Cancer and HIV infection in Rwanda

Endemic Kaposi's Sarcoma

Kaposi's sarcoma (KS) is a common neoplasm in Eastern and central Africa reflecting the spread of human gammaherpesvirus-8 (HHV-8), now considered a necessary causal agent for the development of KS. The endemic KS subtype can follow an aggressive clinical course with ulcerative skin lesions with soft tissue invasion or even bone or visceral involvement. In the latter cases, a thorough imaging work-up and better follow-up schedules are warranted. As KS is a chronic disease, the therapeutic goal is to obtain sustainable remission in cutaneous and visceral lesions and a good quality of life. Watchful monitoring may be sufficient in localized cutaneous forms. Potential therapeutic modalities for symptomatic advanced KS include systemic chemotherapies, immunomodulators, immune checkpoint inhibitors, and antiangiogenic drugs.

Cancer in Africa 2018: The role of infections

We estimate the fractions of cancer attributed to infections in Africa in 2018. The number of new cancer cases occurring was taken from Globocan2018 with some additional estimations based on data from African population-based registries. Population attributable fractions were calculated using prevalence of infection and relative risk in exposed vs. nonexposed. The greatest share of infection-associated cancers is due to the human papillomaviruses (12.1% of all cancers in Africa and 15.4% in sub-Saharan Africa [SSA]); of these, cervical cancer is by far the most common. Kaposi sarcoma-associated herpesvirus is responsible for 3.1% of all cancers in Africa, the hepatitis viruses (B and C) for 2.9% and Helicobacter pylori for 2.7% (non-Cardia Gastric cancer and primary gastric lymphomas). Two percent of cancers are attributable to the Epstein-Barr virus, Schistosoma haematobium increases the risk of bladder cancer resulting in 1.0% of all cancers. HIV-related NHL and squamous cell carcinoma of the conjunctiva account for 0.6% of cancers. Altogether 24.5% of cancers in Africa and 28.7% in SSA are due to infectious agents. Infections are by far the most common cancer risk factor for cancer in Africa-the traditional risk factors (smoking, alcohol and unhealthy diet) probably cause only one in eight cancers in Africa. Prevention should focus on those infectious diseases preventable through vaccination (HPV and hepatitis B) which could reduce two-thirds of the burden. Helicobacter pylori and schistosomiasis are treatable with antibiotics and praziquantel, with a potential reduction of one in eight infection-associated cancers.

A case-control study of HIV infection and cancer in the era of antiretroviral therapy in Rwanda

The aim of this study was to assess the association between HIV infection and cancer risk in Rwanda approximately a decade after the introduction of antiretroviral therapy (cART). All persons seeking cancer care at Butaro Cancer Center of Excellence (BCCOE) in Rwanda from 2012 to 2016 were routinely screened for HIV, prior to being confirmed with or without cancer (cases and controls, respectively). Cases were coded according to ICD-O-3 and converted to ICD10. Associations between individual cancer types and HIV were estimated using adjusted unconditional logistic regression. 2,656 cases and 1,196 controls differed by gender (80.3% vs. 70.8% female), age (mean 45.5 vs. 37.7 years), place of residence and proportion of diagnoses made by histopathology (87.5% vs. 67.4%). After adjustment for these variables, HIV was significantly associated with Kaposi Sarcoma (n = 60; OR = 110.3, 95%CI 46.8-259.6), non-Hodgkin lymphoma (NHL) (n = 265; OR = 2.5, 1.4-4.6), Hodgkin lymphoma (HL) (n = 76; OR = 5.2, 2.3-11.6) and cancers of the cervix (n = 560; OR = 5.9, 3.8-9.2), vulva (n = 23; OR = 17.8, 6.3-50.1), penis (n = 29; OR = 8.3, 2.5-27.4) and eye (n = 17; OR = 4.7, 1.0-25.0). Associations varied by NHL/HL subtype, with that for NHL being limited to DLBCL (n = 56; OR = 6.6, 3.1-14.1), particularly plasmablastic lymphoma (n = 6, OR = 106, 12.1-921). No significant associations were seen with other commonly diagnosed cancers, including female breast cancer (n = 559), head and neck (n = 116) and colorectal cancer (n = 106). In conclusion, in the era of cART in Rwanda, HIV is associated with increased risk of a range of infection-related cancers, and accounts for an important fraction of cancers presenting to a referral hospital.

Evaluation for High-risk HPV in Squamous Cell Carcinomas and Precursor Lesions Arising in the Conjunctiva and Lacrimal Sac

High-risk human papilloma virus (HR-HPV) is a well-established causative agent of oropharyngeal squamous cell carcinoma (SCC). In addition, HR-HPV has occasionally been reported to be present in dysplastic and malignant lesions of the conjunctiva and lacrimal sac, although its overall incidence and etiological role in periocular SCC are controversial. Sequential surgical samples of 52 combined cases of invasive SCC (I-SCC) and SCC in situ (SCCIS) from 2 periocular sites (conjunctiva and lacrimal sac) diagnosed over a 14-year period (2000 to 2014) were selected for evaluation, and relevant patient characteristics were documented. p16 immunohistochemistry was performed as a screening test. All p16-positive cases were further evaluated for HR-HPV using DNA in situ hybridization (DNA ISH), and a subset was also analyzed by polymerase chain reaction (PCR). Of 43 ocular surface squamous neoplasias (OSSNs), 30% (n=13; 8 SCCIS and 5 I-SCC cases) were positive for HR-HPV. HPV-positive OSSNs occurred in 8 men and 5 women with a mean age of 60 years (range, 39 to 94 y). HPV type-16 was detected in all conjunctival cases evaluated by PCR. All 5 conjunctival I-SCCs were nonkeratinizing (n=4) or partially keratinizing (n=1) and managed by simple excision. In contrast, HPV-negative conjunctival I-SCCs were predominantly keratinizing (11 keratinizing and 2 nonkeratinizing). Of 9 lacrimal sac I-SCCs (LSSCCs), 66.7% (n=6) were positive for HR-HPV by p16 and DNA ISH; HPV subtypes were HPV-16 (n=5) and HPV-58 (n=1). In addition, 2 p16-positive cases with negative DNA ISH results were HR-HPV positive (HPV-16 and HPV-33) when evaluated by PCR, suggesting that the rate of HR-HPV positivity among the LSSCCs may be as high as 89% (n=8). The combined group of HR-HPV-positive LSSCCs was seen in 4 men and 4 women with a mean age of 60 years (range, 34 to 71 y). Seven of the 8 HPV-positive LSSCCs (87.5%) had a nonkeratinizing or partially keratinizing histomorphology, whereas 1 case (12.5%) was predominantly keratinizing. The presence of HR-HPV in 30% of OSSNs and at least 66.7% of LSSCCs suggests the possibility of an etiologic role for HR-HPV at these sites.

Kaposi Sarcoma among HIV Infected Patients in Lagos University Teaching Hospital, Nigeria: A 14-Year Retrospective Clinicopathological Study

Background. Despite the increased incidence of Kaposi sarcoma (KS) resulting from the Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS) pandemic, there is still significant underreporting of KS in this environment. Objectives. This study was aimed at determining the incidence and clinicopathologic patterns of KS among HIV infected patients in Lagos University Teaching Hospital (LUTH), Nigeria, over a 14-year period: January 2000 to December 2013. Methodology. The materials for this study included patients' hospital clinical files, duplicate copies of histopathologic reports, and tissue blocks and corresponding archival slides in the Anatomic and Molecular Pathology Department and the HIV/AIDS unit of the Department of Haematology. Results. Within the study period, 182 cases of KS were diagnosed, accounting for 1.2% of all patients managed for HIV/AIDS and 2.99% of solid malignant tumours. The male-to-female ratio and modal age group were 1 : 1.3 and 5th decade, respectively. Most cases (90%) had purely mucocutaneous involvement with the lower limb being the commonest site (65.8%). The majority of lesions were plaques (65.8%). Vascular formation was the predominant histologic type seen (43.5%). Conclusion. KS in Lagos followed the same epidemiologic trend as other centers in Nigeria, with an increasing incidence in this era of HIV/AIDS.

