Study of the changes of serum hyaluronic acid during porcine liver transplantation: influence of warm ischemia

Twelve porcine liver transplantations were performed to investigate whether serum hyaluronic acid (HA) serves as a marker of warm ischemic injury. Group 1 was a control without warm ischemia (n = 7), and pigs in Group 2 were sacrificed by intracardiac KCl injection 60 min before harvesting (n = 5). All pigs survived more than 4 days in Group 1. In Group 2, all died within 2 days due to graft failure. Arterial and hepatic venous glutamic-oxaloacetic transaminase (GOT) in Group 2 were higher after revascularization. However, there were no differences between the 2 groups in arterial and hepatic venous HA levels. HA clearance by the graft also showed no differences between the groups. Although GOT reflected the degree of warm ischemia, HA and its hepatic clearance were not influenced by warm ischemic damage. In conclusion, HA was not thought to serve as a marker of liver injury when the graft suffered from warm ischemia.

[The effects of preoperative transcatheter arterial chemoembolization (TAE) for the recurrence of hepatocellular carcinoma (HCC) from the viewpoint of consecutive tumor necrosis effect]

From 1990 to 1994, seventy-seven patients with HCC below 10 cm in tumor diameter underwent hepatic resections after TAE. They were divided into two groups: group C, complete necrosis (over 90% histologically at the maximum cutting surface of the specimen): group I, incomplete necrosis (under 90%). There were no significant differences in clinical background of patients, histopathological features and total disease-free survival rate (DFR) between the two groups. Nevertheless, DFR of patients in group C was significantly better than that of patients in group I, limiting the patients for curative resection. It was suggested that the recurrence of HCC after resection might be inhibited by curative operation following preoperative TAE with complete necrosis of tumor.

Primary malignant melanoma of the esophagus: diagnostic value of endoscopic ultrasonography

Primary malignant melanomas of the esophagus have been clinically diagnosed as exophytic tumors by esophagography and esophagoscopy. We first applied endoscopic ultrasonography to the tumors; the tumors were demonstrated as "submucosal tumors" and smooth-surfaced with clear margins, and their internal echo-architectures depended upon the tumor sizes. We consider the disease can be clinically diagnosed by the above three diagnostic modalities.

[Role of reservoirs in intraarterial chemotherapy for recurrent hepatocellular carcinoma after hepatectomy]

We conducted a retrospective study on the role of reservoirs in intraarterial chemotherapy for recurrent hepatocellular carcinoma (HCC) after hepatectomy. Ninety-two out of 170 patients with HCC who underwent hepatectomy from 1987 to 1992 in our institute were enrolled in this study. HCC recurred in 55 patients. A rate of good patency of the catheter of the reservoir at the time of recurrence was found in 72.7% of the patients. Transcatheter arterial embolization (TAE) for recurrent tumor was not feasible in 3 patients, because of occlusion of the hepatic artery (3.3% of patients with reservoir, 5.5% of patients with recurrence). Eleven patients were treated by intraarterial chemotherapy using the reservoir and TAE or TAE and PEIT (group R), and 11 patients were treated only with TAE and/or PEIT (group NR). Although there were no significant differences between the two groups in the number of recurrent lesions and operative procedures, tumor-free interval was shorter in group R. Cumulative survival rates after recurrence were not significant. The frequency of TAEs was lower in group R, which shortened the hospitalization for postrecurrence therapy. Thus, intraarterial chemotherapy using reservoir contributed to improvement of the quality of life of patients with recurrent HCC.

[A case of hepatocellular carcinoma treated by intra-arterial infusion chemotherapy using THP-adriamycin]

A 46-year-old male with unresectable hepatocellular carcinoma (HCC) comprised of severe liver dysfunction was treated by intra-arterial infusion chemotherapy through an implantable reservoir. During 39 months, a total amount of THP-ADR 420 mg, ADR 70 mg and CDDP 350 mg was infused. Through the therapy, the tumor size on the lateral segment was well controlled, and serum AFP and PIVKA-II levels were also lowered. No severe side effect was observed. The patient was treated on an outpatient basis, and a good quality of life during therapy was maintained. This case suggests that THP-ADR may play an important role in a combined intraarterial chemotherapy for advanced HCC.

