Kaposi sarcoma-associated herpesvirus in non-Hodgkin lymphoma and reactive lymphadenopathy in Uganda

Malignancy and viral infections in Sub-Saharan Africa: A review

The burden of malignancy related to viral infection is increasing in Sub-Saharan Africa (SSA). In 2018, approximately 2 million new cancer cases worldwide were attributable to infection. Prevention or treatment of these infections could reduce cancer cases by 23% in less developed regions and about 7% in developed regions. Contemporaneous increases in longevity and changes in lifestyle have contributed to the cancer burden in SSA. African hospitals are reporting more cases of cancer related to infection (e.g., cervical cancer in women and stomach and liver cancer in men). SSA populations also have elevated underlying prevalence of viral infections compared to other regions. Of 10 infectious agents identified as carcinogenic by the International Agency for Research on Cancer, six are viruses: hepatitis B and C viruses (HBV and HCV, respectively), Epstein-Barr virus (EBV), high-risk types of human papillomavirus (HPV), Human T-cell lymphotropic virus type 1 (HTLV-1), and Kaposi's sarcoma herpesvirus (KSHV, also known as human herpesvirus type 8, HHV-8). Human immunodeficiency virus type 1 (HIV) also facilitates oncogenesis. EBV is associated with lymphomas and nasopharyngeal carcinoma; HBV and HCV are associated with hepatocellular carcinoma; KSHV causes Kaposi's sarcoma; HTLV-1 causes T-cell leukemia and lymphoma; HPV causes carcinoma of the oropharynx and anogenital squamous cell cancer. HIV-1, for which SSA has the greatest global burden, has been linked to increasing risk of malignancy through immunologic dysregulation and clonal hematopoiesis. Public health approaches to prevent infection, such as vaccination, safer injection techniques, screening of blood products, antimicrobial treatments and safer sexual practices could reduce the burden of cancer in Africa. In SSA, inequalities in access to cancer screening and treatment are exacerbated by the perception of cancer as taboo. National level cancer registries, new screening strategies for detection of viral infection and public health messaging should be prioritized in SSA's battle against malignancy. In this review, we discuss the impact of carcinogenic viruses in SSA with a focus on regional epidemiology.

Characteristics and survival for HIV-associated multicentric Castleman disease in Malawi

Introduction

Clinical reports of multicentric Castleman disease (MCD) from sub-Saharan Africa (SSA) are scarce despite high prevalence of HIV and Kaposi sarcoma-associated herpesvirus (KSHV). Our objective is to describe characteristics and survival for HIV-associated MCD patients in Malawi. To our knowledge, this is the first HIV-associated MCD case series from the region.

Methods

We describe HIV-positive patients with MCD in Lilongwe, and compare them to HIV-associated lymph node Kaposi sarcoma (KS) and non-Hodgkin lymphoma (NHL) patients treated at our centre. All patients were enrolled into a prospective longitudinal cohort study at a national teaching hospital and cancer referral centre serving half of Malawi's 16 million people. We included adult patients≥18 years of age with HIV-associated MCD (n=6), lymph node KS (n=5) or NHL (n=31) enrolled between 1 June 2013 and 31 January 2015.

Results and discussion

MCD patients had a median age of 42.4 years (range 37.2–51.8). All had diffuse lymphadenopathy and five had hepatosplenomegaly. Concurrent KS was present for one MCD patient, and four had performance status ≥3. MCD patients had lower median haemoglobin (6.4 g/dL, range 3.6–9.3) than KS (11.0 g/dL, range 9.1–12.0, p=0.011) or NHL (11.2 g/dL, range 4.5–15.1, p=0.0007). Median serum albumin was also lower for MCD (2.1 g/dL, range 1.7–3.2) than KS (3.7 g/dL, range 3.2–3.9, p=0.013) or NHL (3.4 g/dL, range 1.8–4.8, p=0.003). All six MCD patients were on antiretroviral therapy (ART) with median CD4 count 208 cells/µL (range 108–1146), and all with HIV RNA <400 copies/mL. Most KS and NHL patients were also on ART, although ART duration was longer for MCD (56.4 months, range 18.2–105.3) than KS (14.2 months, range 6.8–21.9, p=0.039) or NHL (13.8 months, range 0.2–98.8, p=0.017). Survival was poorer for MCD patients than lymph node KS or NHL.

Conclusions

HIV-associated MCD occurs in Malawi, is diagnosed late and is associated with high mortality. Improvements in awareness, diagnostic facilities, treatment and supportive care are needed to address this likely under-recognized public health problem in SSA.

Pediatric Pathology Services in Africa

Context.—Like other pathology services in developing settings, pediatric pathology in Africa is faced with major challenges such as limited access to resources and few opportunities for professional advancement. Additionally, the discrepancy between the large burden of pediatric diseases, many of which individually are rare enough to prove challenging to the general pathologist, and the amount of specialized training available compounds the underlying problems and makes the provision of a high-quality service difficult. Pediatric neoplasms in particular are a chief cause for concern among general pathologists practicing in Africa.