A review of the pattern of AIDS defining, HIV associated neoplasms and premalignant lesions diagnosed from 2000-2011 at Kenyatta National Hospital, Kenya

Background

Sub-Sahara Africa hosts up to 71 % of all HIV infected people in the world. With this high incidence of Human immunodeficiency virus ( HIV) comes the burden of co-morbidities such as malignant and premalignant lesions. Aids defining malignancies have been listed as Kaposi’s sarcoma, Non-Hodgkin’s lymphoma and invasive squamous cell carcinoma of the cervix. People with HIV/AIDS(PLWAS) have a higher risk of developing these neoplasms than the rest of the population. The pathogenesis of these neoplasms in people with HIV has been linked to immune suppression, persistent antigenic stimulation and cytokine dysregulation.

Current study analyzes and presents the patterns and trends in the presentation of HIV related malignancies in patients diagnosed through histopathology at Kenyatta National Hospital.

Aim

To describe the patterns of AIDS- defining and non-AIDS- defining malignancies and premalignant lesions 10 years pre- and post HAART period at Kenyatta National hospital, Kenya.

Methods and techniques

This was a hospital based descriptive cross sectional study. The Formalin fixed paraffin embedded (FFPE) blocks and histological reports of patients diagnosed between 2000 and 2011 were traced from archives. The patients’ demographic data and clinical presentation was entered in an excel spreadsheet and the diagnosis and coding confirmed by a histopathologist. The data was then cleaned and analyzed using SSPS version 17.0 Ink.

Results

A total of 173 lesions were reviewed and analyzed. Of these 118 (68 %) were from females and 55 from males (32 %). The male to female ratio was 1:2. The age range was from two to 56 years with a median of 36 years. Kaposi sarcoma is the leading AIDS defining malignancy in Kenya while invasive squamous cell carcinoma of the conjunctiva is the leading non-AIDS defining malignancy. This is closely followed by invasive squamous cell carcinoma of the cervix and NHL.

Conclusion

Kaposi sarcoma is the leading AIDS associated neoplasm in Kenya. Physicians and caretakers managing and following up on HIV/AIDS patients should look out for Kaposi sarcoma as a form of IRIS following the institution of HAART in all HIV/AIDS patients. The incidence of invasive squamous cell carcinoma of the conjunctiva is increasing in PLWAS in Kenya. There is therefore a need to introduce early screening programs for squamous intraepithelial neoplasm of the conjunctiva in HIV/AIDS patients.

Diagnostic accuracy of fine needle aspiration cytology in providing a diagnosis of cervical lymphadenopathy among HIV-infected patients

BACKGROUND

Opportunistic infections and malignancies cause lymphadenopathy in HIV-infected patients. The use and accuracy of fine needle aspiration cytology in diagnosing of cervical lymphadenopathy among HIV-infected patients is not well studied in Uganda.

OBJECTIVE

The aim of this study was to determine the diagnostic accuracy of fine needle aspiration cytology in providing a diagnosis of cervical lymphadenopathy among HIV-infected patients in Uganda.

METHODS

We consecutively recruited adult HIV-infected patients with cervical lymphadenopathy admitted to Mulago Hospital medical wards. Clinical examination, fine needle aspiration and lymph node biopsy were performed. We estimated the sensitivity, specificity; negative and positive predictive values using histology as the gold standard.

RESULTS

We enrolled 108 patients with a mean age of 33 years (range, 18-60), 59% were men and mean CD4 was 83(range, 22-375) cells/mm(3). The major causes of cervical lymphadenopathy were: tuberculosis (69.4%), Kaposi's sarcoma-KS (10.2%) and reactive adenitis (7.4%). Overall fine needle aspiration cytology accurately predicted the histological findings in 65 out of 73 cases (89%) and missed 7 cases (9.5%). With a sensitivity of 93.1%, specificity of 100%, positive predictive value of 100% and negative predictive value of 78.7% for tuberculosis and 80%; 98.4%;88.9% and 98.9% for KS respectively. No fine needle aspiration complications were noted.

CONCLUSIONS

Fine needle aspiration cytology is safe and accurate in the diagnosis of tuberculosis and KS cervical lymphadenopathy among HIV-positive patients.

The role of Kaposi sarcoma-associated herpesvirus in the pathogenesis of Kaposi sarcoma

Kaposi sarcoma (KS) is an unusual vascular tumour caused by an oncogenic-herpesvirus, Kaposi sarcoma-associated herpesvirus (KSHV), also known as human herpesvirus 8 (HHV 8). KS lesions are characterized by an abundant inflammatory infiltrate, the presence of KSHV-infected endothelial cells that show signs of aberrant differentiation, as well as faulty angiogenesis/ vascularization. Here we discuss the molecular mechanisms that lead to the development of these histological features of KS, with an emphasis on the viral proteins that are responsible for their development.

Co-infections, inflammation and oncogenesis: future directions for EBV research

Epstein-Barr virus (EBV) is aetiologically linked to a wide range of human tumours. Some arise as accidents of the virus' lifestyle in its natural niche, the B lymphoid system; these include B-lymphoproliferative disease of the immunocompromised, Hodgkin Lymphoma, Burkitt Lymphoma and particular forms of diffuse large B cell lymphoma. Interestingly, HIV infection increases the incidence of each of these B cell malignancies, though by different degrees and for different reasons. Other EBV-associated tumours arise through rare viral entry into unnatural target tissues; these include all cases of nasal T/NK cell lymphoma and of undifferentiated nasopharyngeal carcinoma plus a small but significant subset of gastric carcinomas, a tumour type more generally associated with chronic Helicobacter pylori infection. Understanding EBV's involvement in the pathogenesis of these different malignancies is an important long-term goal. This article focuses on two overlapping, but relatively neglected, areas of research that could contribute to that goal. The first addresses the mechanisms whereby coincident infections with other pathogens increase the risk of EBV-positive malignancies, and takes as its paradigm the actions of holoendemic malaria and HIV infections as co-factors in Burkitt lymphomagenesis. The second widens the argument to include both infectious and non-infectious sources of chronic inflammation in the pathogenesis of EBV-positive tumours such as T/NK cell lymphoma, nasopharyngeal carcinoma and gastric carcinoma.

Cancer burden among HIV-positive persons in Nigeria: preliminary findings from the Nigerian AIDS-cancer match study

BACKGROUND

Although Nigeria has a large HIV epidemic, the impact of HIV on cancer in Nigerians is unknown.

METHODS

We conducted a registry linkage study using a probabilistic matching algorithm among a cohort of HIV positive persons registered at health facilities where the Institute of Human Virology Nigeria (IHVN) provides HIV prevention and treatment services. Their data was linked to data from 2009 to 2012 in the Abuja Cancer Registry. Match compatible files with first name, last name, sex, date of birth and unique HIV cohort identification numbers were provided by each registry and used for the linkage analysis. We describe demographic characteristics of the HIV clients and compute Standardized Incidence Ratios (SIRs) to evaluate the association of various cancers with HIV infection.

RESULTS

Between 2005 and 2012, 17,826 persons living with HIV (PLWA) were registered at IHVN. Their median age (Interquartile range (IQR)) was 33 (27-40) years; 41% (7246/17826) were men and 59% (10580/17826) were women. From 2009 to 2012, 2,029 clients with invasive cancers were registered at the Abuja Cancer Registry. The median age (IQR) of the cancer clients was 45 (35-68) years. Among PLWA, 39 cancer cases were identified, 69% (27/39) were incident cancers and 31% (12/39) were prevalent cancers. The SIR (95% CI) for the AIDS Defining Cancers were 5.7 (4.1, 7.2) and 2.0 (0.4, 3.5), for Kaposi Sarcoma and Cervical Cancer respectively.

