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A C Paterson

Publications and source records attributed to A C Paterson.

29 records · Page 2Linked to original sources

Smoking as a risk factor in hepatocellular carcinoma. A case-control study in southern African blacks.

Two hundred forty southern African black patients with hepatocellular carcinoma and control subjects matched for race, sex, age, and urban or rural background were questioned about their smoking habits. Patients with hepatocellular carcinoma were not more likely to smoke or to smoke heavily than the control subjects. This was also true of the subgroups: men and women, and urban and rural background. There was a slightly increased relative risk associated with smoking in all patients who showed no serum markers of current or past hepatitis-B virus infection and in patients older than 50 years who did not have markers of current or past hepatitis-B virus infection. However, this was not statistically significant, and was not supported by a linear trend, the risk in heavy smokers being less than 1. Rural black patients, who have a higher incidence of hepatocellular carcinoma than urban black patients, smoked less than their urban counterparts. We conclude that smoking is not an unqualified risk factor for hepatocellular carcinoma in southern African black patients. There may, however, be a trend toward smoking playing an etiologic role in patients without hepatitis-B virus infection, especially in older patients.

Adult↗

The liver in biliary obstruction due to chronic pancreatitis.

Biliary obstruction is an important complication of chronic calcifying pancreatitis. In this study, liver biopsies were examined to determine the nature and severity of hepatic complications in 23 such cases. The most striking changes were portal tract expansion due to oedema and fibrosis, with proliferation of bile ducts. Although common, these changes were not severe, and no patient had developed secondary biliary cirrhosis. Other features of note were intrahepatic cholestasis, iron overload (56.5%), copper-associated protein stained with the orcein technique (34.7%) and mild fatty change or perivenular sclerosis in 13%. It is concluded that no serious, irreversible pathological changes occurred in the liver despite clinically marked biliary obstruction.

Adult↗

Hepatitis-B virus infection in black children with hepatocellular carcinoma.

The hepatitis B virus (HBV) status of six unselected South African Black children, aged 10 to 16 years, with hepatocellular carcinoma (HCC) was investigated. The characteristics of the tumor were similar to those seen in Black adults. Hepatitis B surface antigen and antibody to the core antigen were present in the serum of all the children, and hepatitis Be antigen was detected in four of the children. The serum of the two patients without e antigen was positive for e antibody, and all sera were negative for hepatitis B surface antibody. Taken in conjunction with the HBV status of southern African Black adults with HCC, these findings raise the possibility that nearly all, if not all, Black patients with this tumor are or have been infected with HBV. Moreover, if HBV is oncogenic, tumor formation may occur within 10 years of the initial infection, which occurs in early childhood in southern African Blacks.

Adolescent↗

Hepatocellular carcinoma in an urbanised black community. A changing pattern.

Hepatocellular carcinoma has been extensively studied in Southern Africa, and particularly its relationship to hepatitis B virus infection. Most of this work involved rural Black populations. In this study the impact of urbanization on this relationship is investigated. The material is derived from the laboratory records at Baragwanath Hospital which serves the Black urban community of Soweto, Cases autopsied during the periods 1956-1960 and 1976-1980 have been examined with regard to age, sex, underlying cirrhosis and presence of HBsAg in the non-tumour liver. In addition, all biopsies from 1955 to 1980 have been analysed with respect to age and sex. There is evidence of a significant increase in overall average age and in the proportion of female cases, while the percentage of HBsAg positive cases has fallen. Possible causes for these findings are considered.

Adult↗

Foreign-body ileitis. A case report.

A patient who ingested a soft-drink bottle top and stones, which resulted in a chronic active ileitis, is described. Histological examination revealed a chronic active inflammatory process, probably indicating long-term ingestion of foreign material. The histological features in some respects resembled those of Crohn's disease.

Adult↗

Hepatitis B surface antigen and hepatocellular carcinoma in Southern Africa.

Most series in Africa show a high percentage of hepatitis B surface antigen in hepatocellular carcinoma. Two groups of cases were investigated in this study. The one was derived from the autopsy material at Baragwanath hospital from subjects who had lived in Soweto, a large Black urban town. The second group consisted of male Black mineworkers generally originating from rural areas. A combination of the aldehydefuchsin stain and immunoperoxidase technique was used. The two groups showed totally different results. The Baragwanath series consisted of 24 hepatocellular carcinomas of which only 4 (17%) were HBsAg positive. Of the 24 cases, 14 had cirrhosis of which 9 were macronodular and 5 micronodular. Ten of these cases showed heavy iron overload. The series of male Black mineworkers comprised 22 cases of which 16 (72%) were HBsAg positive. Twelve of the 22 cases showed a macronodular cirrhosis and there were no micronodular cirrhoses. Only one case showed severe iron overload. These findings delineate two different populations of hepatocellular carcinoma in Southern Africa.

