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1.
PLoS One ; 13(5): e0196057, 2018.
Article in English | MEDLINE | ID: mdl-29718992

ABSTRACT

OBJECTIVE: The aims of this study were to determine the prevalence of risk factors associated with hepatocellular carcinoma (HCC) in black adult South Africans and to estimate the size of the associated risks. METHODS: A case-control analysis of 150 black South African patients (aged 18-75 years) with HCC-who were a subset of patients recruited for the Johannesburg Cancer Case Control Study 2000 to 2012-was undertaken. The association between this tumour and hepatitis B/C virus infections, and human immunodeficiency virus (HIV) mono- and co-infections was investigated. Odds ratios (ORs) and 95% confidence intervals (CI) adjusted for age, year of diagnosis, marital status, place of birth and selected modifiable risk factors were calculated. RESULTS: HCC was significantly associated with a rural birthplace (p<0.05), being male and living in an urban area for 14 years or less. The Odds Ratio (OR) for HCC increased significantly with HBV DNA+/HBsAg+ (OR 34.5; CI:16.26-73.13), HBV DNA+/HBsAg- (OR 3.76; CI:1.79-7.92), HBV DNA level >2000 IU/ml (OR 8.55; CI:3.00-24.54) to ≥200,000 (OR 16.93; CI:8.65-33.13), anti-HCV (OR 8.98; CI:3.59-22.46), HBV DNA+/HIV+ co-infection (OR 5.36; CI:2.59-11.11), but not with HBV DNA-/HIV+ (OR 0.34; CI:0.14-0.85). We did not find a synergistic interaction between HBV and HIV. Modifiable risk factors (alcohol consumption, tobacco smoking, number of sexual partners, diabetes and hormonal contraceptive use) were nonsignificant. DISCUSSION: A considerable portion of the HCC burden in Johannesburg and surrounding provinces falls on rural migrants to urban areas, most of whom are men. The HBV will continue to contribute to HCC incidence in older age-groups and in others who missed vaccination. Although we did not find an increased risk for HCC in HIV positive individuals this may change as life expectancy increases due to greater access to antiretroviral therapies, necessitating the addition of hepatitis virus screening to preventive medical care.


Subject(s)
Black People/statistics & numerical data , Carcinoma, Hepatocellular/ethnology , Carcinoma, Hepatocellular/epidemiology , Liver Neoplasms/ethnology , Liver Neoplasms/epidemiology , Adolescent , Adult , Aged , Case-Control Studies , Female , Humans , Male , Middle Aged , Risk Factors , South Africa/epidemiology , South Africa/ethnology , Young Adult
2.
Int J Cancer ; 139(1): 85-98, 2016 Jul 01.
Article in English | MEDLINE | ID: mdl-26529033

ABSTRACT

Epidemiological and mechanistic evidence on the causative role of human papillomaviruses (HPV) in esophageal squamous cell carcinoma (ESCC) is unclear. We retrieved alcohol- and formalin-fixed paraffin-embedded ESCC tissues from 133 patients seropositive for antibodies against HPV early proteins, from high-incidence ESCC regions: South Africa, China and Iran. With rigorous care to prevent nucleic acid contamination, we analyzed these tissues for the presence of 51 mucosotropic human alpha-papillomaviruses by two sensitive, broad-spectrum genotyping methods, and for the markers of HPV-transformed phenotype: (i) HPV16/18 viral loads by quantitative real-time PCR, (ii) type-specific viral mRNA by E6*I/E6 full-length RT-PCR assays and (iii) expression of cellular protein p16(INK4a). Of 118 analyzable ESCC tissues, 10 (8%) were positive for DNA of HPV types: 16 (4 tumors); 33, 35, 45 (1 tumor each); 11 (2 tumors) and 16, 70 double infection (1 tumor). Inconsistent HPV DNA+ findings by two genotyping methods and negativity in qPCR indicated very low viral loads. A single HPV16 DNA+ tumor additionally harbored HPV16 E6*I mRNA but was p16(INK4a) negative (HPV16 E1 seropositive patient). Another HPV16 DNA+ tumor from an HPV16 E6 seropositive patient showed p16(INK4a) upregulation but no HPV16 mRNA. In the tumor tissues of these serologically preselected ESCC patients, we did not find consistent presence of HPV DNA, HPV mRNA or p16(INK4a) upregulation. These results were supported by a meta-analysis of 14 other similar studies regarding HPV-transformation of ESCC. Our study does not support the etiological role of the 51 analyzed mucosotropic HPV types in the ESCC carcinogenesis.