CONCLUSION

The risk of Kaposi Sarcoma but not Cervical Cancer or Non-Hodgkin's Lymphoma, was significantly increased among HIV positive persons, compared to the general population in Nigeria.

HIV and HPV infections and ocular surface squamous neoplasia: systematic review and meta-analysis

BACKGROUND

The frequency of ocular surface squamous neoplasias (OSSNs) has been increasing in populations with a high prevalence of infection with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) and infection with human papillomavirus (HPV). We aimed to quantify the association between HIV/AIDS and HPV infection and OSSN, through systematic review and meta-analysis.

METHODS

The articles providing data on the association between HIV/AIDS and/or HPV infection and OSSN were identified in MEDLINE, SCOPUS and EMBASE searched up to May 2013, and through backward citation tracking. The DerSimonian and Laird method was used to compute summary relative risk (RR) estimates and 95% confidence intervals (95% CI). Heterogeneity was quantified with the I(2) statistic.

RESULTS

HIV/AIDS was strongly associated with an increased risk of OSSN (summary RR=8.06, 95% CI: 5.29-12.30, I(2)=56.0%, 12 studies). The summary RR estimate for the infection with mucosal HPV subtypes was 3.13 (95% CI: 1.72-5.71, I(2)=45.6%, 16 studies). Four studies addressed the association between both cutaneous and mucosal HPV subtypes and OSSN; the summary RR estimates were 3.52 (95% CI: 1.23-10.08, I(2)=21.8%) and 1.08 (95% CI: 0.57-2.05, I(2)=0.0%), respectively.

CONCLUSION

Human immunodeficiency virus infection increases the risk of OSSN by nearly eight-fold. Regarding HPV infection, only the cutaneous subtypes seem to be a risk factor.

Relationship between non-Hodgkin's lymphoma and blood levels of Epstein-Barr virus in children in north-western Tanzania: a case control study

Background

Non-Hodgkin’s Lymphomas (NHL) are common in African children, with endemic Burkitt’s lymphoma (BL) being the most common subtype. While the role of Epstein-Barr Virus (EBV) in endemic BL is known, no data are available about clinical presentations of NHL subtypes and their relationship to Human Immunodeficiency Virus (HIV) infection and Epstein Barr Virus (EBV) load in peripheral blood of children in north-western, Tanzania.

Methods

A matched case control study of NHL subtypes was performed in children under 15 years of age and their respective controls admitted to Bugando Medical Centre, Sengerema and Shirati district designated hospitals in north-western, Tanzania, between September 2010 and April 2011. Peripheral blood samples were collected on Whatman 903 filter papers and EBV DNA levels were estimated by multiplex real-time PCR. Clinical and laboratory data were collected using a structured data collection tool and analysed using chi-square, Fisher and Wilcoxon rank sum tests where appropriate. The association between NHL and detection of EBV in peripheral blood was assessed using conditional logistic regression model and presented as odds ratios (OR) and 95% confidence intervals (CI).

Results

A total of 35 NHL cases and 70 controls matched for age and sex were enrolled. Of NHLs, 32 had BL with equal distribution between jaw and abdominal tumour, 2 had large B cell lymphoma (DLBCL) and 1 had NHL-not otherwise specified (NHL-NOS). Central nervous system (CNS) presentation occurred only in 1 BL patient; 19 NHLs had stage I and II of disease. Only 1 NHL was found to be HIV-seropositive. Twenty-one of 35 (60%) NHL and 21 of 70 (30%) controls had detectable EBV in peripheral blood (OR = 4.77, 95% CI 1.71 – 13.33, p = 0.003). In addition, levels of EBV in blood were significantly higher in NHL cases than in controls (p = 0.024).

Conclusions

BL is the most common childhood NHL subtype in north-western Tanzania. NHLs are not associated with HIV infection, but are strongly associated with EBV load in peripheral blood. The findings suggest that high levels of EBV in blood might have diagnostic and prognostic relevance in African children.

Cancer in the Sudan: an overview of the current status of knowledge on tumor patterns and risk factors

The Sudan, the largest and most diverse country in Africa, is experiencing a growing cancer problem, but little is presently known on tumor patterns, cancer epidemiology and ethnic or environmental cancer risk factors. We review here the current status of knowledge, summarizing data from local and international publications as well as primary information from the only two cancer hospitals of the country, both located in Central Sudan (Khartoum and Wad Medani). We provide frequencies reported for cancers detected in adults and children, and summarize studies on specific cancer types, as well as information on risk factors that most likely impact on tumor patterns.

Prevalence and Risk Factors Associated with Precancerous Cervical Cancer Lesions among HIV-Infected Women in Resource-Limited Settings

Objective. To assess the prevalence and identified associated risk factors for precancerous cervical cancer lesions among HIV-infected women in resource-limited settings in Kenya. Methods. HIV-infected women attending the ART clinic at the Nazareth Hospital ART clinic between June 2009 and September 2010. Multivariate logistic regression model with odds ratios and 95% confidence intervals (CI) were estimated after controlling for important covariates. Result. A total of 715 women were screened for cervical cancer. The median age of the participants was 40 years (range 18-69 years). The prevalence of precancerous lesions (CINI, CINII, CIN III, ICC) was 191 (26.7%). After controlling for other variables in logistic regression analysis, cervical precancerous lesions were associated with not being on ART therapy; whereby non-ART were 2.21 times more likely to have precancerous lesions than ART patients [(aOR) = 2.21, 95% CI (1.28-3.83)]. Conclusion. The prevalence of precancerous cervical lesions was lower than other similar settings. It is recommended that cancer screening of HIV-infected women should be an established practice. Availability and accessibility of these services can be done through their integration into HIV. Prompt initiation of HAART through an early enrollment into care has an impact on reducing the prevalence and progression of cervical precancerous lesions.

HIV and cancer in Africa: mutual collaboration between HIV and cancer programs may provide timely research and public health data

The eruption of Kaposi sarcoma (KS) and aggressive non-Hodgkin lymphoma (NHL) in young homosexual men in 1981 in the West heralded the onset of the human immunodeficiency virus (HIV) infection epidemic, which remains one of the biggest challenges to global public health and science ever. Because KS and NHL were increased >10,000 and 50-600 times, respectively, with HIV, they were designated AIDS defining cancers (ADC). Cervical cancer (CC), increased 5-10 times was also designated as an ADC. A few other cancers are elevated with HIV, including Hodgkin lymphoma (10 times), anal cancer (15-30 times), and lung cancer (4 times) are designated as non-AIDS defining cancers (NADCs). Since 1996 when combination antiretroviral therapy (cART) became widely available in the West, dramatic decreases in HIV mortality have been observed and substantial decrease in the incidence of ADCs. Coincidentally, the burden of NADCs has increased as people with HIV age with chronic HIV infection. The impact of HIV infection on cancer in sub-Saharan Africa, where two thirds of the epidemic is concentrated, remains poorly understood. The few studies conducted indicate that risks for ADCs are also increased, but quantitatively less so than in the West. The risks for many cancers with established viral associations, including liver and nasopharynx, which are found in Africa, do not appear to be increased. These data are limited because of competing mortality, and cancer is under diagnosed, pathological confirmation is rare, and cancer registration not widely practiced. The expansion of access to life-extending cART in sub-Saharan Africa, through programs such as the Global Fund for AIDS, Malaria, and Tuberculosis and the US President's Emergency Program for AIDS Relief (PEPFAR), is leading to dramatic lengthening of life of HIV patients, which will likely influence the spectrum and burden of cancer in patients with HIV. In this paper, we review current literature and explore merits for integrating cancer research in established HIV programs to obtain timely data about the incidence and burden of cancer in HIV-infected persons in Africa.