Adult↗

Liver morphology in southern African blacks with hepatocellular carcinoma: a study within the urban environment.

Hepatocellular carcinoma has a lower prevalence and presents at a later age in urban Blacks than in rural Blacks. These differences have previously been shown not to be attributable to differences in serum hepatitis B virus markers. In the present study, the average age of patients with hepatocellular carcinoma in a developing urban Black population is shown to have risen from 38.9 to 56.5 years (p less than 0.0001) over a 20-year interval, while the prevalence of co-existing cirrhosis has declined from 66 to 44% (p less than 0.05) and tissue HBsAg positivity has fallen from 44 to 17.7% (p = 0.002). The lower prevalence of tissue HBsAg in the recent patients may be explained by their older age. Macronodular cirrhosis was present in 56% of cases in the earlier period but declined to 18.9% in the later period, with micronodular cirrhosis becoming the dominant nontumor pathology (p = 0.002). Liver damage attributable to the abuse of alcohol is now found in more than half of the cases (48/90) of hepatocellular carcinoma occurring in this population. The remainder show no changes (12 cases) or show macronodular or incomplete septal cirrhosis (30 cases), presumed to be of viral origin. The latter cases are more likely to have serum markers of current hepatitis B virus infection than those with evidence of alcohol abuse. We conclude that alcohol is increasing in importance as an etiologic association of hepatocellular carcinoma in urban South African Blacks. At the same time, the prevalence of macronodular cirrhosis (and of cirrhosis as a whole) in urban patients with this tumor has declined. The reason for this decline is not known.

Adult↗

Lack of hepatic transferrin receptor expression in hemochromatosis.

The major part of hepatocellular iron is derived from uptake of transferrin-bound iron by means of nonspecific fluid-phase endocytosis and specific, saturable binding on high-affinity transferrin receptors. We investigated the expression of transferrin receptors on hepatocytes in liver biopsies of 22 cases of hemochromatosis (21 primary hemochromatosis and 1 secondary hemochromatosis), using immunohistochemical demonstration of the human transferrin receptor with the specific monoclonal antibody OKT9. Fifty liver biopsies (normal and pathological) without demonstrable iron storage (Perls' stain negative) served as controls. In the controls, membranous and/or cytoplasmic transferrin receptor expression was always present on hepatocytes, albeit in variable numbers and patterns without obvious relation to the underlying liver disease. In 19 of 22 hemochromatosis cases with severe iron overload, OKT9 immunoreactivity on hepatocytes was completely absent. Three hemochromatosis cases showed few hepatocytes positive for OKT9. One showed mild iron overload, while the second, a successfully treated case, was free of iron. The remaining hemochromatosis case was a known alcoholic with severe iron overload. Since OKT9 binding to the transferrin receptor is not blocked by previous binding of transferrin, the findings show that in advanced hemochromatosis hepatocytes do not express transferrin receptors. This finding is in keeping with the inverse relation between transferrin receptor expression and exogenous iron supply in various cell cultures. These results indicate that in hemochromatosis,apparently as a result of progressive iron overload,transferrin receptor expression on hepatocytes disappears.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Membranous obstruction of the inferior vena cava and invasion of the inferior vena cava by tumour in hepatocellular carcinoma.

A 28 yr old Zulu presented with a painful swelling in the right hypochondrium and severe swelling of the legs of short duration. The serum alpha-fetoprotein concentration was over 2 X 10(5) ng/ml and imaging showed a large hepatic mass-lesion. Radionuclide venography revealed no flow through the inferior vena cava but flow through a large collateral vessel. Contrast venography showed the upper portion of the inferior vena cava to be occluded: large collateral vessels arose from the lower vena cava and the iliac veins. The histological features were those of longstanding hepatic venous outflow obstruction with irregular centrizonal and portal fibrosis: severe acute centrizonal congestion was not seen. This combination of findings indicates the presence of both membranous obstruction of the inferior vena cava, a rare developmental abnormality which predisposes to hepatocellular carcinoma formation, and invasion by the tumour of the inferior vena cava via the hepatic veins, an uncommon complication of hepatocellular carcinoma.

Adult↗