relative reduction compared with baseline (ratio yMTT/MTT) < or = 50%. Correlation between EUS measurements and histopathologic tumor regression grade (TRG) and overall survival (OS). RESULTS: Sixteen of 56 patients were not included for EUS evaluation (10 severe stenosis, 5 MTT not measured, 1 intolerance to second EUS). Characteristics (n = 40) were as follow: median age, 60 years; squamous cell carcinoma, 42%; and adenocarcinoma (AC), 58%. Initial stage was: 10 T2N1, 3 T3N0, 26 T3N1, 1 T3Nx; 14 of 23 AC Siewert type 1. Wilcoxon rank sum test showed significant correlation of TRG1 with yMTT < or = 6 mm (P = .008) and yMTT/MTT < or = 50% (P = .003). The effect of yMTT on TRG1 was significant (P = .0193; odds ratio, 0.687 [95% CI, 0.502-0.941]). The predefined cutoff of < or = 6 mm for yMTT was predictive for TRG1 (P = .0037; Fisher exact test). After a median follow-up of 28.6 months, there was a clear trend for benefit in OS with yMTT < or = 6 mm and yMTT/MTT < or = 50%. LIMITATIONS: Small sample size. CONCLUSION: In a multicenter setting, MTT measured by EUS after CRT was highly predictive for response and showed a clear trend for predicting survival.