This study was performed to clarify the promoting effects of primary or secondary bile acid load on the occurrence of cholangiocarcinoma, using Syrian golden hamsters. These hamsters received subcutaneously diisopropanolnitrosamine (DIPN) once weekly for 10 weeks, and simultaneously were given a standard pellet diet (control group) containing taurocholic acid (TCA group) or deoxycholic acid (DCA group). The rates of cholangiocarcinoma at 20 weeks were 23% in the control group, 60% in the TCA group and 59% in the DCA group. There were significant differences between the control and the TCA or DCA groups (p < 0.05). The rates of proliferation of bile ductules or hyperplasia of the bile duct epithelium and the bromodeoxyuridine labeling indices of bile duct epithelial cells were high in both groups treated with bile acids, compared with those in the control group. Regarding the composition of bile acids in the intraductal bile, the TCA and DCA groups revealed a decrease in primary bile acids and an increase in DCA. These results suggest that both TCA and DCA given orally promote the occurrence of DIPN-induced cholangiocarcinoma.

Optimal dose of midazolam for sedation during spinal anesthesia was investigated. One hundred and fifteen patients for spinal anesthesia (analgesic area below Th4), 30 to 70 years old, were divided into five groups according to midazolam dose: 0.025mg/ kg (27 cases), 0.05mg/kg (25 cases), 0.075mg/kg (23 cases), 0.1mg/kg (25 cases), and 0.125mg/kg (15 cases). Responses to verbal command and ciliary reflex were significantly more depressed in the 0.05, 0.075, 0.1, and 0.125mg/kg groups than in the 0.025mg/ kg group. The sedative effect of 0.025mg/kg of midazolam was therefore considered to be weak. In more than 25% of cases in the 0.075, 0.1, and 0.125mg/kg groups, respiration was depressed by dropped tongue. Respiratory rate increased significantly in the 0.1 and 0.125mg/kg groups. The numbers of cases who required vasopressor, who had body motion or nausea and vomiting did not differ much among the five groups.Blood pressure was more stable in the 0.025 and 0.05mg/kg groups than in the other three groups.The stabilities of circulation and respiration were better in the 0.025 and 0.05mg/kg groups than in the others.It was concluded that the optimal dose of midazolam for sedation during spinal anesthesia in patients aged 30-70 years is 0.05mg/ kg.

We report herein two cases of carcinoma in situ of the gallbladder associated with cholesterosis. The patient in case 1 was an 81-year-old man who underwent a cholecystectomy for cholelithiasis. The resected specimens revealed gallbladder cancer in the fundus which was diagnosed histologically as mucinous carcinoma. Other findings included 13-mm, 12-mm, and 5-mm polypoid lesions in the neck of the gallbladder which macroscopically appeared to be cholesterol polyps, but histologically demonstrated carcinoma in situ with cholesterosis. The patient in case 2 was a 76-year-old man in whom ultrasonography revealed a highly echogenic, elevated lesion in the gallbladder. Cholecystectomy was performed, and a 33 x 28-mm papillary, elevated lesion with cholesterosis was resected from the neck of the gallbladder. Histologically, this was demonstrated to be papillary adenocarcinoma in situ with cholesterosis surrounded by glandular dysplasia. The distribution of the carcinomas and cholesterosis in both of these patients suggests that the adenoma or carcinoma of the gallbladder had occurred first. Then, the tumor epithelium absorbed cholesterol from the bile, and foamy cells were produced. Thus, when treating cholesterol polyps, it should be remembered that it is often difficult to distinguish between cholesterol polyp and gallbladder cancer with cholesterosis.

This study was performed to clarify the influence of incomplete bile duct obstruction (IBDO) on the occurrence of cholangiocarcinoma, using Syrian golden hamsters. These hamsters underwent simple laparotomy (SL) or IBDO at the choledochus and received diisopropanolnitrosamine (DIPN) once weekly for 20 weeks (SL-DIPN or IBDO-DIPN groups). Histological examination in the liver showed increased bile ductules, goblet cell metaplasia of the bile duct epithelium and cholangiocarcinoma in the two groups. The occurrence rates of cholangiocarcinoma at 20 weeks were 35% in the SL-DIPN group and 89% in the IBDO-DIPN group (p <0.01). The mean numbers of tumors per hamster in the IBDO-DIPN group were significantly higher than those in the SL-DIPN group (p <0.01). Regarding the composition of bile acid in the intraductal bile, both groups revealed an increase in primary bile acid, consisting of more than 80% of cholic acid. Bacteria were detected in the group with IBDO throughout the whole course. These results suggest that IBDO has an influence as promoter on the occurrence of DIPN-induced cholangiocarinoma.

We report a case of anomalous junction of the pancreaticobiliary duct (AJPBD) associated with gallbladder cancer and obstructive jaundice in a patient with high serum and bile cytokine levels. The patient was a 63-year-old woman who complained of right hypochondralgia. Ultrasound, computed tomography, percutaneous transhepatic cholangiography, and endoscopic retrograde cholangio-pancreatatography revealed dilation of the bile ducts, an elevated lesion of the gallbladder, and AJPBD. She underwent percutaneous transhepatic cholangio-drainage (PTCD) for obstructive jaundice. However, the total bilirubin concentration remained high 7 days after PTCD. Her serum interleukin 6 level was 57,359 pg/ml before PTCD, and gradually decreased to 10 pg/ml after PTCD. Bile interleukin 6 level was 10 pg/ml before PTCD, 8997 pg/ ml 3 h after PTCD and gradually decreased there after. Serum and bile levels of tumor necrosis factor alpha and hepatocyte growth factor were high before and after PTCD. The patient underwent an extended cholecystectomy and resection of the extrahepatic bile duct. The resected specimen showed two elevated lesions of the gallbladder which, microscopically, revealed moderately differentiated tubular adenocarcinoma. These findings suggest that pre-existing inconspicuous inflammation of the biliary tract due to reflux of pancreatic juice is involved in elevation of serum and bile cytokines, and that cytokines may participate in gallbladder carcinogenesis associated with AJPBD.