Hepatitis B surface antigen and hepatocellular carcinoma in the People's Republic of China

Safety and immunogenicity of a combined hepatitis A and hepatitis B vaccine in young healthy adults

BACKGROUND

A combination of hepatitis A and hepatitis B monovalent vaccines could offer advantages for disease control programs in terms of convenience, compliance and cost.

METHODS

Under randomized, double-blind conditions, 156 healthy young adults were divided into 3 groups to receive 1 of 3 lots of a combined hepatitis A/hepatitis B vaccine administered at months 0, 1, and 6. Safety and immunogenicity were assessed after each dose.

RESULTS

Transient and predominantly mild reactions were reported by slightly more than half the vaccinees; no serious adverse effects were relate to vaccination. One month after dose 2, all subjects had converted to the hepatitis A component. Geometric mean titers (GMTs) of antibodies of hepatitis A virus varied from 4415 to 4882 mIU/ml in the three groups. For hepatitis B, most vaccinees (73%-92%) had protective levels of antibodies to hepatitis B virus (anti-HBs) after the second dose, and all were sero-protected after the booster. Anti-HBs GMTs at month 7 ranged from 1917 to 3298 mIU/ml.

CONCLUSIONS

No statistically significant differences were observed between vaccine lots. The combined hepatitis A/hepatitis B vaccine was safe and clinically well tolerated and induced immune responses quantitatively similar to those obtained with the respective monovalent vaccines.

Hepatocellular carcinoma. A worldwide problem and the major risk factors

Male sex, age, cirrhosis, and HBsAg are the major risk factors for hepatocellular carcinoma (HCC). The geographic distribution of HCC is highly uneven, such that three distinct incidence areas are recognized. To clarify the reason(s) for this geographic variability of HCC, the risk factors in each incidence area were assessed. In parallel with the geographic distribution of HCC, HBsAg prevalence was highest in both HCC patients and in general population in Africa and Asia, where mothers of HCC patients are frequently HBsAg-positive, suggesting that hepatitis B virus hyperendemicity and perinatal infection account for the high HCC incidence in these areas. Cirrhosis, which is found on autopsy in 80% of the cases of HCC patients worldwide, is the most prevalent risk factor for HCC in areas where hepatitis B virus infection is less common. However, HBsAg carriage adds to the HCC risk carried by cirrhosis and explains the higher incidence of HCC in cirrhotics from Africa and Asia as well as elsewhere. Available data suggest that chronic HCV infection is a risk factor for cirrhosis and HCC. HBV vaccination should decrease HCC incidence rates worldwide; however, HCC prevention in regions where HBsAg carriage is infrequent may also require prevention of the other causes of cirrhosis in order for HCC rates to decline.

Biologic significance of the detection of HBsAg and HBcAg in liver and tumor from 204 HBsAg-positive patients with primary hepatocellular carcinoma

Hepatitis B virus surface and core antigens (HBsAg, HBcAg) were examined in the resected primary hepatocellular carcinoma from 204 patients who had HBsAg in serum. Ninety patients had small (less than 5 cm) and 114 had large hepatocellular carcinoma (greater than 5 cm). HBsAg was detected in hepatocellular carcinoma in 65 cases (32%) and HBcAg in 30 cases (14.7%); hepatitis B virus antigens were more frequently detected in small (HBsAg in 42.2% and HBcAg in 20%) than in large hepatocellular carcinoma (HBsAg 23.7% and HBcAg 10.5%). These results suggest that replicative forms of hepatitis B virus DNA may exist in hepatocellular carcinoma more frequently than previously believed and that the malignant hepatocytes can support hepatitis B virus replication. A lymphocytic infiltration in hepatocellular carcinoma was more often observed in hepatocellular carcinoma expressing HBsAg (71%) or HBcAg (63%) than in hepatocellular carcinoma with no detectable HBsAg (26%) or HBcAg (37%), p less than 0.01. The reaction was mild in the majority (85%) of the cases. These findings suggest that hepatitis B virus antigen expression in hepatocellular carcinoma can provoke a local immune response. The most striking finding was that patients with hepatitis B virus antigens in small hepatocellular carcinoma had a 5-year survival rate (13%) lower than that (50%) of the antigen-negative patients (p less than 0.05). In contrast, patients with a marked local immune response in hepatocellular carcinoma, regardless of the viral antigen status, had significantly better 5-year survival rates (43%) than those with no or a mild lymphocytic reaction (18%). These findings indicate that a marked immune response in hepatocellular carcinoma is a favorable prognostic sign.(ABSTRACT TRUNCATED AT 250 WORDS)