Impact of infection with human immunodeficiency virus-1 (HIV) on the risk of cancer among children in Malawi - preliminary findings

BACKGROUND

The impact of infection with HIV on the risk of cancer in children is uncertain, particularly for those living in sub-Saharan Africa. In an ongoing study in a paediatric oncology centre in Malawi, children (aged

METHODS

Only children with a cancer diagnosis were included. Odds ratios (OR) for being HIV positive were estimated for each cancer type (with adjustment for age (<5 years, >/= 5 years) and sex) using children with other cancers and non-malignant conditions as a comparison group (excluding the known HIV-associated cancers, Kaposi sarcoma and lymphomas, as well as children with other haematological malignancies or with confirmed non-cancer diagnoses).

RESULTS

Of the 586 children recruited, 541 (92%) met the inclusion criteria and 525 (97%) were tested for HIV. Overall HIV seroprevalence was 10%. Infection with HIV was associated with Kaposi sarcoma (29 cases; OR = 93.5, 95% CI 26.9 to 324.4) and with non-Burkitt, non-Hodgkin lymphoma (33 cases; OR = 4.4, 95% CI 1.1 to 17.9) but not with Burkitt lymphoma (269 cases; OR = 2.2, 95% CI 0.8 to 6.4).

CONCLUSIONS

In this study, only Kaposi sarcoma and non-Burkitt, non-Hodgkin lymphoma were associated with HIV infection. The endemic form of Burkitt lymphoma, which is relatively frequent in Malawi, was not significantly associated with HIV. While the relatively small numbers of children with other cancers, together with possible limitations of diagnostic testing may limit our conclusions, the findings may suggest differences in the pathogenesis of HIV-related malignancies in different parts of the world.

Collapse

Key Words Collapse

MESH Headings Collapse

Grants Collapse

Affiliation(s)

Nora Mutalima Epidemiology and Genetics Unit, Department of Health Sciences, Seebohm Rowntree Building, Area 3, University of York, York YO10 5DD, UK
Elizabeth M Molyneux Department of Paediatrics, University of Malawi, College of Medicine, P/Bag 360 Chichiri, Blantyre 3, Malawi
William T Johnston Epidemiology and Genetics Unit, Department of Health Sciences, Seebohm Rowntree Building, Area 3, University of York, York YO10 5DD, UK
Harold W Jaffe Department of Public Health, University of Oxford, Rosemary Rue Building, Old Road Campus, Roosevelt Drive, Headington, Oxford OX3 7LF, UK
Steve Kamiza Department of Histopathology, University of Malawi, College of Medicine, P/Bag 360 Chichiri, Blantyre 3, Malawi
Eric Borgstein Department of Surgery, University of Malawi, College of Medicine, P/Bag 360 Chichiri, Blantyre 3, Malawi
Nyengo Mkandawire Department of Surgery, University of Malawi, College of Medicine, P/Bag 360 Chichiri, Blantyre 3, Malawi
George N Liomba Department of Histopathology, University of Malawi, College of Medicine, P/Bag 360 Chichiri, Blantyre 3, Malawi
Mkume Batumba Department of Ophthalmology, University of Malawi, College of Medicine, P/Bag 360 Chichiri, Blantyre 3, Malawi
Lucy M Carpenter Department of Public Health, University of Oxford, Rosemary Rue Building, Old Road Campus, Roosevelt Drive, Headington, Oxford OX3 7LF, UK
Robert Newton Epidemiology and Genetics Unit, Department of Health Sciences, Seebohm Rowntree Building, Area 3, University of York, York YO10 5DD, UK

Collapse

The challenge of AIDS-related malignancies in sub-Saharan Africa

BACKGROUND

With the lengthening of life expectancy among HIV-positive subjects related to the use of highly active antiretroviral treatments, an increased risk of cancer has been described in industrialized countries. The question is to determine what occurs now and will happen in the future in the low income countries and particularly in sub-Saharan Africa where more than two-thirds of all HIV-positive people live in the world. The objective of our paper is to review the link between HIV and cancer in sub-Saharan Africa, putting it in perspective with what is already known in Western countries.

METHODS AND FINDINGS

Studies for this review were identified from several bibliographical databases including Pubmed, Scopus, Cochrane, Pascal, Web of Science and using keywords "HIV, neoplasia, epidemiology and Africa" and related MesH terms. A clear association was found between HIV infection and AIDS-classifying cancers. In case-referent studies, odds ratios (OR) were ranging from 21.9 (95% Confidence Interval (CI) 12.5-38.6) to 47.1 (31.9-69.8) for Kaposi sarcoma and from 5.0 (2.7-9.5) to 12.6 (2.2-54.4) for non Hodgkin lymphoma. The association was less strong for invasive cervical cancer with ORs ranging from 1.1 (0.7-1.2) to 1.6 (1.1-2.3), whereas ORs for squamous intraepithelial lesions were higher, from 4.4 (2.3-8.4) to 17.0 (2.2-134.1). For non AIDS-classifying cancers, squamous cell conjunctival carcinoma of the eye was associated with HIV in many case-referent studies with ORs from 2.6 (1.4-4.9) to 13.0 (4.5-39.4). A record-linkage study conducted in Uganda showed an association between Hodgkin lymphoma and HIV infection with a standardized incidence ratio of 5.7 (1.2-17) although OR in case-referent studies ranged from 1.4 (0.7-2.8) to 1.6 (1.0-2.7). Other cancer sites found positively associated with HIV include lung, liver, anus, penis, vulva, kidney, thyroid and uterus and a decreased risk of female breast cancer. These results so far based on a relatively small number of studies warrant further epidemiological investigations, taking into account other known risk factors for these tumors.

CONCLUSION

Studies conducted in sub-Saharan Africa show that HIV infection is not only strongly associated with AIDS-classifying cancers but also provided some evidence of association for other neoplasia. African countries need now to implement well designed population-based studies in order to better describe the spectrum of AIDS-associated malignancies and the most effective strategies for their prevention, screening and treatment.

Audit of gynaecological cancers Queen Elizabeth Central Hospital, Blantyre

The aim of the audit was to assess the trend of the gynaecological cancers for the first quarter of 2008, and the prevalence of HIV and syphilis among the cases. Gynaecological cancer cases accounted for 6% of gynaecological admissions at QECH between January and April 2008. The findings show that cervical cancer still remains the leading gynaecological cancer among women in the unit. Among the cases where HIV testing was done, 50% of cases tested HIV positive and these were all cervical, vaginal and vulval cancer cases. Syphilis was prevalent in 10% of the cases. Low socioeconomic status and young age was associated with cervical cancer. A majority of the cases of advanced cervical cancer had been sub optimally managed by health workers at initial visit when the disease was at its early stage hence missing an opportunity for adequate treatment.

Burkitt's lymphoma in Africa, a review of the epidemiology and etiology

Burkitt's lymphoma (BL) was first described in Eastern Africa, initially thought to be a sarcoma of the jaw. Shortly it became well known that this was a distinct form of Non Hodgkin's lymphoma. The disease has given insight in all aspects of cancer research and care. Its peculiar epidemiology has led to the discovery of Epstein Barr virus (EBV) and its importance in the cause of several viral illnesses and malignancies. The highest incidence and mortality rates of BL are seen in Eastern Africa. BL affects mainly children, and boys are more susceptible than girls. Evidence for a causal relationship between EBV and BL in the endemic form is fairly strong. Frequency of association between EBV and BL varies between different patient groups and different parts of the world. EBV may play a role in the pathogenesis of BL by deregulation of the oncogene c-MYC by chromosomal translocation. Although several studies suggest an association between malaria and BL, there has never been a conclusive population study in support of a direct role of malaria in causation of BL. The emergence of HIV and a distinct subtype of BL in HIV infected have brought a new dimension to the disease particularly in areas where both HIV and BL are endemic. BL has been reported as a common neoplasmin HIV infected patients, but not in other forms of immuno-depression, and the occurrence of BL seems to be higher amongst HIV positive adults, while the evidence of an association amongst children is still disputed. The role of other possible risk factors such as low socio-economical status, exposure to a plant species common in Africa called Euphorbiaceae, exposure to pesticies and to other infections such as schistosomiasis and arbovirus (an RNA virus transmitted by insect vectors) remain to be elucidated.