Subject(s)
Carcinogenesis/genetics , Carcinoma, Squamous Cell/virology , Esophageal Neoplasms/virology , Human papillomavirus 16/pathogenicity , Human papillomavirus 18/pathogenicity , Aged , Carcinoma, Squamous Cell/epidemiology , Carcinoma, Squamous Cell/genetics , China , Esophageal Neoplasms/epidemiology , Esophageal Neoplasms/genetics , Esophageal Squamous Cell Carcinoma , Female , Genotype , Human papillomavirus 16/genetics , Human papillomavirus 18/genetics , Humans , Iran , Male , Middle Aged , Oncogene Proteins, Viral/genetics , Repressor Proteins/genetics , South Africa
3.
BMC Cancer ; 15: 144, 2015 Mar 18.
Article in English | MEDLINE | ID: mdl-25884599

ABSTRACT

BACKGROUND: HIV infection is a known risk factor for cancer but little is known about HIV testing patterns and the burden of HIV infection in cancer patients. We did a cross-sectional analysis to identify predictors of prior HIV testing and to quantify the burden of HIV in black cancer patients in Johannesburg, South Africa. METHODS: The Johannesburg Cancer Case-control Study (JCCCS) recruits newly-diagnosed black cancer patients attending public referral hospitals for oncology and radiation therapy in Johannesburg . All adult cancer patients enrolled into the JCCCS from November 2004 to December 2009 and interviewed on previous HIV testing were included in the analysis. Patients were independently tested for HIV-1 using a single ELISA test . The prevalence of prior HIV testing, of HIV infection and of undiagnosed HIV infection was calculated. Multivariate logistic regression models were fitted to identify factors associated with prior HIV testing. RESULTS: A total of 5436 cancer patients were tested for HIV of whom 1833[33.7% (95% CI=32.5-35.0)] were HIV-positive. Three-quarters of patients (4092 patients) had ever been tested for HIV. The total prevalence of undiagnosed HIV infection was 11.5% (10.7-12.4) with 34% (32.0-36.3) of the 1833 patients who tested HIV-positive unaware of their infection. Men >49 years [OR 0.49(0.39-0.63)] and those residing in rural areas [OR 0.61(0.39-0.97)] were less likely to have been previously tested for HIV. Men with at least a secondary education [OR 1.79(1.11-2.90)] and those interviewed in recent years [OR 4.13(2.62 - 6.52)] were likely to have prior testing. Women >49 years [OR 0.33(0.27-0.41)] were less likely to have been previously tested for HIV. In women, having children <5 years [OR 2.59(2.04-3.29)], hormonal contraceptive use [OR 1.33(1.09-1.62)], having at least a secondary education [OR:2.08(1.45-2.97)] and recent year of interview [OR 6.04(4.45-8.2)] were independently associated with previous HIV testing. CONCLUSIONS: In a study of newly diagnosed black cancer patients in Johannesburg, over a third of HIV-positive patients were unaware of their HIV status. In South Africa black cancer patients should be targeted for opt-out HIV testing.


Subject(s)
HIV Infections/diagnosis , HIV-1 , Lymphoma, Non-Hodgkin/virology , Sarcoma, Kaposi/virology , Attitude to Health , Black People , Case-Control Studies , Cost of Illness , Cross-Sectional Studies , Female , HIV Infections/complications , HIV Infections/epidemiology , Humans , Lymphoma, Non-Hodgkin/epidemiology , Male , Mass Screening , Middle Aged , Prevalence , Sarcoma, Kaposi/epidemiology , South Africa
6.
Prostate Cancer ; 2014: 419801, 2014.
Article in English | MEDLINE | ID: mdl-24955252