Fibrolamellar carcinoma of the liver: an immunohistochemical study of nineteen cases and a review of the literature

Hepatocellular carcinoma (HCC) is a rapidly fatal neoplasm of high worldwide prevalence. Fibromellar carcinoma (FLC), a variant of HCC, lacks the dismal prognosis of "ordinary" HCC (O-HCC) and is characterized by a diagnostic histologic appearance. The current study analyzes the clinical characteristics, immunohistochemistry, and treatment of nineteen cases of FLC. These data, together with a detailed review of the literature, further characterize this unique variant. FLC affects younger patients and lacks the male predominance of O-HCC. Also, FLC lacks specific association with cirrhosis, hepatitis B virus infection, use of oral contraceptives, and alcohol abuse, all of which are implicated in other hepatic tumors. This, along with differences in serum tumor marker prevalence (AFP, B12 binding protein) suggests that its pathogenesis differs from that of O-HCC. Despite these differences, FLC shares a common differentiation with O-HCC. The increased amounts in FLC of stainable alpha-1-antitrypsin, fibrinogen, and C-reactive protein, all of which are acute phase reactants and normal hepatocyte products, implies better differentiation of FLC cells. Finally, the better prognosis of FLC is supported by this study, since only two of the 19 patients died because of tumor. This contrasts with the reported survival of patients with O-HCC, usually measured in weeks. Hepatic transplantation may hold promise for future patients with "surgically unresectable" FLC as procedure-related complications are overcome.

Immunohistochemical characterization of 130 cases of primary hepatic carcinomas

Primary liver carcinoma (PLC) may express a certain number of markers. Here we communicate results of an analysis of five such markers (alpha-1-antitrypsin--AAT--, carcino-embryonic antigen --CEA--, alpha-fetoprotein --AFP--, and superficial --HBsAg-- and core --HBcAg-- antigens of hepatitis B virus) by means of PAP techniques in 130 cases of PLC, comparing the neoplastic tissue and the non-tumorous liver. Three variants of PLC are distinguished: hepatocarcinoma (HC) (108 cases); cholangiocarcinoma (CC) (19 cases); and three cases of hepatocholangiocarcinoma (HCC). AAT was positive in 29 HC, 2 HCC, and negative in all 19 CC. CEA appeared positive in 16 HC, 16 CC and only one HCC. AFP was positive in two HC, and negative in all CC and HCC. HBsAg displayed positivity in 15 HC and one HCC, being negative in all 19 CC. HBcAg was positive in 4 HC, and negative in all CC and HCC. HBsAg was also positive in two neoplastic emboli associated with HC. On the non-tumorous liver tissue the immunohistochemical results showed positivity for AAT and CEA, but not for AFP. Therefore the present results confirm that in the geographical area from which these tumors proceed, PLC is closely correlated with HBsAg positivity and with cirrhosis.

Iron, ferritin, hepatitis B surface and core antigens in the livers of Chinese patients with hepatocellular carcinoma

Surgically resected specimens, consisting of tumor and adjacent non-neoplastic liver tissue, were obtained from 40 patients with primary liver cancer at Zhong Shan Hospital, Shanghai Medical University, the People's Republic of China, between March 1983 and July 1984. All were hepatocellular carcinomas (HCC), one being admixed with cholangiocarcinoma. The relationship of hepatitis B virus (HBV) markers with iron and ferritin was evaluated in liver tissues from patients with primary liver cancers. The serum HBsAg (Hepatitis B surface antigen) positive rate was 80.0% (32/40). Cirrhosis was observed in 97.5% (39/40). HBsAg was identified in 82.5% (33/40) of uninvolved liver, and 35.0% (14/40) of HCC tissues (P less than 0.001). HBcAg (hepatitis B core antigen) was detected in 25.0% (10/40) of liver, and 7.5% (3/40) of HCC tissues (P less than 0.05). Stainable iron was found in 65.0% (26/40) of unaffected livers, and 10.0% (4/40) of HCC tissues (P less than 0.001). Ferritin was demonstrated in 75% (30/40) of non-neoplastic liver, and 40% (16/40) of HCC tissues (P less than 0.001). Twenty-two of 33 HCC patients (66.7%) with HBsAg positive cells in their livers also showed stainable iron. Of 16 patients positive for ferritin in HCC cells, iron was found in only two. Iron was found in nine of ten patients with HBcAg in non-neoplastic hepatocytes (P = 0.056); a finding compatible with the hypothesis that iron accumulates in cells replicating HBV. The other results indicate that: immunohistologic ferritin in HCC is not due to increased stainable iron; tumor cells may produce ferritin; polyclonal antibodies to human liver ferritin react better with non-neoplastic hepatocytes than with HCC cells; the high prevalence of HBsAg and cirrhosis in HCC suggests that HBV plays a major etiologic role in hepatocarcinogenesis in China; and one case of HCC is attributed to Schistosoma japonicum infestation via cirrhosis.

