Junichiro Taki

Ki-ras mutations and p53 protein expressions in intrahepatic cholangiocarcinomas : relation to gross tumor morphology

BACKGROUND & AIMS We previously reported that intrahepatic cholangiocarcinomas (ICCs) can be divided into three categories according to their gross appearance with possible links to biological behavior. Ki-ras and p53 gene alterations are thought to be involved in early and late phases of carcinogenesis, respectively. This study was performed to investigate the relationship between the gross appearance and genetic alterations of ICC. METHODS We examined 21 patients with ICC. Ki-ras point mutations were assessed by polymerase chain reaction/single-strand conformation polymorphism methods followed by direct DNA sequencing. Expressions of p53 protein were immunohistochemically assessed. RESULTS Ki-ras point mutations were found in 10 patients (48%), and expressions of p53 protein were detected in 4 (19%). Applying the gross classification that we previously proposed, Ki-ras mutations were prominent in the periductal extension type (4 of 6; 67%) and the spicula-forming type (6 of 10; 60%). On the other hand, none of the five mass-forming-type tumors harbored Ki-ras mutations. Expressions of p53 protein did not show any clear association with gross appearance. CONCLUSIONS Ki-ras gene alterations may be involved in the cholangiocarcinogenesis of periductal extension and spicula-forming but not mass-forming types, suggesting that the underlying processes of development are different.

Clinical characteristics and proliferating activity of intrahepatic cholangiocarcinoma

Abstract To assist in the development of new approach to the palliation and treatment of intrahepatic cholangiocarcinomas, we classified tumours into mass‐forming (MF), peri‐ductal extension (PD), and spicula‐forming (SF) types in 14 subjects who underwent surgical treatment. Lymph node metastasis and microscopic lymphatic invasion were pronounced in the PD and SF types. Furthermore, in SF type tumours the incidence of microscopic vascular and perineural invasion was high. The proliferating cell nuclear antigen labelling index, a reflection of the proliferation rate of tumour cells, was significantly higher in PD and SF types than in the MF type. The prognosis associated with the MF type tended to be better than that of the other two types.

THE ENHANCED IMMUNOSUPPRESSIVE EFFICACY OF NEWLY DEVELOPED LIPOSOMAL FK506 IN CANINE LIVER TRANSPLANTATION

Local delivery of immunosuppressants to the graft and lymphatic tissue is a potential appraoch to enhance the immunosuppressive efficacy and to alleviate systemic adverse effects simultaneously. By taking advantage of this method, we developed liposomal FK506. Previous pharmacokinetic study of liposomal FK506 indicated increased FK506 levels in the liver and spleen. Because the liver is the site of the allograft in liver transplantation and the spleen is a major lymphoid tissue, we hypothesized that liposomal FK506 would increase immunosuppressive efficacy in liver transplantation. We evaluated this hypothesis in a canine model. Orthotopic liver transplantation was performed using beagle dogs, and the recipients were divided into the following groups: group I, no immunosuppression (n = 5); group II, 0.05 mg/kg/day of FK506 i.v. in a commercially available i.v. formulation for 14 days (n = 5); and group III, 0.05 mg/kg/day of FK506 i.v. in a liposomal formulation for 14 days (n = 5). All recipients in group I died within 2 weeks. Recipients in group II died within 33 days. In contrast, three recipients in group III survived for more than 200 days (P < 0.05 versus group I or group II). In DNA analysis, splenocyte proliferation activity in group III was significantly suppressed in comparison with group II. These results suggest that liposomal FK506 markedly increase the immunosuppressive efficacy of FK506 in liver transplantation. A local immunosuppressive effect in the grafted liver and significant suppression of splenocyte proliferation might contribute to enhancement of the immunosuppressive efficacy of liposomal FK506.

Transthoracic transdiaphragmatic approach for hepatectomy of Couinaud's segments VII and VIII.

Abstract. For hepatectomy of Couinaud’s segment VII or VIII, severe compression and mobilization of the liver is required to establish the operative field via the usual transabdominal approach. Compression of the cirrhotic liver impairs hepatic and systemic blood circulation, which may cause liver dysfunction. We adopted a transthoracic transdiaphragmatic approach for hepatectomy of segment VII or VIII in cirrhotic patients to establish a good operative field without compressing the liver. The aim of this study was to evaluate the benefits of this approach. Forty-four patients with hepatocellular carcinoma (HCC) complicating liver cirrhosis who underwent limited hepatectomy of Couinaud’s segment VII or VIII were studied. The patients were randomized to two groups preoperatively: group I (n = 22), transabdominal approach; group II (n = 22), transthoracic transdiaphragmatic approach. There were no differences in preoperative liver function tests, hepatic functional reserve, or extent of tumor between the two groups. The operative time in group II was significantly shorter than that in group I (243 ± 50 versus 313 ± 80 minutes;p < 0.01). Operative blood loss in group II was also significantly smaller than that in group I (1190 ± 1098 versus 2679 ± 2267 g;p < 0.01). Serum lactate dehydrogenase levels on postoperative day 1 in group II were significantly lower than those in group I (587 ± 154 versus 791 ± 383 IU/L;p < 0.05). Major postoperative complications were significantly fewer in group II. It was concluded that the transthoracic transdiaphragmatic approach is a useful method for hepatectomy of segments VII and VIII in cirrhotic patients.