Objectives.—To provide relevant pediatric pathology information with an emphasis on pediatric malignancies to pathologists practicing in Africa, where children represent a very high proportion of the population and training in pediatric pathology is incomplete.

Data Sources.—Authors' experience and relevant literature.

Conclusions.—The limitations inherent in working within a low-resource setting may be reduced by thoughtful and purposeful triaging of specimens, prudent use of cytology in facilitating rapid and inexpensive diagnoses, and collaboration within and outside of the continent. Increased investment in and advocacy for child health, including the creation of additional hospitals dedicated to the care of children, are likely necessary to significantly advance children's health in the region.

Meeting the challenge of hematologic malignancies in sub-Saharan Africa

Cancer is a leading cause of death and disability in sub-Saharan Africa and will eclipse infectious diseases within the next several decades if current trends continue. Hematologic malignancies, including non-Hodgkin lymphoma, leukemia, Hodgkin lymphoma, and multiple myeloma, account for nearly 10% of the overall cancer burden in the region, and the incidence of non-Hodgkin lymphoma and Hodgkin lymphoma is rapidly increasing as a result of HIV. Despite an increasing burden, mechanisms for diagnosing, treating, and palliating malignant hematologic disorders are inadequate. In this review, we describe the scope of the problem, including the impact of endemic infections, such as HIV, Epstein-Barr virus, malaria, and Kaposi sarcoma-associated herpesvirus. We additionally describe current limitations in hematopathology, chemotherapy, radiotherapy, hematopoietic stem cell transplantation, and supportive care and palliation. We review contemporary treatment and outcomes of hematologic malignancies in the region and outline a clinical service and research agenda, which builds on recent global health successes combating HIV and other infectious diseases. Achieving similar progress against hematologic cancers in sub-Saharan Africa will require the sustained collaboration and advocacy of the entire global cancer community.

Accuracy of Burkitt lymphoma diagnosis in constrained pathology settings: importance to epidemiology

CONTEXT

Burkitt lymphoma (BL) is endemic in Uganda and because of the high incidence, diagnosis is often presumed during clinical care and epidemiologic studies.

OBJECTIVES

To assess the accuracy of the clinical and the local pathology diagnosis of BL as assessed by an outside pathology review diagnosis and to understand the limitations on histopathology practice in a resource-constrained setting at 1 hospital in Uganda.

DESIGN

Clinically presumed pediatric (<15 years) BL cases with biopsies and pathology reports, from 1993 to 2007, were identified at St Mary's Hospital, Lacor (Gulu, Uganda). Local histopathology procedures, hematoxylin-eosin-stained tissue sections, and formalin-fixed paraffin-embedded blocks were reviewed onsite by an outside pathologist, followed by outside study that included tissue microarray immunohistochemistry and in situ hybridization.

RESULTS

Local pathology laboratory procedures were inconsistent and suboptimal, especially for tissue fixation. There were 88 clinically presumed BL cases. Sixty-three could be reviewed by outside pathology (25 cases of lost blocks or no remaining tumor) and showed a clinical diagnostic accuracy of 75% (47 confirmed of 63), with a possible range of 62% to 85%, depending on the actual diagnosis of the 25 nonevaluable cases. There were 64 BL cases diagnosed by local pathology. Forty-five could be reviewed by outside pathology (19 cases of lost blocks or no remaining tumor) and showed a local pathology diagnostic accuracy of 82% (37 confirmed of 45), with a possible range of 58% to 88%, depending on the actual diagnosis of the 19 nonevaluable cases. Non-BL diagnoses included other non-Hodgkin lymphomas, Hodgkin lymphoma, and benign infectious lymphadenopathy.

CONCLUSIONS

Accuracy of clinical diagnosis of BL was reduced by inclusion of other diseases with similar clinical presentations. Local pathology, using morphology alone, only marginally improved clinical accuracy and often could not support outside pathology review due to inadequate laboratory procedures. There is an urgent need to improve pathology services in Uganda before conducting high-quality clinical and epidemiologic studies.

EBV, HHV8 and HIV in B cell non Hodgkin lymphoma in Kampala, Uganda

BACKGROUND

B cell non Hodgkin lymphomas account for the majority of lymphomas in Uganda. The commonest is endemic Burkitt lymphoma, followed by diffuse large-B-cell lymphoma (DLBCL). There has been an increase in incidence of malignant lymphoma since the onset of the HIV/AIDS pandemic. However, the possible linkages of HHV8 and EBV to the condition of impaired immunity present in AIDS are still not yet very clearly understood.