Liver cell dysplasia in cirrhosis. A serologic and immunohistochemical study

Liver cell dysplasia (LCD) was investigated for hepatitis B virus (HBV) markers, alpha-fetoprotein (AFP) and ferritin by serologic and immunohistochemical methods in 101 patients with cirrhosis. LCD was found in 30 cases (29.7%), with the highest incidence in cases of posthepatitic cirrhosis (67%). In the group of dysplastic cirrhosis (DC) 46.6% of the patients had active HBV infection (hepatitis B surface antigen [HBsAg] serum positivity) compared with 7% of the patients with nondysplastic cirrhosis (NDC) (P less than 0.01). The mean serum AFP concentration was significantly raised in the DC group compared with that in the NDC group (P less than 0.05). In seven patients with LCD at the initial biopsy, the histologic followup showed the persistence of LCD in all cases, and the development of hepatocellular carcinoma (HCC) in three cases. In serologic HBsAg-positive cases, dysplastic cells, at variance with the surrounding liver parenchyma, were almost always negative for tissue HBsAg, and always negative for tissue hepatitis B core antigens (HBcAg). AFP was never detected in either normal or dysplastic cells. Ferritin was found in all cases, but dysplastic foci displayed a lesser amount of this protein. These serologic and immunohistochemical data strongly suggest a preneoplastic significance of LCD. The importance of monitoring cirrhotic patients with LCD and particularly those with HBV infection and/or increased AFP levels with more aggressive follow-up is also stressed.

Role of the surgeon in the treatment of children's cancer

The management of children's tumors has changed significantly in the past several years. New techniques and combined surgical, chemotherapeutic, and radiation approaches are responsible for improved survival in most instances. Cooperation of the surgeon with the specialists in separate disciplines is imperative to continued advancements in neoplastic disease of childhood.

Race-related morphologic variations in hepatocellular carcinoma

In West Malaysia, hepatocellular carcinoma (HCC) is common in the Chinese and in the members of the Senoi aboriginal tribe, two racial groups with diametrically opposite life-styles. Certain fundamental differences exist between the liver tumors in the two races. In the Senoi, the tumor occurs in a younger age group and there is a greater male preponderance than in the Chinese. There is also a very close relationship between hepatitis B virus infection, chronic active hepatitis, cirrhosis, liver cell dysplasia, and HCC in the Senoi and the tumors generally present as multiple nodules studding both lobes of the liver. In the Chinese, although a relationship between hepatitis B virus infection, HCC, and cirrhosis exists, this association is not as strong as in the Senoi and the tumors are generally large and solitary. The data suggest that, although the hepatitis B virus is probably an important oncogenic agent in both racial groups, there may be a difference in the pathogenesis of HCC in the two races.

Localization of hepatitis B surface and core antigens in human hepatocellular carcinoma by immunoperoxidase methods. Replication of complete virions of carcinoma cells