The spectrum of human immunodeficiency virus-associated cancers in a South African black population: results from a case-control study, 1995-2004

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.

AIDS malignancies

Among individuals with HIV-infection, coinfection with oncogenic viruses including EBV, HHV-8, and HPV cause significant cancer-related morbidity and mortality. It is clear that these viruses interact with HIV in unique ways that predispose HIV-infected individuals to malignant diseases. In general, treatment directed specifically against these viruses does not appear to change the natural history of the malignant disease, and once the malignancy develops, if their health permits, HIV-infected patients should be treated using similar treatment protocols to HIV-negative patients. However, for the less frequent HIV-related malignancies, such as PEL, or MCD, optimal treatments are still emerging. For certain AIDS-defining malignancies, it is clear that the widespread access to HAART has significantly decreased the incidence, and improved outcomes. However, for other cancers, such as the HPV-related tumors, the role of HAART is much less clear. Further research into prevention and treatment of these oncogenic virally mediated AIDS-related malignancies is necessary.

The global health burden of infection-associated cancers in the year 2002

Several infectious agents are considered to be causes of cancer in humans. The fraction of the different types of cancer, and of all cancers worldwide and in different regions, has been estimated using several methods; primarily by reviewing the evidence for the strength of the association (relative risk) and the prevalence of infection in different world areas. The estimated total of infection-attributable cancer in the year 2002 is 1.9 million cases, or 17.8% of the global cancer burden. The principal agents are the bacterium Helicobacter pylori (5.5% of all cancer), the human papilloma viruses (5.2%), the hepatitis B and C viruses (4.9%), Epstein-Barr virus (1%), human immunodeficiency virus (HIV) together with the human herpes virus 8 (0.9%). Relatively less important causes of cancer are the schistosomes (0.1%), human T-cell lymphotropic virus type I (0.03%) and the liver flukes (0.02%). There would be 26.3% fewer cancers in developing countries (1.5 million cases per year) and 7.7% in developed countries (390,000 cases) if these infectious diseases were prevented. The attributable fraction at the specific sites varies from 100% of cervix cancers attributable to the papilloma viruses to a tiny proportion (0.4%) of liver cancers (worldwide) caused by liver flukes.

Spectrum of cancers among HIV-infected persons in Africa: The Uganda AIDS-Cancer Registry Match Study

Although more than 25 million people in sub-Saharan Africa have human immunodeficiency virus (HIV) infection, little is known regarding their cancer risk. We investigated cancer risk among persons with HIV/AIDS in Uganda using record-linkage. We linked records of 12,607 HIV-infected persons attending The AIDS Support Organization (TASO) in Kyadondo County from October 1988 through December 2002 to the Kampala Cancer Registry. We calculated standardized incidence ratios (SIRs) to identify increased cancer risks in the early (4-27 months after TASO registration), late (28-60 months), or combined (4-60 months) incidence periods. We identified 378 cancers (181 prevalent, 197 incident) among TASO participants. Of incident cancers, 137 (70%) were AIDS-defining cancers. Risk was increased in the early-incident period, compared to the general population, for the AIDS-defining cancers: Kaposi sarcoma (SIR 6.4, 95%CI 4.8-8.4), non-Hodgkin lymphoma (6.7, 1.8-17), and cervical carcinoma (2.4, 1.1-4.4). These three cancers were also increased in the combined periods. Risks of five non-AIDS-defining cancers were increased in the combined periods: Hodgkin lymphoma (5.7, 1.2-17) and cancers of the conjunctiva (SIR 4.0; 1.5-8.7), kidney (16, 1.8-58), thyroid (5.7, 1.1-16), and uterus (5.5, 1.5-14). Cancers of the breast, nasopharynx, and lung were increased either in the early or late incident periods only. Among 407 children, seven cancers were observed, of which five were Kaposi sarcoma. The application of a record-linkage design in Africa broadens the repertoire of epidemiological tools for studying HIV-infected populations. We confirm the increased risks of AIDS-defining cancers and report increased risks of a few non-AIDS-defining cancers.

AIDS-associated cancer in developing nations

PURPOSE OF REVIEW

With the emergence of the highly active antiretroviral therapy era, it is apparent that the incidence of Kaposi sarcoma, in particular, and lymphoma in patients with AIDS is declining, especially in regions of the world where these regimens are routinely available. The burden of HIV infection and AIDS is greatest in the developing world, and no doubt neoplastic complications are increasingly encountered. The purpose of this review is to highlight recent developments of this aspect of the AIDS epidemic in the developing world.

RECENT FINDINGS

It was readily apparent that the incidence of Kaposi sarcoma sharply increased after the onset of the AIDS epidemic in developing countries. By the end of the second decade of the epidemic, non-Hodgkin lymphoma is increasing in incidence and the natural history of Burkitt lymphoma is evolving in the backdrop of HIV infection as well. Cervical cancer is the most common cancer in women in many developing countries, yet the true impact of HIV infection on the development of this neoplasm is not fully understood. Squamous cell carcinoma of the conjunctiva appears to be a unique AIDS-associated neoplasm that is encountered in sub-Saharan Africa as well. Finally, although the epidemiologic and clinicopathologic features for many AIDS-associated neoplasms are well characterized in developing regions of the world, there is a paucity of data on the therapeutic approach to these tumors in this setting.

SUMMARY

It is apparent that as the AIDS pandemic proceeds, the burden of neoplastic diseases is increasing in developing nations. Current therapeutic approaches are not well documented. Pragmatic prevention and therapeutic interventions suitable for the resource-constrained setting are clearly needed.

Estimating HIV prevalence and the impact of HIV/AIDS on a Ugandan hospital by combining serosurvey data and hospital discharge records

OBJECTIVE

To estimate the disease-specific HIV prevalence in a northern Ugandan hospital and to evaluate the impact of HIV/AIDS on hospital services.

DESIGN

HIV serosurvey and analysis of routinely compiled hospital records.

METHODS

The serosurvey was conducted among all 352 patients admitted to the medical ward of the Lacor Hospital in March 1999 (this ward consists of 3 units: general medicine, tuberculosis, and cancer). The impact on hospital services was estimated using the hospital discharge records for all 3447 patients admitted in 1999, in combination with serosurvey data, and was expressed as the percentage of bed-days attributable to HIV-positive patients.

RESULTS

The overall HIV prevalence was 42.0% (52.6, 44.6, and 13.2% in the general medicine, tuberculosis, and cancer units, respectively). The disease-specific prevalence ranged from 45-65% for patients with tuberculosis, pneumonia, malaria, and enteritis. HIV-positive patients, compared with HIV-negative patients, had a higher in-hospital mortality (14.6 vs. 3.0%) and a lower average length of stay (41.4 vs. 48.9 days). AIDS cases accounted for 5.0% of hospital admissions, 4.1% of bed-days, and 11.5% of deaths. When considering all HIV-positive patients, these accounted for 37.2% of the bed-days.

CONCLUSIONS

Knowledge of disease-specific HIV prevalence and of the patterns of HIV-related diseases is crucial for early case management. The impact of HIV-positive patients on hospital services is quite high, accounting for >1/3 of the bed-days in 1999. Providing a continuum of care through inpatient, outpatient, and outreach home care services probably represents the only means of relieving the pressure on overloaded hospitals.