Cystadenoma of the liver treated by hepatic resection

The aim of this study is to report a case of cystadenoma in the liver and to discuss the difficulty of differential diagnosis from malignant tumor and the importance of complete resection of the lesion. The patient had epigastric pain and abdominal distension. Hepatic ultrasonography, abdominal CT, magnetic resonance imaging, and angiography showed the presence of a large cystic tumor occupying the right hepatic lobe indicating malignant cystadenocarcinoma. Needle biopsy of the cyst wall with sampling of the cyst fluid was performed, which revealed no malignant cells. However, CEA and CA19-9 were markedly elevated in the cyst fluid. A right trisegmentectomy via laparotomy was performed successfully. The resected tumor was 11.5x9x9 cm in size and weighed 1,240 g. The cut surface revealed the tumor with multiple cysts, in some parts of which large papillary projections into lumina were seen. Though the gross features were similar to those of cystadenocarcinoma, the final histological diagnosis was benign cystadenoma of the liver. The postoperative course was uneventful, and the patient is in good condition six years postoperatively without evidence of recurrence of the disease.

[DNA ploidy pattern in resected human hepatocellular carcinomas from the view point of biological malignant potential]

Nuclear DNA ploidy analysis was studied in patients with hepatocellular carcinoma (HCC) who underwent hepatic resections. These patients were classified three groups according to the following prescriptions. Group A (n = 100) was a group of patients of which excluded ones treated by absolute non-curative resection, Group B (n = 43) was patients who underwent absolute curative resection or relative curative resection, and Group C (n = 81) was patients whose tumor sizes were more than 2 cm in Group A. Aneuploid pattern was found in 59 cases (59.0%) in Group A, 22 cases (51.2%) in Group B and 54 cases (66.7%) in Group C. The rate of aneuploid pattern was significantly higher in patients with carcinomas more than 2 cm in diameter, fc-inf positive growth, Stage III + IV and PCNA LI > or = 40% in Group A, those with carcinomas more than 2 cm in diameter, fc-inf positive growth, im-positive and Stage III + IV in Group B, and those with PCNA LI > or = 40% in Group C. The postoperative prognoses of patients with aneuploid pattern in Group A and Group C were significantly poorer than those of the diploid one in cumulative survival rates and survival rates after recurrence. Patients with aneuploid pattern in Group B had a poorer prognosis than those with diploid one in cumulative survival rates and disease-free survival rates. These results suggest that nuclear DNA ploidy analysis was a useful marker of biological malignant potential in resected human HCCs.

Fluted serum relating to growth of both hepatocyte and hepatocellular carcinoma cells

This study was undertaken to investigate a humoral substance contributing to both primary hepatocytes and hepatocellular carcinoma (HCC) cells in the primitive form. Peripheral blood from rat, 24 h after partial hepatectomy (PH) or sham-operation, was eluted into 50 fractions using an HPLC, and each fraction was bio-assayed. In vivo relationship between PH and tumor growth was also evaluated. Only one, approximately 100 kDa, of the 50 fractions from PH rat stimulated the growth of both types of cell, and the time-lag between PH and HCC injection also correlated significantly with tumor appearance and growth. Serum in PH rats contains certain humoral stimulator(s) contributing to growth of both hepatocyte and HCC cells.

Pathological comparison between spontaneously developed and chemically induced liver cancers in LEC rats with hereditary hepatitis

To investigate the pathological differences between spontaneously developed and chemically induced liver cancers in LEC rats with hereditary hepatitis, eight-week-old LEC rats were fed 0.06% or 0.03% of 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB) for 12 weeks, and then fed basal diet. Spontaneous liver cancers occurred in 60.4% of the LEC rats, while 3'-Me-DAB induced cancers in all LEC rats. The survival periods of chemically (0.06%) treated LEC rats were significantly shorter than non-treated rats. The chemically-induced cancers were strongly related to Edmondson classification. Metastasis and transplantability of the chemically-induced cancers were higher than spontaneous cancers. LEC rats are highly susceptible to the chemical carcinogen with the initiated status of hepatocarcinogenesis.

Evaluation of multi skin test in colorectal cancer patients and effects of serum immunosuppressive factor and cytokine production of peripheral mononuclear cells

Decreased skin reactions using five kinds of recall antigens correlate d with the stage of colorectal cancer. Immunosuppressive factors in the serum (IS index) increased with the progression of the stage in cancer patients, but interleukin (IL)-I and IL-2 production in peripheral mononuclear cells (PBMC) did not correlate with the advance of the disease. In patients with low immunosuppressive factors, the score of skin reactions was significantly higher than that in patients with high immunosuppressive factors. Increased serum immunosuppressive factors seem to reduce skin reactions in the patients. Furthermore, significant difference in skin reaction score was observed between patients with high IL-1 production of PBMC and patients with low IL-1 production of PBMC. These results suggest that skin reaction might be controlled by serum immunosuppressive factors and IL-1 production of PBMC, and that the score of skin reaction using multirecall antigens is a useful parameter to learn the host immunity in colorectal cancer.