ABSTRACT

Prostate cancer is one of the most common male cancers globally; however little is known about prostate cancer in Africa. Incidence data for prostate cancer in South Africa (SA) from the pathology based National Cancer Registry (1986-2006) and data on mortality (1997-2009) from Statistics SA were analysed. World standard population denominators were used to calculate age specific incidence and mortality rates (ASIR and ASMR) using the direct method. Prostate cancer was the most common male cancer in all SA population groups (excluding basal cell carcinoma). There are large disparities in the ASIR between black, white, coloured, and Asian/Indian populations: 19, 65, 46, and 19 per 100 000, respectively, and ASMR was 11, 7, 52, and 6 per 100 000, respectively. Prostate cancer was the second leading cause of cancer death, accounting for around 13% of male deaths from a cancer. The average age at diagnosis was 68 years and 74 years at death. For SA the ASIR increased from 16.8 in 1986 to 30.8 in 2006, while the ASMR increased from 12.3 in 1997 to 16.7 in 2009. There has been a steady increase of incidence and mortality from prostate cancer in SA.

8.
PLoS Med ; 9(3): e1001182, 2012.
Article in English | MEDLINE | ID: mdl-22412354

ABSTRACT

BACKGROUND: Oral contraceptives are known to influence the risk of cancers of the female reproductive system. Evidence regarding the relationship between injectable contraceptives and these cancers is limited, especially in black South Africans, among whom injectable contraceptives are used more commonly than oral contraceptives. METHODS AND FINDINGS: We analysed data from a South African hospital-based case-control study of black females aged 18-79 y, comparing self-reported contraceptive use in patients with breast (n = 1,664), cervical (n = 2,182), ovarian (n = 182), and endometrial (n = 182) cancer, with self-reported contraceptive use in 1,492 control patients diagnosed with cancers with no known relationship to hormonal contraceptive use. We adjusted for potential confounding factors, including age, calendar year of diagnosis, education, smoking, alcohol, parity/age at first birth, and number of sexual partners. Among controls, 26% had used injectable and 20% had used oral contraceptives. For current and more recent users versus never users of oral or injectable contraceptives, the odds ratios (ORs) for breast cancer were significantly increased in users of oral and/or injectable contraceptives (OR 1.66, 95% CI 1.28-2.16, p<0.001) and separately among those exclusively using oral (1.57, 1.03-2.40, p = 0.04) and exclusively using injectable (OR 1.83, 1.31-2.55, p<0.001) contraceptives; corresponding ORs for cervical cancer were 1.38 (1.08-1.77, p = 0.01), 1.01 (0.66-1.56, p = 0.96), and 1.58 (1.16-2.15, p = 0.004). There was no significant increase in breast or cervical cancer risk among women ceasing hormonal contraceptive use ≥10 y previously (p = 0.3 and p = 0.9, respectively). For durations of use ≥5 y versus never use, the ORs of ovarian cancer were 0.60 (0.36-0.99, p = 0.04) for oral and/or injectable contraceptive use and 0.07 (0.01-0.49, p = 0.008) for injectable use exclusively; corresponding ORs for endometrial cancer were 0.44 (0.22-0.86, p = 0.02) and 0.36 (0.11-1.26, p = 0.1). CONCLUSIONS: In this study, use of oral and of injectable hormonal contraceptives was associated with a transiently increased risk of breast and cervical cancer and, for long durations of use, with a reduced risk of ovarian and endometrial cancer. The observed effects of injectable and of oral contraceptives on cancer risk in this study did not appear to differ substantially.


Subject(s)
Breast Neoplasms/epidemiology , Contraceptive Agents/adverse effects , Contraceptives, Oral/adverse effects , Endometrial Neoplasms/epidemiology , Ovarian Neoplasms/epidemiology , Uterine Cervical Neoplasms/epidemiology , Adolescent , Adult , Aged , Black People , Breast Neoplasms/chemically induced , Case-Control Studies , Endometrial Neoplasms/chemically induced , Female , Humans , Middle Aged , Ovarian Neoplasms/chemically induced , South Africa , Uterine Cervical Neoplasms/chemically induced , Young Adult
9.
J Natl Cancer Inst ; 104(2): 147-58, 2012 Jan 18.
Article in English | MEDLINE | ID: mdl-22228147