Epidemiology of AIDS-related malignancies an international perspective

Patients with HIV infection are at increased risk for developing Kaposi's sarcoma, non-Hodgkin's lymphoma, and several other cancers. The relative risks for the most common epithelial cancers in the general population--lung, breast, colon/rectum, stomach, liver, and prostate--are not increased substantially in people with AIDS, however. Accumulating data suggest that HIV-infected patients also are at increased risk for developing Hodgkin's lymphoma, cervical carcinoma in situ (CIS), other anogenital neoplasms (invasive cancer and CIS), leiomyosarcoma, and conjunctival squamous cell carcinoma. There is inconclusive evidence, however, with regard to HIV infection being associated with invasive cervical cancer, testicular seminoma, or hepatocellular carcinoma. Notably, other viral infections have been implicated in the etiology of many of these conditions. The introduction of highly active antiretroviral therapy (HAART) has decreased the incidence of AIDS-associated cancers in Western countries, but less than 1% of AIDS patients are receiving HAART in the HIV epicenter of sub-Saharan Africa. Further therapeutic advances that extend survival with HIV infection with varying reconstitution of immune competence may lead to additional alterations in cancer risk.

Epidemiology of non-Hodgkin lymphomas and other haemolymphopoietic neoplasms in people with AIDS

HIV-infected individuals have a high risk of developing non-Hodgkin lymphoma (NHL). In Europe, the prevalence of AIDS with a concurrent NHL diagnosis increased from 3.6% to 5.4% between 1994 and 2000. In population-based record linkages between cancer registries and AIDS registries in the USA, Italy, and Australia, the relative risks of NHL in people with AIDS ranged between 15 for low-grade and T-cell NHL and 400 for high-grade NHL. The corresponding relative risk of Hodgkin's disease was about 10, whereas the risks for multiple myeloma and leukaemias were in the range 2 to 5. Since the introduction of highly active antiretroviral therapy in the more developed countries (1996), most studies have suggested a decline in the incidence of some types of NHL, most notably the primary brain form. In studies from Africa, the risk of HIV-associated NHL is about ten times less than that in the more developed countries, but underascertainment and earlier death from other AIDS-related illnesses may explain the relative lack of HIV-associated lymphomas.

Global and regional estimates of cancer mortality and incidence by site: I. Application of regional cancer survival model to estimate cancer mortality distribution by site

BACKGROUND

The Global Burden of Disease 2000 (GBD 2000) study starts from an analysis of the overall mortality envelope in order to ensure that the cause-specific estimates add to the total all cause mortality by age and sex. For regions where information on the distribution of cancer deaths is not available, a site-specific survival model was developed to estimate the distribution of cancer deaths by site.

METHODS

An age-period-cohort model of cancer survival was developed based on data from the Surveillance, Epidemiology, and End Results (SEER). The model was further adjusted for the level of economic development in each region. Combined with the available incidence data, cancer death distributions were estimated and the model estimates were validated against vital registration data from regions other than the United States.

RESULTS

Comparison with cancer mortality distribution from vital registration confirmed the validity of this approach. The model also yielded the cancer mortality distribution which is consistent with the estimates based on regional cancer registries. There was a significant variation in relative interval survival across regions, in particular for cancers of bladder, breast, melanoma of the skin, prostate and haematological malignancies. Moderate variations were observed among cancers of colon, rectum, and uterus. Cancers with very poor prognosis such as liver, lung, and pancreas cancers showed very small variations across the regions.

CONCLUSIONS

The survival model presented here offers a new approach to the calculation of the distribution of deaths for areas where mortality data are either scarce or unavailable.

The epidemiology of conjunctival squamous cell carcinoma in Uganda

As part of a larger investigation of cancer in Uganda, we conducted a case-control study of conjunctival squamous cell carcinoma in adults presenting at hospitals in Kampala. Participants were interviewed about social and lifestyle factors and had blood tested for antibodies to HIV, KSHV and HPV-16, -18 and -45. The odds of each factor among 60 people with conjunctival cancer was compared to that among 1214 controls with other cancer sites or types, using odds ratios, estimated with unconditional logistic regression. Conjunctival cancer was associated with HIV infection (OR 10.1, 95% confidence intervals [CI] 5.2-19.4; P<0.001), and was less common in those with a higher personal income (OR=0.4, 95% CI 0.3-0.7; P<0.001)[corrected]. The risk of conjunctival cancer increased with increasing time spent in cultivation and therefore in direct sunlight (chi2 trend=3.9, P=0.05), but decreased with decreasing age at leaving home (chi2 trend=3.9, P=0.05), perhaps reflecting less exposure to sunlight consequent to working in towns, although both results were of borderline statistical significance. To reduce confounding, sexual and reproductive variables were examined among HIV seropositive individuals only. Cases were more likely than controls to report that they had given or received gifts for sex (OR 3.5, 95% CI 1.2-10.4; P=0.03), but this may have been a chance finding as no other sexual or reproductive variable was associated with conjunctival cancer, including the number of self-reported lifetime sexual partners (P=0.4). The seroprevalence of antibodies against HPV-18 and -45 was too low to make reliable conclusions. The presence of anti-HPV-16 antibodies was not significantly associated with squamous cell carcinoma of the conjunctiva (OR 1.5, 95% CI 0.5-4.3; P=0.5) and nor were anti-KSHV antibodies (OR 0.9, 95% CI 0.4-2.1; P=0.8). The 10-fold increased risk of conjunctival cancer in HIV infected individuals is similar to results from other studies. The role of other oncogenic viral infections is unclear.

Pathology of the breast associated with HIV/AIDS

Breast pathology that is characteristic of patients infected with human immunodeficiency virus (HIV) has not been addressed in the literature. HIV may directly and indirectly affect the glandular, mesenchymal, and intramammary lymphoid tissue in seropositive patients. Likely infections in this setting include tuberculous mastitis and pyogenic abscesses that may lead to fatal septicemia. Benign stromal changes include gynecomastia, adipose tissue deposition as part of the fat maldistribution syndrome, and pseudoangiomatous stromal hyperplasia. Breast carcinoma in HIV-infected patients occurs at a relatively early age, with increased bilateral disease, unusual histology, and early metastatic spread with a poor outcome. However, the link between breast cancer and HIV remains controversial. Kaposi's sarcoma and non-Hodgkin's lymphoma may also be localized to the breast in patients with acquired immunodeficiency syndrome (AIDS). This article reviews benign and malignant breast diseases that are likely to be encountered in patients with HIV/AIDS.

The interrelation of HIV, cervical human papillomavirus, and neoplasia among antenatal clinic attenders in Tanzania

OBJECTIVES

To determine the prevalence and interrelation of cervical human papillomavirus (HPV) genotypes, squamous intraepithelial lesions (SIL), HIV, and other reproductive tract infections (RTIs) among urban antenatal clinic attenders in Mwanza, Tanzania.

METHODS

Genital swabs were collected from 660 pregnant women and tested for a range of RTIs and for cervical cytology. Cervical HPV-DNA was detected by PCR and genotyped. HIV and syphilis serologies were performed.

RESULTS

HPV prevalence was 34% (209/612 women). Of the 144 typeable samples, 83% were high risk (HR-HPV) oncogenic strains (56% HPV 16 related types). SIL was detected in 43 women (7%), with high grade SIL in 3%. There was a high prevalence of HIV (15%), and of any RTI (83%). Genital warts were detected in 20 women (3%). HPV infection was associated with some behavioural factors (short duration of relationship, single status, not using condoms) and gonorrhoea. There was no overall association between HPV and HIV (OR=1.02, 95% CI 0.6-1.6), but a non-significant trend towards a stronger association with HR-HPV in women aged 15-19 (OR=2.79, 95% CI 0.8-9.5) and women aged > or =30 (OR=3.20, 95% CI 0.7-15). SIL was associated with HPV (OR=3.66, 95% CI 1.9-7.0), but not significantly with HIV (OR=1.54, 95% CI 0.7-3.4). Prevalence of SIL was higher among women dually positive for HPV/HIV compared to HPV infection only (21% v 12%), although this difference was not statistically significant (p=0.17).

CONCLUSIONS

HPV infection was highly prevalent in this young antenatal population. The association of HIV with HR-HPV types in older women may suggest that the principal HIV/HPV interaction in this population is for HIV to upregulate HPV persistence, leading to subsequent development of SIL.