The localization of hepatitis B surface antigen (HBsAg) and core antigen (HBcAg) was investigated by an indirect immunoperoxidase method in formalin-fixed, paraffin-embedded liver specimens obtained from 95 Japanese patients with hepatocellular carcinomas. Routine and immune electron microscopic examinations were done in one case. The correlation between expression of hepatitis B virus antigens in the tissue and serum hepatitis B e antigen (HBeAg)/antibody to HBeAg (anti-HBe) status was examined. Hepatitis B surface antigen was detected in the cytoplasm of noncarcinomatous hepatocytes in 28 (29.5%) cases and of carcinoma cells in 11 (11.6%) cases. Hepatitis B core antigen was stained in noncarcinomatous hepatocytes in 13 (13.7%) cases and in carcinoma cells in 4 (4.2%) cases. Hepatitis B core antigen was present mainly in the nuclei, and all HBcAg-positive cases were positive for HBsAg. The routine electron microscopic examination revealed many round particles, 25 to 30 nm in diameter both in the nuclei and in the cytoplasm, and larger particles, 40 to 45 nm in diameter in the cytoplasm of carcinoma cells. Both types of particles had reaction products of HBcAg by immunoelectron microscopic study. Therefore, it was confirmed that the former were cores and the latter were Dane particles. There was a tendency that HBeAg-seropositive cases showed localization of HBcAg in the noncarcinomatous tissue. Among four cases with positive HBcAg in carcinoma cells, two were positive for HBeAg, one was positive for anti-HBe, and the other was negative both for HBeAg and anti-HBe in the sera. The data suggested occasional production of complete hepatitis B viruses of carcinoma cells in anti-HBe-positive as well as in HBeAg-positive hepatocellular carcinomas.

Fibrolamellar hepatocellular carcinoma. An immunohistochemical and ultrastructural study

Two cases of fibrolamellar carcinoma of the liver are reported in young female patients of 12 and 21 years of age. Small amounts of perinuclear alpha-fetoprotein were found, unrelated to hyaline globules, as well as alpha 1-antitrypsin in a periglobular fashion in isolated cells. Ferritin was present in a large number of cells. Ultrastructurally, the well differentiated nature of the neoplasm was substantiated by previously unreported findings such as intercellular lumina analogous to bile canaliculi and peroxisome-like bodies containing a central crystalloid. Filamentous material resembling Mallory's type of hyaline was also found. We conclude that both immunohistochemical and ultrastructural features reflect a high degree of differentiation.

Liver cell dysplasia and hepatocellular carcinoma: a histological and immunohistochemical study

Liver cell dysplasia (LCD) was found in 28 (60%) of 47 patients with hepatocellular carcinoma (HCC); 22 (79%) of them had associated liver cirrhosis. LCD was more frequently observed in posthepatitic cirrhosis (82%) than in the other forms. Carcinoembryonic antigen (CEA), alpha-1-antitrypsin (AAT) and alpha-fetoprotein (AFP), as demonstrated by the peroxidase-antiperoxidase method, were similarly expressed both in normal and in dysplastic cells. Hepatitis B surface antigen was found in eight cases (17%), six of which were associated with LCD. HBsAg was rarely found in dysplastic cells and frequently displayed a peculiar perinuclear pattern. The possible preneoplastic role of LCD is stressed.

Hepatitis-B surface antigen and hepatocellular carcinoma in Taiwan. With special reference to types and localization of HBsAg in the tumor cells

The relationship between hepatitis B virus (HBV) infection and hepatocellular carcinoma (HCC), with or without cirrhosis, was assessed immunopathologically through the detection of tissue hepatitis B surface antigen (HBsAg) on paraffin sections of 284 biopsy and surgical specimens of HCC, which were performed from 1970 to 1979, by the indirect immunoperoxidase technique. In 190 cases with nontumorous liver tissue available for histologic and etiologic analyses, cirrhosis was identified in 69.8% (37 of 53) in needle biopsy, 67.4% (31/46) in wedge, and 30.8% (28/91) in the resection or lobectomy group. HBsAg was detected in the nontumorous liver parenchyma in 85.7% in the whole series, and 90.6% in the cirrhotic cases (96.8% in wedge and 100% in resection cases). The HBsAg positivity in the noncirrhotic cases of the resection group was 84.1% (53/63), whereas the 10 negative cases in this group were all noncirrhotic. This clearly demonstrates a strong association of HBsAg and HCC in both cirrhotic and noncirrhotic patients in Taiwan, particularly in the cirrhotic group, as evidenced by the high prevalence of HBsAg in wedge and resection series. On the other hand, the etiology in the HBsAg-negative and noncirrhotic group, which also had a less evident male predominance (male:female = 3.3:1 versus 6-19.5:1) and significantly less liver cell dysplasia than HBsAg-positive or cirrhotic groups, remains to be explained. In 223 cases where tumor tissue met the minimal requirement for analysis, HBsAg was demonstrated in 27 cases (12.1%) in the tumor cells (15% in the resection group). This investigation indicates an important etiologic role of HBV in hepatocellular carcinogenesis, and the development of HCC does not depend on the coexistence of cirrhosis in Taiwan.