ABSTRACT

BACKGROUND: The role of human papillomavirus (HPV) in the causation of esophageal squamous cell carcinoma is unclear. We examined the associations between esophageal squamous cell carcinoma and 28 centrally measured HPV serological markers in serum from six existing case-control studies conducted in regions with differing background risks of esophageal cancer. METHODS: We used centralized multiplex serology to test serum samples from 1561 case subjects and 2502 control subjects from six case-control studies for antibodies to the major HPV capsid protein (L1) and/or the early proteins E6 and/or E7 of eight high-risk, two low-risk, and four cutaneous HPV types. Study-specific odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were estimated using conditional logistic regression with adjustment for smoking, alcohol consumption, and other potential confounders. Pooled odds ratios and 95% confidence intervals were calculated using either a linear mixed-effects approach or a joint fixed-effects approach. All statistical tests were two-sided. RESULTS: We found statistically significant associations between esophageal squamous cell carcinoma and antibodies to E6 for HPV16 (OR = 1.89, 95% CI = 1.09 to 3.29, P = .023) and HPV6 (OR = 2.53, 95% CI = 1.51 to 4.25, P < .001) but not for other tested HPV types. There were no statistically significant associations between esophageal squamous cell carcinoma and antibodies to E7 for any of the tested HPV types. Simultaneous seropositivity for HPV16 E6 and E7 was rare (four case subjects, two control subjects; OR = 5.57, 95% CI = 0.90 to 34.35; P = .064). We also found statistically significant associations between esophageal squamous cell carcinoma and capsid antibodies for the high-risk mucosal type HPV33 L1 (OR = 1.30, 95% CI = 1.00 to 1.69; P = .047) and the low-risk mucosal types HPV6 (OR = 1.22, 95% CI = 1.05 to 1.42; P = .010) and HPV11 (OR = 1.30, 95% CI = 1.09 to 1.56, P = .0036). CONCLUSIONS: We found limited serological evidence of an association between esophageal squamous cell carcinoma and HPV in the populations studied. Although HPV does not appear to be an important risk factor for esophageal squamous cell carcinoma, we cannot exclude the possibility that certain HPV types may be involved in a small subset of cancers.


Subject(s)
Alphapapillomavirus/immunology , Antibodies, Viral/blood , Carcinoma, Squamous Cell/virology , Esophageal Neoplasms/virology , Papillomavirus Infections/complications , Adult , Aged , Antigens, Viral/immunology , Case-Control Studies , Confidence Intervals , Confounding Factors, Epidemiologic , Female , Human papillomavirus 16/immunology , Human papillomavirus 18/immunology , Humans , Logistic Models , Male , Middle Aged , Odds Ratio , Papillomavirus Infections/diagnosis , Papillomavirus Infections/virology , Risk Assessment , Risk Factors , Sensitivity and Specificity , Tumor Virus Infections/complications
10.
Int J Cancer ; 122(10): 2260-5, 2008 May 15.
Article in English | MEDLINE | ID: mdl-18241034

ABSTRACT

The effect of the evolving HIV epidemic on cancer has been sparsely documented in Africa. We report results on the risk of cancer associated with HIV-1 infection using data from an ongoing study. A case-control analysis was used to estimate the relative risk (odds ratio, OR) of cancer types known to be AIDS defining: Kaposi's sarcoma (n = 333), non-Hodgkin lymphoma (NHL, n = 223) and cancers of the cervix (n = 1,586), and 11 cancer types possibly associated with HIV infection: Hodgkin lymphoma (n = 154), cancers of other anogenital organs (n = 157), squamous cell cancer of the skin (SCC, n = 70), oral cavity and pharynx (n = 319), liver (n = 83), stomach (n = 142), leukemia (n = 323), melanoma (n = 53), sarcomas other than Kaposi's (n = 93), myeloma (n = 189) and lung cancer (n = 363). The comparison group comprised 3,717 subjects with all other cancer types and 682 subjects with vascular disease. ORs were adjusted for age, sex (except cervical cancer), year of diagnosis, education and number of sexual partners. Significantly increased risks associated with HIV-1 infection were found for HIV/AIDS associated Kaposi's sarcoma (OR = 47.1, 95% CI = 31.9-69.8), NHL (OR = 5.9, 95% CI = 4.3-8.1) and cancer of the cervix (OR = 1.6, 95% CI = 1.3-2.0); Hodgkin's disease (OR = 1.6, 95% CI = 1.0-2.7), cancers of anogenital organs other than the cervix (OR = 2.2; 95% CI = 1.4-3.3) and SCC (OR = 2.6, 95% CI = 1.4-4.9) were also significantly increased. No significant associations were found between HIV and any of the other cancers examined. Risks for HIV-related cancers are consistent with previous studies in Africa, and are lower when compared to those observed in developed countries.


