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Query: UMLS:C0019204 (hepatocellular carcinoma)
 71,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The immune system has evolved under Darwinian pressures as a defence against ubiquitous viruses. Immune surveillance against viral antigens protects the normal host. Individuals with inherited or acquired immune-deficiency disorders can become vulnerable to ubiquitous viruses and neoplasms can ensue, such as B-cell lymphoma, hepatocellular carcinoma, squamous-cell carcinoma, Kaposi's sarcoma, and carcinoma of the penis and uterine cervix. Immunodeficiency permits Epstein-Barr virus, hepatitis B virus, papillomavirus, herpes simplex virus, and cytomegalovirus to induce sustained target-cell proliferation. Each virus selects specific cellular targets bearing viral receptors and the infection leads to proliferation of the target cells rather than lysis. Various co-factors, including nutrition, exposure to tumour-promoting agents, parasitic infection, and ultraviolet light, may promote carcinogenesis. Depending on the type and severity of the immune deficiency, gradual proliferation may lead to evolution of a malignant clone. Conversion of polyclonal virally infected proliferating cells to give monoclonal malignancy is probably due to specific cytogenetic rearrangements which allow oncogene activation and endow an altered tumour cell with selective growth advantages over normal diploid cells. Prevention of viral oncogenesis may be possible by treatment of immune-deficient individuals with premalignant disorders. Immunotherapy and antiviral therapy may prevent progression of viral-induced proliferation to malignancy. The purpose of this paper is to discuss and evaluate the role of immune deficiency and viruses in the induction of malignancies commonly occurring in Africans residing in sub-Saharan Africa (Purtilo, 1976). The types of malignancies commonly occurring in this region are believed to be due to ubiquitous viruses. A failure of immune surveillance mechanisms to recognize viral antigens and abrogate proliferation of infected target cells predisposes to malignancy by increasing the chance of a proliferating cell undergoing a cytogenetic or molecular alteration which endows it with malignant characteristics. The immunological surveillance hypothesis has been elaborated during this century by Ehrlich, Thomas, Burnet, and Schwartz (reviewed by Purtilo & Linder, 1983). This hypothesis rests on several assumptions: that neoplastic cells possess unique tumour antigens: tumour antigens provoke an immune response in the host; and the immune response is protective and eliminates the tumour.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Squamous-cell carcinoma, Kaposi's sarcoma and Burkitt's lymphoma are consequences of impaired immune surveillance of ubiquitous viruses in acquired immune deficiency syndrome, allograft recipients and tropical African patients. 610 Feb 88

Twenty-one (100%) Haitians and 42 (21.5%) of 192 native black Americans autopsied in a 33-month period at Jackson Memorial Hospital, Miami, were included in this review. All autopsied materials were examined. Among the Haitians autopsied, infectious diseases accounted for 11 (52%) of 21 deaths. Toxoplasma encephalitis was the leading cause of death (five cases). Other infectious causes of death included disseminated cryptococcosis (one), disseminated cytomegalovirus diseases (one), Pneumocystis carinii pneumonia (one), chronic active hepatitis B (two), and bacterial pneumonia (one). Malignant neoplasms were also found to be causes of death and these included a single cases of each of the following: adenocarcinoma of the lung, multiple myeloma, diffuse histiocytic lymphoma, hepatoma, and Kaposi's sarcoma. Deaths of the remaining cases were due to hypertensive cardiovascular diseases (two), rheumatic heart disease (one), glomerulonephritis (one), and intimal fibroplasia of coronary arteries (one). Seven Haitian cases fulfilled the Centers for Disease Control case definition for the acquired immune deficiency syndrome (AIDS). For comparison, autopsies of black Americans were chosen from conditions that would most likely predispose them to opportunistic infections. Among the autopsies on black Americans there were no cases of opportunistic infections or Kaposi's sarcoma that were considered to be consistent with the AIDS.
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PMID:Unusual causes of death in Haitians residing in Miami. High prevalence of opportunistic infections. 634 27

The cause of human cancer is probably multifactorial and the role of viruses is unclear. The study of retroviruses has led to the identification of oncogenes responsible for transformation and tumor induction. Human viruses associated with malignancies include the JC virus (associated with progressive multifocal leukoencephalopathy) and some adenoviruses. No human malignancies have been associated with the latter group. A number of herpes viruses of lower animals have been associated with malignancies and herpes simplex virus type 2 has been associated with carcinoma of the cervix and vulva. The Epstein-Barr virus has been associated with Burkitt's lymphoma and nasopharyngeal carcinoma. Some circumstantial evidence suggests that cytomegalovirus may be associated with Kaposi's sarcoma among homosexuals. The hepatitis B virus (HBV) has been associated with hepatocellular carcinoma. The fullfillment of Koch's postulates presents ethical problems regarding man and proving the viral etiology of human malignancy. Social experiments may elucidate some of these questions. An increase in venereal herpes should be associated with an increase in carcinoma of the cervix and use of the HBV vaccine in populations with high incidences of HBV carrier states should decrease the incidence of hepatocellular carcinoma. The investigation of the retroviruses though not establishing viruses as causing human malignancies at least will improve our understanding of the malignant process.
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PMID:Viruses and human cancer. 687 Jan 84