Localization of hepatitis B surface antigen in hepatocellular carcinoma

The author respectively examined the localization of hepatitis B surface antigen (HBsAg) in 150 autopsy cases of hepatocellular carcinoma (HCC) with particular attention to growth pattern of HCC. Varying numbers of orcein-positive cells were observed in 42 cases (28.0%) with various distribution patterns, and all the 42 cases were confirmed with immunoperoxidase technique for HBsAg. HBsAg-positive cells were detected in HCC tissue in 10 cases (6.6%) among the 150 cases. Regarding the growth pattern of HCC in the 10 cases, many HBsAg-positive cells were seen in HCCs of the sinusoidal and replacing types, in which the hepatocytes were frequently retained in the cancerous tissue, particularly around the tumor-nontumor boundary. On the other hand, there was no HBsAg-positive cell in the encapsulated type HCC which was the most common (approximately 50%) in the present study and in which the retained hepatocytes were hardly seen. Meticulous histological observation after decoloration of the positive reaction to HBsAg in the sections treated with immunoperoxidase technique and subsequent eosin stain disclosed that HBsAg-positive cells in HCC tissue were retained hepatocytes in 9 cases, and the possibility of HCC cell was not denied in one case. Moreover, HBsAg-positive cells were never detected in tumor thrombi of the portal vein branches and pulmonary metastases.

The immune status of Singapore children to hepatitis B virus

In a cross-sectional survey of hepatitis B immune status, 458 consecutive children below the age of 12 years were studied. 37.3% of these children were positive for one of three markers, HBSAg, anti-HBS or anti-HBC. 15.5% were positive for two and 1.3% were positive for all three. 10.9% were positive for HBSAg, 27.8% for anti-HBC and 19.6% for anti-HB2. The males showed a higher HBSAg carrier rate than the females, 13.5% and 6.8% respectively. This difference was significant (p less than 0.05). This study confirmed that the Singaporeans were exposed to hepatitis B virus infection from very early in life and in order to prevent the infection, immunisation should be considered in early childhood.

Hepatocellular carcinoma. A study of 50 autopsy cases with detection of hepatitis B surface antigen in fixed tissues

Fifty patients who died of hepatocellular carcinoma (HCC) were autopsied at the Ciudad Sanitaria "1 degree de Octubre" and the Hospital de la Cruz Roja (Madrid) from 1974 to 1980. Formalin fixed paraffin-embedded autopsy tissue of liver and tumor from the 50 HCC and liver tissue from 50 liver cirrhosis (LC) and from 50 autopsy of non cirrhotic control cases were examined for the presence of cytoplasmic hepatitis B surface antigen (HBsAg). The study was carried out using orcein staining, immunoperoxidase technique (IP) and indirect immunofluorescence (IF). In livers with HCC the HBsAg was detected in the cytoplasm of the hepatocytes in 10 cases (20%) with the orcein staining and in 11 (22%) with the IP and IF techniques. In one case (2%) HBsAg was found in the cytoplasm of tumor cells with the three methods--In four cases (8%) of LC and 2 (4%) control cases cytoplasmic positive cells were found. In 41 patients with HCC HBsAg was studied in the serum by radio-immunoassay (RIA) (13 cases) and immunodiffussion (28 cases). 5 patients (12,1%) were positive and 36 (72%) were negative. In the 5 serum positive HBsAg HCC the staining methods for cytoplasmic HBsAg were positive (100%). In 36 serum negative HBsAg HCC the staining method were positive in 2 cases. The results let us to conclude that HBV is a probable important etiologic factor of HCC in our milieu. 54% of the patients with HCC had a previous history of alcohol abuse; however, histologic features compatible with an alcoholic etiology were found in only 5 cases. Nevertheless we consider that the described histopathologic findings do not exclude excess alcohol consumption as a possible etiologic factor for HCC in our series.