Subject(s)
Black People , HIV Infections/complications , HIV-1 , Neoplasms/epidemiology , Adolescent , Adult , Aged , Case-Control Studies , Female , Humans , Lymphoma, Non-Hodgkin/epidemiology , Lymphoma, Non-Hodgkin/etiology , Male , Middle Aged , Neoplasms/etiology , Neoplasms, Squamous Cell/epidemiology , Neoplasms, Squamous Cell/etiology , Sarcoma, Kaposi/epidemiology , Sarcoma, Kaposi/etiology , South Africa/epidemiology , Surveys and Questionnaires , Time Factors
11.
J Med Virol ; 79(9): 1370-4, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17607783

ABSTRACT

Human papillomavirus (HPV) types causing anogenital lesions and cancer are accepted as being sexually transmitted. The methods whereby children acquire these anogenital type HPV infections are unclear. The present study determined the prevalence of anti-HPV-16, HPV-11 and HPV-18 IgG antibodies in mothers and their children in an attempt to identify evidence of HPV transmission from mother to child. HPV virus-like particles (VLP) VLP-16, VLP-11 and VLP-18 were used in enzyme-linked immunosorbent assay to identify IgG antibodies in serum from 100 mothers and their 111 children. Antibodies to VLP-16, VLP-11 and VLP-18 were found in serum from 17%, 21% and 16% of mothers, respectively and seroprevalences were 9%, 11.7% and 9.9%, respectively amongst the children. Of the 111 children, 23 (20.7%) showed antibodies to one or more of the three HPV types tested. Seven of these (30.4%) HPV IgG positive children had the same antibodies to one or more HPV types as their mothers. The prevalence of HPV-11 was similar in children of seropositive compared with seronegative mothers (14% and 11%, respectively). The prevalence of HPV-16 and HPV-18 was higher in children of seropositive mothers compared with seronegative mothers (for HPV-16, 18% and 7%, respectively, P = 0.1, for HPV-18, 19% and 8%, respectively, P = 0.2). None of these differences were statistically significant indicating a lack of correlation between antibodies in mothers and children and no evidence to support vertical or horizontal mother to child transmission of HPV infection. Indications were of multiple sources of HPV infection in the children.


Subject(s)
Antibodies, Viral/blood , Capsid Proteins/immunology , Human papillomavirus 11/immunology , Human papillomavirus 16/immunology , Human papillomavirus 18/immunology , Papillomavirus Infections/epidemiology , Papillomavirus Infections/immunology , Adolescent , Adult , Antigens, Viral/immunology , Child , Child, Preschool , Female , Human papillomavirus 11/isolation & purification , Human papillomavirus 16/isolation & purification , Human papillomavirus 18/isolation & purification , Humans , Infant , Male , Middle Aged , Mothers , Papillomavirus Infections/virology , Seroepidemiologic Studies , South Africa/epidemiology
12.
Infect Agent Cancer ; 2: 6, 2007 Mar 02.
Article in English | MEDLINE | ID: mdl-17331260