Postoperative immunocompetence and immunosuppressive effect of rat liver tumors

To investigate the kinetics of postoperative immunocompetence and immunosuppressive effects of rat liver tumors, we examined natural killer cell cytotoxicity and blastogeneses to phytohemagllutinin-P, concanavalin A, and lipopolysaccharide on 1-, 2-, 3-, 5-, 7-, 9- and 14- postoperative days (-POD) after partial hepatectomy in tumor-bearing or healthy rats. The immunosuppressive effects of the tumor were observed on all the parameters examined, particularly from 1- to 3-POD and on 14-POD. Surgical stress induced immunosuppression in the early postoperative stage which lasted over 1 week, and the immunosuppression was seriously affected by the presence of the tumor. The present study suggests that surgery without curability is closely related to enhancement of the growth of the remaining or occult cancer, leading to worse survival.

Evaluation of surgical resection for small hepatocellular carcinomas

BACKGROUND

The surgical results for small hepatocellular carcinomas (HCCs) are not necessarily satisfactory. The resectional therapy for small HCC was evaluated to elucidate its benefits and limitations.

PATIENTS AND METHODS

Data were analyzed concerning 52 patients having small HCC of <3 cm in diameter and <3 nodules, who underwent hepatic resections from 1978 to 1989.

RESULTS

Cumulative and disease-free survival at 5 years after resection were 57% and 37%, respectively. Histologic features, such as differentiation of HCCs, pseudocapsular invasion, and ploidy pattern of nuclear DNA, appeared to be good prognostic indicators. The survival rate of the large-resection group (number of resected segments greater than number of tumor-occupying segments) was significantly better than that in the small-resection group (84% versus 48% at 5 years, P<0.05).

CONCLUSIONS

Surgical resection of small HCCs is a safe and effective therapy. A large resection appears to provide better patient survival and tumor-free survival compared to a small resection.

Analysis of the hepatocyte growth factor receptor in regeneration and oncogenesis of the liver

The c-met proto-oncogene product is the tyrosine kinase receptor for hepatocyte growth factor. To gain insights into its functions in the liver, we carried out a study of the expression and tyrosine phosphorylation status of the Met protein during hepatic regeneration and in human hepatocellular carcinomas. Following partial hepatectomy of rats, decreased expression of the proreceptor p170MET and reduced levels of tyrosine phosphorylation were seen within 12 h. These changes were still evident 7 days later. By contrast, there was no significant alteration of the Met beta subunit. The analysis of samples from 18 patients with hepatocellular carcinoma revealed that the expression of p160MET proreceptor was increased in non-cancerous areas, while that of the p145 beta MET proreceptor was significantly greater in the tumor tissue than in the non-tumor areas (p < 0.05). These findings suggest that processing of the Met proreceptor is closely associated with regeneration and carcinogenesis of the liver.

Development of a bioartificial liver with sandwiched-cultured hepatocytes between two collagen gel layers

We have been developing a multiplate type of bioartificial liver (BAL) using primary cultured hepatocyte monolayers since 1987. This BAL has been shown to prolong the survival time of anhepatic dogs and rabbits. Initially, hepatocytes were cultivated on collagen-coated plates. To increase the multiplated BAL function, a sandwich cultivation method was employed in which rat hepatocytes were cultured between two collagen gel layers and were then evaluated in both stationary and perfusion cultures. In the stationary culture, the sandwich method showed a higher activity in urea synthesis than in the other culture methods (culture on a collagen coating, culture on a collagen gel, and culture between a collagen coating and a collagen gel) for 14 days. In the perfusion culture, a BAL housing cultured hepatocytes (6.5 x 10(7) cells) in the sandwich system showed urea synthesis activity ranging from 17.5 to 22.6 micrograms/2 x 10(6) cells/90 min. This activity was maintained for 5 days in the perfusion culture. The sandwich type of cultivation is applicable to the multiplated BAL.