Influence of Associated Viral Hepatitis Status on Recurrence of Hepatocellular Carcinoma after Hepatectomy

Abstract. The purpose of this study was to investigate the relation between the recurrence of hepatocellular carcinoma (HCC) and the histologic status of underlying chronic liver disease from a viewpoint of multicentric hepatocarcinogenesis. Sixty-eight patients who underwent curative resection of HCC and have been followed for more than 2 years are reported. Based on the microscopic findings of the noncancerous part of the liver, the patients were divided into normal liver (N,n = 2), chronic persistent hepatitis (CPH,n = 6), chronic aggressive hepatitis (CAH,n = 31), and liver cirrhosis (LC,n = 29) according to a classification by the European Association for the Study of the Liver. Background data for the groups showed no significant differences. Recurrence was observed in none of the patients in the N and CPH groups, 26 (83.9%) of the patients in the CAH group, and 12 (41.4%) of the patients in the LC group. The cumulative disease-free survival rate of the CAH group was significantly lower than that of the CPH group (p < 0.05) and LC group (p < 0.01). This study revealed that the histologic status of the underlying chronic liver disease influenced the recurrence rate in patients with HCC. CAH was considered to be a risk factor for recurrence after resection of HCC.

Successful management of portal hypertension following artificial arterioportal shunting: Report of a case

A 63-year-old woman diagnosed as having hepatic hilar cancer underwent an extended left lobectomy of the liver with excision of the right hepatic artery which was involved by the tumor. Because the hepatic artery could not be reconstructed by direct anastomosis, an artificial arterioportal (A–P) shunt was constructed between the common hepatic artery and the portal vein. However, 4 weeks after the operation, portal hypertension with severe esophageal varices developed. Under the diagnosis of portal hypertension caused by excessive blood flow from the A–P shunt, coil embolization of the common hepatic artery was performed using an angiographic technique, following which the esophageal varices completely disappeared. This case demonstrates that portal hypertension after A–P shunting can be effectively treated with coil embolization.

Cytoimmunologic monitoring using DNA analysis in canine liver transplantation

In this experiment, we evaluated the significance of flow cytometric DNA content measurement of circulating blood mononuclear cells in early detection of canine hepatic allograft rejection. In nonimmunosuppressed controls, the SG2M% of blood mononuclear cells significantly increased on days 5–6 after liver transplantation compared with the pretransplant values (P<0.01). At the time of SG2M% elevation, microscopic examination of the graft revealed acute mild rejection. These changes in SG2M% and histological findings were observed one or two days earlier than biochemical changes indicative of liver injury. On the other hand, nonrejected cases under sufficient immunosuppression with cyclosporine or FK506 maintained low levels of SG2M% in comparison with the pretransplant values (P<0.05). The rejecting cases under insufficient immunosuppression showed significantly elevated SG2M% (P<0.05), and successful steroid pulse therapy provided to the recipients immediate normalization of SG2M% with histological restoration. Moreover, other complications such as pulmonary infection, peritonitis, and marasmus—rather than the rejection reaction—did not influence on SG2M%. These results led us to believe that flow cytometric DNA content measurement of blood mononuclear cells provides relevant and early information with respect to ongoing canine hepatic allograft rejection. The diagnostic value for differentiation between hepatic allograft rejection and infection of the transplant by hepatitic viruses needs further evaluation.

Initial hepatic metabolic function in canine liver and pancreas cluster transplantation.

In this study, initial hepatic metabolic function was evaluated by determining the arterial ketone body ratio (AKBR) and plasma amino acid concentrations in an experimental orthotopic combined hepatopancreatic transplantation (OHPT), and comparing the same values in orthotopic liver transplantation (OLT). In OHPT, AKBR decreased in the anhepatic phase and recovered to the preoperative value just 1 h after reperfusion. On the other hand, in OLT, the recovery of AKBR took 3 h after reperfusion with a significant difference compared to OHPT (P<0.05). Plasma amino acid levels, especially alanine and total free plasma amino acids increased in the anhepatic phase and recovered within 1 h of reperfusion in OHPT. However, they did not recover until 3 h after reperfusion in OLT. This rapid recovery of hepatic metabolic function in OHPT should be attributed to the order of reperfusion in which the reconstruction of arterial blood flow precedes that of portal blood flow. This model is useful for assessing the best way by which the grafted liver can control the timing, order, rate, and volume of blood that should be released.

Agarose-microeneapsulated Islet Xenotransplantation.

Discordant異種膵ラ島移植におけるアガロースマイクロカプセル化 (MC (+)) と15-Deoxyspergualin (DSG) 投与の併用効果につき検討した.雑種成犬単離ラ島を5%アガロースハイドロゲルにて, マイクロカプセル化した.6,000個膵ラ島を糖尿病BALB/cマウス, またはNODマウスの腹腔内に異種移植した.Mc (+) ラ島の平均生着日数はそれぞれ37.8日, 30.6日であり, Mc (-) 群に対し有意の生着延長効果を認めた.Mc (+) に少量のDSG投与を加えることにより, 平均生着日数は76.3日, 75.3日とさらに著明に延長した.Mc (+) 群のマウス抗イヌ抗体価レベルは, DSG投与の有無にかかわらず, 移植後50%以上となる場合も認めたが, 正常血漿糖濃度が維持され, 抗体はMc (+) ラ島に傷害をあたえなかった.アガロースマイクロカプセル化とDSG投与の併用による著明な生着延長効果を認め, 将来の異種ラ島移植におけるバイオ人工膵の有用性を示した.