Epidemiology of AIDS-related tumours in developed and developing countries

AIDS-associated illnesses include Kaposi's sarcoma (KS), non-Hodgkin's lymphoma (NHL), and, since 1993, invasive cervical cancer (ICC). Between 1988 and 1998, among AIDS cases reported in western Europe, 9.6% had KS and 3.9% had NHL as AIDS-defining illnesses. Between 1988 and 1998, the frequency of KS decreased from 13.4 to 6.4%, while NHL increased from 3.8 to 5.3%. Estimates of the relative risk (RR) of neoplasms in HIV-seropositive populations came from population-based cancer and AIDS registries linkage studies conducted in the United States, Italy and Australia and from a few cohort and case-control studies. In adults with HIV/AIDS, the RR was over 1000 for KS and ranged between 14 for low-grade NHL and over 300 for high-grade NHL. For Hodgkin's disease (HD), a consistent 10-fold higher RR was observed. For cervical and other anogenital tumours associated with human papilloma virus, risk increases were 2- and 12-fold, depending upon location. In Africa, the AIDS epidemic led to KS becoming the most common cancer type in men in several areas. The RR of AIDS-associated tumours were lower in Africa than those reported in western countries.

A case-control study of human immunodeficiency virus infection and cancer in adults and children residing in Kampala, Uganda

Uganda offers a unique setting in which to study the effect of human immunodeficiency virus-1 (HIV-1) on cancer. HIV-1 is prevalent there, and cancers which are known to be HIV-associated, such as Kaposi's sarcoma and Burkitt's lymphoma, are endemic. Adults residing in Kampala, Uganda, presenting with cancer in city hospitals were interviewed and had an HIV test. Of the 302 adults recruited, 190 had cancers with a potentially infectious aetiology (cases). The remaining 112 adults with tumours not known to have an infectious aetiology formed the control group. In addition, 318 children who were also Kampala residents were recruited and tested for HIV: 128 with cancer (cases) and 190 with non-malignant conditions (controls). HIV seroprevalence was 24% in adult controls and 6% in childhood controls. The odds of HIV seropositivity among cases with specific cancers (other than Kaposi's sarcoma in adults) were compared with that among controls, using odds ratios (ORs), estimated with unconditional logistic regression. All ORs were adjusted for age (<5, 5-14, 15-19, 30-44, 45+) and sex and, in adults, also for the number of lifetime sexual partners (1 or 2, 3-9, 10+). In adults, HIV infection was associated with a significantly (p < 0.05) increased risk of non-Hodgkin's lymphoma [OR = 6.2, 95% confidence interval (CI) 1.9-19.9, based on 21 cases] and conjunctival squamous-cell carcinoma (OR = 10.9, 95% CI 3.1-37.7, based on 22 cases) but not with cancer at other common sites, including liver and uterine cervix. In children, HIV infection was associated with a significantly increased risk of Kaposi's sarcoma (OR = 94.9, 95% CI 28.5-315.3, based on 36 cases) and Burkitt's lymphoma (OR = 7.5, 95% CI 2.8-20.1, based on 33 cases) but not with other cancers. The pattern of HIV-associated cancers in Uganda is broadly similar to that described elsewhere, but the relative frequency of specific cancers, such as conjunctival carcinoma, in HIV-infected people differs.

Cancer incidence in Blantyre, Malawi 1994-1998

In this paper, we report the first results from the population-based cancer registry for Blantyre district, Malawi, for the period 1994-1998. In this 5-year period, 1245 cases were recorded in males (an estimated age-standardized incidence of 92.0 per 100,000) and 1003 in females (an age standardised rate (ASR) of 88.8 per 105). The overall percentage of cases with histological verification was just 41.8%, indicating that case-finding outside the laboratory had been quite successful; nevertheless the rather low rates suggest possible underdiagnosis of cancer, as well as cases missed. As in other reports from the region, the contemporary pattern is dominated by Kaposi's sarcoma (KS) (55.2% cancers in men, 28% in women), the effect of the evolving epidemic of AIDS. The incidence of cervix cancer in women is high (ASR 26.2 per 105), and there are moderately high rates of oesophageal cancer (ASR 15.4 per 105 in men, 9.3 per 105 in women). In childhood, the cancer profile is dominated by Burkitt's lymphoma, which accounts for 42.4% of cancers; KS is now the second most frequent cancer of childhood.

Non-Hodgkin lymphoma in Uganda: a case-control study

BACKGROUND

Lymphomas are a relatively common complication of AIDS in western countries, but little is known of the impact of the AIDS epidemic in Africa on the risk of these tumours.

OBJECTIVE

To investigate the types of non-Hodgkin lymphoma (NHL) occurring in Kampala, Uganda, their association with Epstein-Barr virus (EBV), and how their risk is modified by HIV and other variables.

METHODS

A case-control study comparing NHL cases with age/sex-matched controls. Lymphoma cases included 50 histologically diagnosed adults (31 with validation and phenotyping) and 132 histologically diagnosed children (61 with validation and phenotyping). Controls were adults with cancers unrelated to HIV and children with non-infectious diseases.

RESULTS

Most (90%) childhood lymphomas were EBV-positive Burkitt's lymphoma (BL), with no association with HIV. Adult lymphoma cases were mainly BL (mostly EBV positive) or diffuse B cell lymphomas (71%). Only a weak association was found with HIV infection; a more precise estimate was obtained with the total series (OR 2.2, 95% CI 0.9-5.1) than validated/phenotyped cases (OR 2.1, 95% CI 0.3-6.7). Higher socioeconomic status adults, who travelled away from home, or had a history of sexually transmitted diseases, appeared to have a moderately increased risk of lymphoma.

CONCLUSION

Childhood lymphomas were predominantly endemic BL, the risk of which was not modified by HIV. In adults, the risk associated with HIV was much lower in Uganda than in western countries, possibly because of the poor survival of immunosuppressed HIV-positive individuals. Future studies will require careful attention to subtyping of lymphomas, to investigate the possible differences between them.

The spectrum of HIV-1 related cancers in South Africa

Despite the high prevalence of infection by the Human Immunodeficiency Virus (HIV) in South Africa, information on its association with cancer is sparse. Our study was carried out to examine the relationship between HIV and a number of cancer types or sites that are common in South Africa. A total of 4,883 subjects, presenting with a cancer or cardiovascular disease at the 3 tertiary referral hospitals in Johannesburg, were interviewed and had blood tested for HIV. Odds ratios associated with HIV infection were calculated by using unconditional logistic regression models for 16 major cancer types where data was available for 50 or more patients. In the comparison group, the prevalence of HIV infection was 8.3% in males and 9.1% in females. Significant excess risks associated with HIV infection were found for Kaposi's sarcoma (OR=21.9, 95% CI=12.5-38.6), non-Hodgkin lymphoma (OR=5.0, 95%CI=2.7-9.5), vulval cancer (OR=4.8, 95%CI= 1.9-12.2) and cervical cancer (OR= 1.6, 95%CI= 1.1-2.3) but not for any of the other major cancer types examined, including Hodgkin disease, multiple myeloma and lung cancer. In Johannesburg, South Africa, HIV infection was associated with significantly increased risks of Kaposi's sarcoma, non-Hodgkin lymphoma and cancers of the cervix and the vulva. The relative risks for Kaposi's sarcoma and non-Hodgkin lymphoma associated with HIV infection were substantially lower than those found in the West.

Human immunodeficiency virus infection and invasive cervical cancer in South Africa

PURPOSE

The goal of this study was to determine whether South African HIV-seropositive women with invasive cervical cancer present with disease that is more advanced than that of HIV-seronegative women and whether degree of immunosuppression affects the extent of disease at initial presentation.

METHODS

This study is a retrospective review of 60 HIV-seropositive and 776 HIV-seronegative new cases of invasive cervical carcinoma seen at the combined gynecologic oncology unit of the University of the Witwatersrand, Johannesburg, South Africa.

