Sum of the longest diameters of metastatic liver tumors is a possible new prognostic factor after hepatectomy in patients with colorectal liver metastases.

BACKGROUND/AIMS: Although the size and number of the metastatic liver tumors have been considered to be prognostic factors after hepatectomy in patients with colorectal liver metastases, the importance of these parameters is still controversial. The aim of this study was to evaluate the importance of the new factor, namely, the sum of longest diameters of the metastatic liver tumors (SLD). METHODOLOGY: The medical records of 59 patients who had undergone hepatic resection for colorectal liver metastases were abstracted and these patients were completely followed-up. RESULTS: The overall 5-year survival rate after hepatectomy was 38.5%, and median survival time was 25.9 months. The significant prognostic factors by the univariate analysis were the extents of vessel permeation and lymph node metastasis of primary colorectal carcinoma, the presence of extrahepatic metastasis, the longest diameter and SLD of the liver tumor, surgical margin of the liver, and the serum level of carcinoembryonic antigen. Multivariate analysis showed that SLD (P=0.026) and extrahepatic distant organ metastasis (P=0.008) were the independent prognostic factor. CONCLUSIONS: SLD is a useful and significant predictor for survival after hepatectomy in patients with colorectal liver metastases.

Species difference in cholesterol 7alpha-hydroxylase expression of rabbit and rat liver microsomes after bile duct ligation.

BACKGROUND: Bile duct ligation (BDL) produces a good animal model for investigation of the metabolic changes in obstructive jaundice. The aim of this study was to investigate the species difference in expression of cholesterol 7alpha-hydroxylase (7alpha-hydroxylase) in rabbits and rats after BDL. MATERIALS AND METHODS: Ten male New Zealand white rabbits weighing 2.5-3 kg and 12 male Wistar strain rats weighing 250-300 g were used. Half the animals underwent BDL, and half were sham operated (Sham). The animals were sacrificed on day 5 after operation. The livers were harvested, and levels of mRNA and 7alpha-hydroxylase activity were determined. Concentrations of serum bilirubin and bile acids were also measured. RESULTS: In BDL rats, the levels of mRNA were increased 30%, and 7alpha-hydroxylase activity was three times that of the Sham group. In BDL rabbits, however, these values were approximately 60 and 50% lower than the Sham group, respectively. Serum bile acid concentrations increased up to 13 times in BDL rabbits and 70 times in BDL rats over that of the Sham groups. Serum cholesterol and serum total bilirubin concentration also increased after BDL in both animals. CONCLUSION: These results suggest that there is a species difference in the expression of 7alpha-hydroxylase after BDL in rabbits and rats and the reason for this difference is most likely pretranslational regulation.

Primitive neuroectodermal tumor of the transverse colonic mesentery defined by the presence of EWS-FLI1 chimeric mRNA in a Japanese woman.

We report a case of primitive neuroectodermal tumor (PNET) arising in the transverse colonic mesentery. A 24-year-old Japanese woman was admitted to Kagoshima City Hospital with complaints of abdominal pain and sensations of abdominal fullness of 5 months' duration. On palpation, a mass the size of an infant's head was noted in the right flank. Abdominal computed tomography (CT) and ultrasonography showed a huge mass that consisted of multiple cystic components. On arteriography, a slight tumor stain appeared, with stretched and displaced tributaries of the right colic and middle colic arteries. Barium swallow examination demonstrated that the ascending colon was shifted to the right and small intestine to the left. We performed an en-bloc resection of the tumor in the transverse colonic mesentery, including the ascending colon, proximal jejunum (20 cm in length), and greater omentum. The resected tumor was 12 x 10 x 7 cm in size, 590g in weight, elastic soft in consistency, and multicystic. Histologically, the specimens showed a sheet-like proliferation of spindle-to-polygonal cells, and focally, the tumor formed rosette structures. Immunohistochemically, the tumor cells were positive for neuron-specific enolase (NSE) and mic-2. EWS-FLI1 chimeric mRNA was detected by reverse transcriptase-polymerase chain reaction (RT-PCR). Based on the above findings, we finally diagnosed the tumor as PNET of the colonic mesentery. There has been no recurrence for 20 months after operation. PNET arising in the mesentery is very rare, and we distinguished PNET from other tumors by immunohistochemical examination and by demonstration of the presence of EWS-FLI1 chimeric mRNA in the tumor.

A comparative study of the conversion of 7-hydroxycholesterol in rabbit, guinea pig, rat, hamster, and chicken.

The metabolism of epimeric 7-hydroxycholesterol was studied in vitro. 7Alpha-hydroxycholesterol or 7beta-hydroxycholesterol were incubated with rabbit, guinea pig, rat, hamster, and chicken microsomal suspensions and then extracted and analyzed using high-performance liquid chromatography (HPLC). 7Alpha-hydroxy-4-cholesten-3-one was the main product from 7alpha-hydroxycholesterol in the rabbit, guinea pig, and rat. A considerable amount of 7-ketocholesterol was also produced in the hamster and chicken. In all vertebrates, 7beta-hydroxycholesterol was converted only to 7-ketocholesterol in all vertebrates. 7Beta-hydroxy-4-cholesten-3-one was not detected. Reduction of 7-ketocholesterol was also studied in the rat and hamster. Whereas 7-ketocholesterol was converted to 7beta-hydroxycholesterol in the rat, it was converted to both 7alpha- and 7beta-hydroxycholesterol in the hamster. These results suggest that 7alpha-hydroxycholesterol is converted not only to 7alpha-hydroxy-4-cholesten-3-one but also to 7-ketocholesterol in the hamster and chicken. 7Beta-hydroxycholesterol was converted to 7-ketocholesterol in all vertebrates tested. The interconversion between 7alpha- and 7beta-hydroxycholesterol via 7-ketocholesterol was observed in the hamster in this in vitro study.