ABSTRACT

BACKGROUND: Human papillomavirus type 16 (HPV-16) infection is an important cause of cervical cancer, other anogenital cancers and, possibly, some oral and pharyngeal cancers. The association of HPV-16 with oesophageal and with prostate cancers has not been firmly established. METHODS: We analysed sera from 3,757 HIV seronegative black South Africans using an anti-HPV IgG enzyme-linked immunosorbent assay (ELISA). The subjects were recruited from 1995 to 2000 as part of an ongoing cancer case control study. Cases were patients with newly diagnosed cancers of the cervix (n = 946), other anogenital organs (n = 80), the oral cavity and pharynx (n = 102), the oesophagus (n = 369) or the prostate (n = 205). The comparison group consisted of 2,055 age and sex-matched patients randomly selected from the same data base, diagnosed at the same hospitals, but with a vascular disease or with a cancer unrelated to HPV infection. Subjects' sera were randomly and blindly allocated onto ELISA plates. Optical density (OD) levels of anti-HPV-16 IgG of > 0.45 and > or = 0.767 were taken to be cut-offs for negative, medium and high antibody levels. RESULTS: After adjustment for potential confounders, cancer types that showed a statistically significant association with increased anti-HPV-16 IgG antibody (Ab) levels were cancer of the cervix (OR for medium Ab levels = 1.6, and for high = 2.4, p < 0.0001), cancers of other anogenital organs (OR for medium or high Ab levels = 2.5, p = 0.002), and cancer of the oesophagus (OR for medium Ab = 1.3, and high Ab levels = 1.6 p = 0.002). Cancers of the oral cavity and pharynx showed a borderline significant association in the unadjusted model (p = 0.05) but after adjustment for confounding the trend in relation to Ab levels was positive but not statistically significant (OR for medium Ab = 1.1, and high Ab = 1.5 p = 0.13). Prostate cancer was not associated with HPV-16 seropositivity (OR for medium Ab level = 1.4, and for high Ab level = 1.3, p = 0.3). CONCLUSION: If there is indeed an association between HPV-16 and oesophageal and possibly also some oral cavity and pharyngeal cancers, then emerging HPV vaccines may also reduce, at least in part, the incidence of these leading cancer types.

13.
BMC Infect Dis ; 3: 21, 2003 Sep 12.
Article in English | MEDLINE | ID: mdl-12971827

ABSTRACT

BACKGROUND: Infection with human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus (KSHV), is the necessary causal agent in the development of Kaposi's sarcoma (KS). Infection with HIV-1, male gender and older age all increase risk for KS. However, the geographic distribution of HHV-8 and KS both prior to the HIV/AIDS epidemic and with HIV/AIDS suggest the presence of an additional co-factor in the development of KS. METHODS: Between January 1994 and October 1997, we interviewed 2576 black in-patients with cancer in Johannesburg and Soweto, South Africa. Blood was tested for antibodies against HIV-1 and HHV-8 and the study was restricted to 2191 HIV-1 negative patients. Antibodies against the latent nuclear antigen of HHV-8 encoded by orf73 were detected with an indirect immunofluorescence assay. We examined the relationship between high anti-HHV-8 antibody titers (> or =1:51,200) and sociodemographic and behavioral factors using unconditional logistic regression models. Variables that were significant at p = 0.10 were included in multivariate analysis. RESULTS: Of the 2191 HIV-1 negative patients who did not have Kaposi's sarcoma, 854 (39.0%) were positive for antibodies against HHV-8 according to the immunofluorescent assay. Among those seropositive for HHV-8, 530 (62.1%) had low titers (1:200), 227 (26.6%) had medium titers (1:51,200) and 97 (11.4%) had highest titers (1:204,800). Among the 2191 HIV-1 negative patients, the prevalence of high anti-HHV-8 antibody titers (> or =1:51,200) was independently associated with increasing age (p-trend = 0.04), having a marital status of separated or divorced (p = 0.003), using wood, coal or charcoal as fuel for cooking 20 years ago instead of electricity (p = 0.02) and consuming traditional maize beer more than one time a week (p = 0.02; p-trend for increasing consumption = 0.05) although this may be due to chance given the large number of predictors considered in this analysis. CONCLUSIONS: Among HIV-negative subjects, patients with high anti-HHV-8 antibody titers are characterized by older age. Other associations that may be factors in the development of high anti-HHV-8 titers include exposure to poverty or a low socioeconomic status environment and consumption of traditional maize beer. The relationship between these variables and high anti-HHV-8 titers requires further, prospective study.


Subject(s)
Antibodies, Viral/blood , HIV-1/immunology , Herpesvirus 8, Human/immunology , Sarcoma, Kaposi/epidemiology , Adult , Age Distribution , Age Factors , Aged , Case-Control Studies , Female , HIV Seronegativity , Humans , Male , Middle Aged , Prevalence , Risk Factors , Sarcoma, Kaposi/immunology , Sarcoma, Kaposi/virology , South Africa
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