RESULTS

The HIV seroprevalence was 7.2%. Squamous cell carcinoma was the histologic subtype in more than 90% of both cohorts of patients. Although the HIV-positive patients presented with invasive cervical cancer almost 10 years earlier than the HIV-negative patients, i.e., mean age 44 years +/- 9.8 versus 53 years +/- 12.7, respectively (P </= 0.001), there was no difference in the distribution of advanced lesions in the two groups, i.e., 65% in HIV-positive and 55.4% in HIV-negative patients (P = 0.177). At initial diagnosis 26 of the HIV-seropositive patients had a CD(4) cell count less than 200/mm(3), 20 (77%) of whom presented with stage III or IV cervical cancer; the remaining 34 had a CD(4) cell count above 200/mm(3), 19 (56%) of whom had advanced-stage disease. This was not significantly different (P = 0.109). However, HIV-seropositive patients with CD(4) cell counts less than 200/mm(3) had significantly more advanced-stage disease than HIV-seronegative patients, i.e., 77% versus 55.8% respectively (P = 0.041).

CONCLUSION

HIV-seropositive patients presented with invasive cervical cancer almost 10 years earlier than HIV-seronegative patients. Even though HIV seropositivity on its own did not appear to adversely affect extent of disease at presentation, patients with CD(4) cell counts below 200/mm(3) are significantly more likely to have advanced-stage disease at initial diagnosis than HIV-negative patients.

Advances in the epidemiology of HIV-associated non-Hodgkin's lymphoma and other lymphoid neoplasms

The spectrum of HIV-related lymphoid malignancies certainly includes non-Hodgkin's lymphoma (NHL; i.e., chiefly large-cell lymphoma and Burkitt's lymphoma), primary lymphoma of the brain (PBL) and, possibly, Hodgkin's disease (HD). Since the mid-1990s, several epidemiological studies have led to better quantification of the burden of lymphomas in HIV-infected populations. AIDS surveillance data from 17 western European countries show that between 1988 and 1997 a total of 7,148 AIDS cases had NHL as the AIDS-defining illness. The yearly number of cases rose steadily from 1988 to 1995 but declined thereafter. As a percentage of AIDS-defining illnesses, NHL increased from 3.6% in 1994 to 4.9% in 1997. Percent increases were observed in different strata by area, age group, sex and HIV-transmission group. To estimate relative risk (RR) of NHL and other lymphoid neoplasms in unselected HIV-seropositive populations, records of population-based cancer registries and AIDS registries were linked in the United States, Italy and Australia. RRs for NHL in adults with HIV/AIDS ranged between 14 (for low-grade NHL) to over 300 (for high-grade NHL). For HD, the RR was approximately 10. Limited findings from studies based on death certificates and cohorts of HIV-seropositive persons were consistent with those from registry linkage studies. In developing countries, the risk of HIV-associated NHL appears to be much lower than in developed countries, but under-ascertainment and earlier death from other AIDS manifestations may explain the lack of HIV-associated lymphomas in Africa.

First reported case of endometrial carcinoma in association with HIV infection

Endometrial adenocarcinoma is the most common gynecologic cancer in developed countries, although it has never before been documented in a female infected with human immunodeficiency virus (HIV). By contrast, cervical carcinoma is well described in association with HIV infection and in 1993 was added to the AIDS case definition. We present the unique case of a 38-year-old HIV-infected female with endometrial carcinoma, who became rapidly disseminated following her initial surgery. Although HIV is unlikely to have an etiologic role in endometrial carcinoma, it is conceivable that immunosuppression contributed to an accelerated course of her malignancy.

Breast Cancer and HIV: What Do We Know?

The present acquired human immunodeficiency syndrome-defining neoplasms are Kaposi's sarcoma, non-Hodgkins lymphoma, and cervical cancer. However, other malignancies have recently been associated with human immunodeficiency virus (HIV) infection. Is there also a link between breast cancer and HIV infection? Breast cancer seems to be more aggressive in the setting of immunocompromise by HIV infection, as demonstrated by the clinical course of two patients recently treated at this institution and review of the available literature. As the acquired human immunodeficiency syndrome epidemic affects increasing numbers of women and survival improves, surgeons will be frequently called on to diagnose and treat breast cancer in the HIV+ patient.

Association between human immunodeficiency virus type 1 infection and cancer in the black population of Johannesburg and Soweto, South Africa

A case-control study of 913 black cancer patients (aged 15-50 years) was undertaken to measure the association between human immunodeficiency (HIV) infection and cancers believed to have an infective aetiology. Controls were patients with cancers believed not to be infective in origin. The prevalence of HIV in the controls of 7.3% (24 of 325) was similar to the background HIV seropositivity in this population. Odds ratios (ORs) and 95% confidence intervals (CI) adjusted for age, year of diagnosis, marital status and sex were calculated. There was a strong association between HIV infection and Kaposi's sarcoma (KS), with 27 of 33 cases being HIV seropositive, OR = 61.8 (95% CI 19.7-194.2) and an elevated association with non-Hodgkin's lymphoma (NHL), with 27 of 40 cases being HIV seropositive [OR = 4.8 (95% CI 1.5-14.8)]. The elevated odds ratio for KS associated with HIV infection accords with the observed increases in the incidence of KS in several sub-Saharan African countries where the prevalence of HIV is high. The odds ratio for NHL associated with HIV infection was lower than that reported in developed countries, and the reason for this is not clear. No other cancers, including cervical and liver cancers, showed significantly elevated odds ratios associated with HIV infection.

A review of the aetiology of squamous cell carcinoma of the conjunctiva

Squamous cell carcinoma of the conjunctiva is a rare tumour with a multifactorial aetiology. There is strong epidemiological evidence that exposure to solar ultraviolet radiation is an important cause and that HIV infection predisposes to its development. The role of other factors, such as human papillomavirus infection, is unclear.

Effect of ambient solar ultraviolet radiation on incidence of squamous-cell carcinoma of the eye

BACKGROUND

We have investigated the geographic distribution of squamous-cell carcinoma of the eye to assess whether solar ultraviolet light is a risk factor for this disease.

METHODS

We used routinely collected population-based cancer incidence data and published measurements of ambient solar ultraviolet light in our analysis.

FINDINGS

The incidence of squamous-cell carcinoma of the eye declined by 49% of each 10 degrees increase in latitude (p < 0.0001), falling from more than 12 cases per million per year in Uganda (latitude 0.3(0)) to less than O.2 per million per year in the UK (latitude > 50(0)). Solar ultraviolet radiation decreases with increasing latitude, and the incidence of squamous-cell carcinoma of the eye decreased by 29% per unit reduction in ultraviolet exposure (p < 0.0001).

INTERPRETATION

Our results are compatible with the hypothesis that exposure to solar ultraviolet light is an important cause of squamous-cell carcinoma of the eye.

Cancer in Rwanda

Data are presented on the frequency of malignant tumours registered at the population-based cancer registry in the southern prefecture of Butare, Rwanda, from May 1991 until 2 months before the outbreak of civil war in April 1994. Beginning in 1992, subjects were also interviewed about socio-demographic and life-style factors that have been associated with cancer risk in the West. The distribution of cancer in Rwanda is similar to that in other countries in sub-Saharan Africa. The most frequent cancers are those with possible infectious aetiologies: liver cancer (12%), cervical cancer (12%) and stomach cancer (9%). In addition, cancers known to be associated with HIV infection are relatively frequent (Kaposi's sarcoma [6%] and non-Hodgkin's lymphoma [3%]). Chronic infection, including infection with HIV, high parity and multiple sexual partners are important determinants of cancer incidence in this population. Tobacco consumption is low in Rwanda and there are few tobacco-related tumours, such as lung and laryngeal cancer. Other tumours believed to be associated with aspects of Western life-style, such as colorectal and breast cancer, are also relatively infrequent.