Hyaline globules (HGs), spherical intracytoplasmic eosinophilic droplets, have been associated with a variety of conditions, including hepatocellular carcinoma, lung adenocarcinoma, and Kaposi's sarcoma, but they have not been described in cartilaginous tumors. In specimens of 60 cartilaginous neoplasms we found that 22 of 33 chondrosarcomas (67%), eight of 16 enchondromas (50%), and three of seven soft tissue chondromas (43%) exhibited HGs. HGs were seen more commonly in low grade chondrosarcoma (70%) and were relatively rare in high grade chondrosarcoma (25%). No HGs were identified in three osteochondromas, one synovial chondromatosis, or 15 normal cartilaginous tissues taken from various sites. Cartilage associated HGs ranged in size from 2 to 20 microns, were diastase resistant and periodic acid-Schiff (PAS) stain positive, demonstrated autofluorescence, and variably stained with Mallory's phosphotungstic acid-hematoxylin stain (PTAH). A panel of immunostains did not show any specific staining reactions with HGs. Ultrastructurally the HGs were spherical, non-membrane-bound bodies having complex architectural features associated with profiles of rough endoplasmic reticulum. Electron probe x-ray microanalytic (EPXMA) study showed significant peaks of sulphur and calcium. We conclude that HGs represent secretory products of probable glycoprotein nature, may accumulate in a variety of cartilaginous neoplasms, and may be seen more frequently in low grade chondrosarcomas.
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PMID:Intracytoplasmic eosinophilic hyaline globules in cartilaginous neoplasms: a surgical, pathological, ultrastructural, and electron probe x-ray microanalytic study. 752 63

The incidence of malignancies in recipients of renal transplants was compared to that in non-grafted patients on maintenance dialysis as reported to the EDTA-ERA Registry and in the general population as recorded by the cancer registries of England and Wales, of Sweden, of the (former) German Democratic Republic, and of Lombardy and Varese in Northern Italy. For tumours known to be associated with immunosuppression, namely Kaposi's sarcoma, non-Hodgkin lymphoma and the common malignancies of the skin (except melanoma), an increased incidence was confirmed for the transplanted population. Thyroid carcinoma and hepatoma were found to be more frequent in non-grafted patients on dialysis as well as after renal transplantation. An increased incidence of cancer of the cervix and of the body of the uterus was recorded only for young cohorts with a functioning graft but not for women after menopause. Most of the other malignancies had similar incidences in grafted and non-grafted populations which did not differ from those in the general populations of the cancer registries except cancer of the colon which was slightly more frequent, particularly at 10-20 years after the first transplant operation. Survival after diagnosis of cancer at the most frequent sites, such as bronchopulmonary, breast, oesophagogastric and colorectal cancer, did not differ between non-grafted patient groups on dialysis and those who developed the tumour while carrying a functioning renal transplant.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Malignancies after renal transplantation: the EDTA-ERA registry experience. European Dialysis and Transplantation Association-European Renal Association. 761 85

In the West, Kaposi's sarcoma and non-Hodgkin's lymphoma have been closely associated with HIV-induced immunosuppression. To date, however, there has been no published account of the impact of HIV infection upon malignancies prevalent in Africa where the HIV epidemic is widespread. The authors describe the pattern of malignant disorders among adult indigenous Zambians over the period 1980-89 in the attempt to discern the impact of HIV infection upon the prevailing malignancies. Histopathological and hematology records of 7836 neoplasms seen during 1980-89 at the University Teaching Hospital in Lusaka, Zambia, were analyzed. The crude incidence rate of each malignancy per 100,000 adults per year was calculated and the patterns of malignancies compared for the periods 1980-83 and 1984-89. The latter period corresponds to the advent of the HIV epidemic. Carcinoma of the cervix, Kaposi's sarcoma, bladder carcinoma, hepatoma, lymphoma, and carcinoma of the breast were the six most commonly observed tumors, occurring, respectively, among 19.6%, 7%, 6.3%, 5.8%, 4.6%, and 4.4% of cases. The crude incidence rates of Kaposi's sarcoma and carcinoma of the breast increased significantly during the last six years of the study period, with nodal KS exhibiting the most significant rise from a crude incidence rate of 0.25 per 100,000 adults per year during 1980-83 to 1.11 during 1984-89. In contrast to findings from Europe and the US, no significant increase in non-Hodgkin's lymphoma was detected in Zambia following the arrival of the HIV epidemic.
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PMID:Pattern of adult malignancies in Zambia (1980-1989) in light of the human immunodeficiency virus type 1 epidemic. 763 27