OBJECTIVES

1. To describe the prevalence of Epstein-Barr virus, Human Herpes virus 8 and Human Immunodeficiency Virus-1 in B cell non Hodgkin lymphoma biopsy specimens in Kampala, Uganda.2. To describe the histopathology of non Hodgkin lymphoma by HIV serology test result in Kampala, Uganda

METHOD

Tumour biopsies specimens from 119 patients with B cell non Hodgkin lymphoma were classified according to the WHO classification. Immunohistochemistry was used for detection of HHV8 and in situ hybridization with Epstein Barr virus encoded RNA (EBER) for EBV. Real time and nested PCR were used for the detection of HIV.The patients from whom the 1991-2000 NHL biopsies had been taken did not have HIV serology results therefore 145 patients biopsies where serology results were available were used to describe the association of HIV with non Hodgkin lymphoma type during 2008-2009.

RESULTS

In this study, the majority (92%) of the Burkitt lymphomas and only 34.8% of the diffuse large B cell lymphomas were EBV positive. None of the precursor B lymphoblastic lymphomas or the mantle cell lymphomas showed EBV integration in the lymphoma cells.None of the Burkitt lymphoma biopsies had HIV by PCR. Of the 121 non Hodgkin B cell lymphoma patients with HIV test results, 19% had HIV. However, only 1(0.04%) case of Burkitt lymphoma had HIV. All the tumours were HHV8 negative.

CONCLUSIONS

The majority of the Burkitt lymphomas and two fifths of the diffuse large B cell lymphomas had EBV. All the tumours were HHV8 negative. Generally, the relationship of NHL and HIV was weaker than what has been reported from the developed countries. We discuss the role of these viruses in lymphomagenesis in light of current knowledge.

Characterization of Lymphomas in a high prevalence HIV setting

BACKGROUND

HIV infection has been associated with an increased risk of malignancy, both AIDS defining and non-AIDS defining.

METHODS

This study presents a detailed pathological description of newly diagnosed lymphomas in Johannesburg, South Africa (January 2004 and December 2006). The review coincides with introduction of combination antiretroviral therapy.

RESULTS

One thousand eight hundred and ninety-seven new lymphoproliferative disorders were referred to the Charlotte Maxeke Johannesburg Academic Hospital. B-cell non-Hodgkin lymphoma accounted for 83%, T-cell non-Hodgkin lymphoma 3.5%, and Hodgkin lymphoma 7% of cases. The overall prevalence of HIV infection was 37% (n = 709). Diffuse large B-cell lymphoma (21%; n = 401) was the most common lymphoma. HIV prevalence ranged from an absence in follicular or mantle cell lymphoma to a low prevalence in diseases like small lymphocytic lymphoma/chronic lymphocytic leukemia (4%) and pre-B/common ALL (5%) to a high prevalence in diffuse large B-cell lymphoma (80%), Burkitt lymphoma/leukemia (86%), and primary effusion lymphoma (100%).

CONCLUSIONS

This study provides a baseline for monitoring the impact of HIV and management thereof on lymphoma trends. The high prevalence of HIV in certain lymphoma categories emphasizes the need for capacity to diagnose and manage dual conditions. This study highlights the need for strengthening of cancer registries within South Africa and the region.

Synchronous follicular lymphoma, kaposi sarcoma, and castleman's disease in a HIV-negative patient with EBV and HHV-8 coinfection

The authors describe the case of a 65-year-old woman who was HIV negative and had a lymph node biopsy that showed concurrent follicular lymphoma (FL; grade 3A), Kaposi sarcoma (KS), and Castleman's disease (CD) with coinfection by human herpes virus-8 (HHV-8) and Epstein-Barr virus (EBV). The lymphoma was positive for CD20, CD10, and BCL6 and negative for BCL2. Flow cytometry showed a clonal lambda B-cell population, and polymerase chain reaction (PCR) showed a clonal immunoglobulin heavy chain gene rearrangement, confirming a neoplastic B-cell process. Focally, the FL component showed numerous EBER1-positive cells, with rare HHV-8-positive cells. The KS component showed strong HHV-8 expression with rare EBER1-positive cells. The CD component showed scattered HHV-8, viral interleukin-6, and EBER1-positive cells. The simultaneous occurrence of a FL, KS, and CD in an HIV-negative patient expands the spectrum of HHV-8-positive neoplasms and suggests the possibility of HHV-8 rendering mature B-cells hyperresponsive to antigenic stimulation, providing an expanded target for second site mutations or cytokine-driven hyperplasia, culminating in lymphoma.

Infectious aetiology of Hodgkin and non-Hodgkin lymphomas: a review of the epidemiological evidence

Lymphomas constitute a heterogeneous group of malignant disorders with different clinical behaviours, pathological features and epidemiological characteristics. For some lymphoma subtypes, epidemiological evidence has long pointed to infectious aetiologies. A subset of Hodgkin lymphoma is strongly linked to Epstein-Barr virus (EBV) infection. In addition, infectious agents can directly infect and transform lymphocytes (e.g. EBV, human herpesvirus 8), induce immunosuppression (human immunodeficiency virus), or cause chronic immune stimulation (hepatitis C virus, Helicobacter pylori), all of which may play a role in the development of various non-Hodgkin lymphoma subtypes. Here, we review the epidemiological evidence linking infections with malignant lymphoma.