Selective portal vein embolization with absolute ethanol induces hepatic hypertrophy and makes more extensive hepatectomy possible

Portal vein embolization has been used recently to decrease the amount of the liver to be resected and to enhance the function of the remaining hypertrophied lobes. We have observed a strong contact destructivity of absolute ethanol and used it for portal vein embolization. The present study was performed to produce hepatic hypertrophy and to show histopathologic changes that follow ethanol embolization of rat liver. Hepatic proliferation and histopathology were studied in rats receiving low and high doses of absolute ethanol via portal vein and rats undergoing 70% hepatectomy alone. The liver weight of the unresected and unembolized lobes increased rapidly after embolization and hepatectomy. Although the increase was more rapid in the high-dose group than the low-dose group in early days, the final results were not different from each other and were almost equal to those after hepatectomy. Complete obstruction of portal venous branches and massive necrosis were the main histopathologic observations after portal vein embolization with all doses of ethanol. Because the mortality rate in the low-dose group was lower than in the high-dose group and extensive necrosis of the liver parenchyma and subsequent regeneration was sufficient, using minimum dose of ethanol was much safer. Based on the biochemical and hematologic parameters, portal vein embolization with low-dose ethanol did not impair liver function more than hepatectomy alone during the initial 14 days. Portal vein embolization with absolute ethanol makes more extensive hepatectomy possible by reducing the volume necessary to resect and preserves the function of the remaining liver.

Function of culturing monolayer hepatocytes by collagen gel coating and coculture with nonparenchymal cells

Since 1987, we have been developing a bioartificial liver (BAL) using multiplated cultured hepatocyte monolayers. With the goal of promoting hepatic functions of cultured hepatocyte monolayers, we combined the use of a collagen gel layer over the monolayers of hepatocytes and/or cocultured hepatocytes with nonparenchymal cells (NPCs). The study was divided into four groups according to culture configurations: Group 1: hepatocyte monolayer culture (control); Group 2; coculture of hepatocytes and NPCs; Group 3: hepatocyte monolayer with a overlaid collagen gel layer; and Group 4: coculture with a overlaid collagen gel layer. The culture continued for 14 days. Morphological changes and hepatic functions were evaluated by urea and albumin syntheses. The morphological status of the hepatocytes remained for 2 weeks in Groups 3 and 4. Deterioration and detachment of hepatocytes and/or NPCs started in Group 1 and 2 on the third day in culture. Significantly high urea synthesis was noted in Group 4 (p < 0.001 compared with Group 1 and 2: p = 0.0014 compared with Group 3). Although there was no significant difference in albumin synthesis among the four groups, those hepatocytes covered by the collagen gel (Groups 3 and 4) tended to secrete albumin throughout the observation period. These results indicted that the environment, although artificial (but close to the in vivo state), supplied with collagen gel and the coculture, enhanced the activities of the cultured hepatocyte monolayers. We suggest that use of cocultured hepatocytes under a collagen gel is a promising candidate for a bioreactor of multiplated BAL.

Surgical procedures in gallbladder cancer with special reference to its macroscopic appearance

To investigate the relationships of the gross appearance to cancer depth and microinvasion in gallbladder cancer, thirty-three cancers were macroscopically subgrouped: papillary (n=8), nodular (n=6), papillo-invasive (n=1), nodulo-invasive (n=11), and invasive (n=7) type, respectively. Papillary type cancers were limited to the mucosa or the muscularis propria, without microinvasion. Most nodular type cancers infiltrated to the subserosa with moderate microinvasion. The other types of cancer frequently invaded the subserosa or more, with high incidence of microinvasion. Only the papillary type cancers indicated simple cholecystectomy, the other types should be operated in accordance with infiltration depth and degree of involvement.

[Randomized controlled study on adjuvant immunochemotherapy with carmofur (HCFU) for noncuratively resected and unresected gastric cancer]

To evaluate the efficacy of adjuvant immunochemotherapy, especially the long-term administration of HCFU to patients with noncuratively resected and unresected gastric cancer, a randomized controlled study was conducted by 16 institutions in Hokkaido. After surgery, 185 patients were divided into two groups using the envelope method; group A (84 patients) treated by MMC (4 mg, twice a week, total 1 mg/kg)+OK-432 (or PSK): group B (101 patients) treated with MMC+OK-432+HCFU (600 mg, per day). The 5- and 10-year survival rates were 9.8 and 3.1% in group A, and 11.1 and 11.1% in group B (p=0.062). Better survival rates were obtained in those cases with unresected, S3, or peritoneal dissemination in group B. These results suggested the long-term administration of HCFU was effective for noncuratively resected and unresected gastric cancer.