The diagnosis of malignant liver tumors has long been an important part of surgical pathology, but now with improved radiographic and biopsy techniques, the appropriate pathological identification and differentiation of malignant from benign liver lesions has become even more critical. This review discusses five examples of malignant lesions that may be underdiagnosed as benign: well-differentiated hepatocellular carcinoma, fetal and macrotrabecular hepatoblastoma, well-differentiated cholangiocarcinoma, Kaposi's sarcoma, and epithelioid hemangioendothelioma.
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PMID:Malignant liver tumors that mimic benign lesions: analysis of five distinct lesions. 777 Jun 75

Viruses implicated in the development of human cancers include hepatitis B (and C) viruses in hepatocellular carcinoma; human papillomaviruses in anogenital cancers; Epstein-Barr virus in nasopharyngeal carcinoma and Burkitt's lymphoma; human T-cell leukaemia/lymphoma viruses in adult T-cell leukaemia/lymphoma; and indirectly, human immunodeficiency viruses in Kaposi's sarcoma and B-cell lymphoma. Together, they contribute significantly to the cancer statistics in the Southeast Asian region. Neoplastic proliferation may be instigated by the presence and expression of viral oncogenes which may be integrated into the host genome and/or exist in episomal molecules. Critical viral genes may also interfere with host genes, resulting in the activation of cellular proto-oncogenes and/or the inactivation of anti-oncogenes and their products. The molecular pathogenesis of virally-induced cancers has led to major breakthroughs in the understanding of carcinogenesis at a molecular level. The occurrence of some of these viruses in a significant proportion of normal individuals suggests long latency periods necessitating multi-step co-operating events arising from multi-factorial agents such as host genetic susceptibility, immunological and hormonal status, as well as chemical and physical cocarcinogens in the environment. Successful intervention achieved with effective vaccines such as the hepatitis B vaccine and measures to severe the chain of viral transmission culminating in reduced incidence of the corresponding cancer will provide conclusive evidence for the virus-cancer relationship.
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PMID:Cancer and viruses. 810 16

The human immunodeficiency virus tat protein, a transactivator of viral and cellular genes, is suspected to be involved in the pathogenesis of acquired immunodeficiency syndrome-associated tumors. We report that transgenic mice carrying a recombinant DNA containing BK virus early region and the human immunodeficiency virus tat gene develop skin leiomyosarcomas, squamous cell papillomas and carcinomas, adenocarcinomas of skin adnexa, glands, and B-cell lymphomas. Although the incidence of hepatocellular carcinoma is low, most animals show a liver cell dysplasia of variable degree. These mice are also affected by skin lesions resembling the early stages of Kaposi's sarcoma. The transgene was detected intact in all the organs of transgenic mice, generally as multiple tandemly integrated copies. BK virus early region and tat were expressed in essentially all tissues and organs of BK virus/tat transgenic mice. This transgenic mouse model is representative of the systemic involvement of tat in human immunodeficiency virus natural infection and may be applied to investigate the role of tat in malignancies associated to acquired immunodeficiency syndrome, to study Kaposi's sarcoma pathogenesis and cell of origin, to characterize preneoplastic conditions established by tat in the skin and liver, and to assess in vivo the efficacy of antiangiogenic and anti-tat-specific drugs.
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PMID:Systemic expression of HIV-1 tat gene in transgenic mice induces endothelial proliferation and tumors of different histotypes. 822 99

We are giving an overview over the clinical features and different therapeutic options of HIV associated malignancies. There are three AIDS-defining malignancies: - Kaposi's sarcoma - Non-Hodgkin's lymphoma (NHL) - cervical cancer. In Kaposi sarcoma there is a broad therapeutic spectrum from cryotherapy to systemic chemotherapy depending on the site and stage of the Kaposi sarcoma. In NHL early therapeutic intervention is necessary because of the fast progress of the tumor. The cervical cancer in HIV-infected women seems to be more aggressive than in non-infected and also needs early therapeutic intervention. Many other tumors seem to occur more frequently in patients with HIV infection: anorectal cancer, malignant testicular tumors, lung cancer, Hodgkin's lymphoma, basal cell carcinoma, squamous cell carcinoma, and even malignant melanoma. The cancer incidence in HIV-patients seems to be higher among nonblacks. Most of the immunodeficiency associated tumors are virus induced and they are accompanied by a persistent viral infection, including HHV-8 in Kaposi's sarcoma; Epstein Barr virus (EBV) in NHL; and human papillomavirus (HPV) in cervical cancer. But there are also types of virus induced tumors which are not frequently associated with HIV-infection like the primary hepatocellular carcinoma in patients with hepatitis B virus infection.
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PMID:Clinical manifestations and therapies of AIDS associated tumors. 950 54


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