Primary hepatocellular carcinoma and hepatitis B virus infection in Korea

Serological evidence of hepatitis B virus (HBV) infection and serum alphafetoprotein (AFP) were assayed in sera from 112 Korean patients with primary hepatocellular carcinoma (PHC) and from 63 age- and sex-matched controls. Serological evidence of HBV infection was found in 100% of PHC patients and in 97% of controls. The majority of PHC patients (87%) were positive for hepatitis B surface antigen (HBsAg). In contrast, only 14% of control individuals were positive for HBsAg, but 82% were positive for antibody to HBsAg (anti-HBs). Hepatitis B e antigen (HBeAg) was detected in a high percentage (38%) of HBsAg-positive PHC patients, but in none of the nine HBsAg-positive control individuals. Serum AFP was detectable in 83% of PHC patients but in only one of 63 controls (1.5%). These results document that HBV infection may be the major factor in the development of PHC in this country.

Primary carcinoma of the liver: diagnosis, prognosis, and management

Hepatoma accounts for less than 2% of all cancer death in this country, but it is responsible for 10-20% lethal malignancy in Asia and Africa. There are racial differences in its clinical manifestation, association with cirrhosis and/or hepatitis viral infection, pattern of spread, and prognosis. Mass screening program in China using alpha-fetal protein test has detected earlier cases, improved resectability and cure rate. About 10-15% of the patients in this country had surgical treatment. For patients with locally advanced and unresectable carcinoma, regional therapies such as infusion chemotherapy (IA hepatic or IV portal), ligation of hepatic artery, radiotherapy (external or internal), immunotherapy, either singularly or in various combinations have been tried. Despite the availability of Adriamycin and newer combinations of chemotherapeutic agents, patients with disseminated disease rarely respond. Other than earlier diagnosis, search for more effective drugs and multinodal approaches should be continued.

Histologic growth pattern of hepatocellular carcinoma: relationship to orcein (hepatitis B surface antigen)-positive cells in cancer tissue

The histologic pattern of tumor growth at tumor-nontumor boundaries was studied in 60 livers bearing hepatocellular carcinoma. Three growth patterns, arbitrarily described as "sinusoidal," "replacing," and "encapsulated," were distinguished. Cancer cells growing in the sinusoids between liver cell cords (sinusoidal pattern) were anaplastic; those growing in an expansile fashion and acquiring a fibrous capsule (encapsulated pattern) were most differentiated; and those growing into the cord of liver cells and replacing them (replacing pattern) were differentiated to an intermediate degree. There was certain relation between the histologic growth patterns and gross morphologic features of the tumors. Test results for 20 of the 60 cases were positive for serum hepatitis B surface antigen (HBsAg), and the livers also contained orcein-positive cells. Orcein-positive cells were frequently seen at the border between tumor and parenchyma. Cells containing HBsAg as an orcein-positive inclusion were present in cancer tissue in three cases. When serial sections were made from such areas and stained alternately with hematoxylin and eosin and orcein, it was found that these cells were hepatocytes blended with cancer cells. This phenomenon was related to the growth pattern of tumor cells. Orcein-positive cells were never found in metastatic lesions.

A human hepatoma cell line (PCL/PRF/5) produces lung metastases and secretes HBsAg in nude mice

PLC/PRF/5 is a human liver cancer cell line which synthesizes hepatitis B virus surface antigen (HgsAB). These cells produced tumor in 6 of 8 (75%) congenitally athymic nude mice at 13 of 28 subcutaneous injection sites and in 13 of 14 (93%) mice inoculated intraperitoneally. Tumors were successfully transplanted to 4 of 6 additional nude mice. Tumor growth was rapid. Growth of cephalad tumors was significantly greater than for caudal tumors (0.39 mm/day versus 0.28 mm/day). Microscopic examination of tumors showed moderately well-differentiated hepatocellular carcinoma. Foci of identical cells were present in pulmonary veins in 7 of 14 tumor-bearing animals. Tumor cell karyotype was identical with that of PLC/PRF/5 cells. In addition, HBsAg was detectable in high titer in animals with extensive tumor. Biological features of PLC/PRF/5-induced tumors in nude mice appeared to closely resemble human hepatocellular carcinoma. Moreover, HBsAg may provide a marker of tumor growth.

Modern aspects of the morphology of viral hepatitis

The morphologic pathology of human viral hepatitis and its sequelae are reviewed in this article. Emphasis is placed on new information, including the current status of the pathologic diagnosis of hepatitis non-A, non-B. The article includes a discussion of aspects of the virology that are pertinent to an understanding of the significance of viral markers in the liver. A small contribution of the authors is a brief description of the neocholangiole, a duct of Hering-like structure seen following hepatic necrosis from many causes, including the severe forms of viral hepatitis.