Evaluation of the NucliSens EasyQ assay in HIV-1-infected individuals in South Africa

We compared the performance of the NucliSens EasyQ assay (bioMerieux) combined with the manual NucliSens miniMag extraction methodology to the Roche Cobas Ampliprep/Standard Amplicor Monitor methodology (Roche Diagnostics) for HIV-1 RNA quantitation in HIV-1-infected individuals in South Africa. Plasma samples (284) from HIV sero-positive patients at different stages of infection were analyzed. The distribution of results was typical of the clinical samples received at the laboratory where 20% have viral load results <400 copies/ml (2.6 log) and 18% have viral load results >750000 copies/ml (5.8 log) using the Roche Amplicor Monitor standard assay. All statistical analyses were performed using log10-transformed values for all the variables in the analyses, i.e. log10EasyQIU/ml, and log10RNA (log10 copies/ml, Amplicor). Roche values were converted from RNA copies per ml to IU/ml by multiplying the Roche value by 0.51. HIV RNA levels quantitated by the NucliSens EasyQ assay correlated significantly with those of the Roche Cobas Amplicor Monitor assay (r=0.874, p<0.0001). Reproducibility of the NucliSens EasyQ assay in the log6IU range yielded CV variance of 1.3-2.84% for two well-trained technologists. In addition, a retrospective evaluation of the performance of the NucliSens EasyQ assay in 102 runs (2448) samples was conducted in the laboratory over a 4-month interval. Factors considered during this evaluation included time taken to perform the assay, volume requirements, number of required repeats, potential for contamination.

Hematologic malignancies in South Africa 2000-2006: analysis of data reported to the National Cancer Registry

Little is known about the incidence patterns of hematologic malignancies in Sub-Saharan Africa, including South Africa. We estimated incidence rates of pathology-confirmed adult cases of leukemia, myeloma and related diseases (myeloma), Hodgkin lymphoma (HL), and non-Hodgkin lymphoma (NHL) reported to the National Cancer Registry of South Africa (NCR) between 2000 and 2006, by age, gender, and population group (Black, White, Coloured, Asian/Indian). Gender-specific age-standardized rates were calculated overall and by population group and incidence rate ratios (IRRs) were estimated using Poisson regression models. Between 2000 and 2006, there were 14662 cases of leukemia, myeloma, HL, and NHL reported to the registry. Incidence rates of reported hematologic malignancies were generally 20-50% higher among males than females. Our analyses suggested marked differences in the rates of reported hematologic malignancies by population group which were most pronounced when comparing the White versus Black population groups (IRRs ranging from 1.6 for myeloma to 3.8 for HL for males and females combined). Challenges related to diagnosis and reporting of cancers may play a role in the patterns observed by population group while the set-up of the NCR (pathology-based) could lead to some degree of under-ascertainment in all groups. This is the first country-wide report of the incidence of hematologic malignancies in South Africa. Despite challenges, it is important to analyze and report available national cancer incidence data to raise awareness of the cancer burden and to characterize patterns by demographic characteristics so as ultimately to improve the provision of cancer-related health care.

Plasmablastic lymphoma in Johannesburg, South Africa, in the era of widescale antiretroviral therapy use

OBJECTIVES

Plasmablastic lymphoma (PBL) is a clinically aggressive lymphoma which has a predilection for extranodal sites and is frequently HIV-associated. The incidence of non-Hodgkin lymphoma is thought to be reduced by widescale antiretroviral therapy (ART) coverage, but the literature is sparse as regards the impact of ART on the incidence of PBL and its outcomes in South Africa (SA). This study aimed to compare factors of interest in cases of PBL diagnosed before and after the widespread availability of ART in Johannesburg, SA.

METHODS

All cases of PBL diagnosed in the state sector hospitals of Johannesburg in 2007 and 2017 (before and after the widespread availability of ART, respectively) were extracted from the laboratory information system, and factors of interest compared.

RESULTS

The majority (> 95%) of cases of PBL were seen among people with HIV infection (PWH) at both time-points, and the proportion of patients on ART and with virological suppression (VS) increased significantly in 2017. However, the number of cases of PBL did not differ significantly between the two years assessed, comprising 46/397 (11.6%) and 53/582 (9.6%) of all lymphomas in 2007 and 2017, respectively (P = 0.23). Ongoing risk for PBL among PWH with virological control and immunological recovery was evident in 2017, as 18.9% of the patients had both VS and CD4 counts > 200 cells/μL at diagnosis. Inferior survival times were associated with elevated lactate dehydrogenase (LDH) levels and Epstein Barr virus (EBV) negativity, but were not influenced by the presence of AIDS, ART or VS. EBV negativity was significantly associated with VS, and appeared to flag a particularly aggressive form of the disease.

CONCLUSIONS

Widescale ART coverage has not reduced the incidence of PBL in Johannesburg, and an ongoing risk for this disease among PWH with adequate virological control and immunological recovery persists.

Hepatosplenic T-cell lymphoma: A case series

Hepatosplenic T-cell lymphoma (HSTCL) is a rare type of Non-Hodgkin Lymphoma (NHL), grouped under the mature or peripheral T-cell lymphomas. It is characterised by extranodal infiltration and proliferation of malignant T-cells within the sinusoids of the liver, sinuses and red pulp of the spleen, and the bone marrow. The tumour cells express CD2 and CD3, but are CD4, CD5 and CD8 negative and express a clonally restricted gamma-delta (or less commonly alpha-beta) T-cell receptor. The disease has an aggressive clinical course associated with a poor prognosis. We highlight and report three patients from South Africa with HSTCL, all of whom had hepatosplenomegaly and cytopaenias, and despite being HIV seronegative and immunocompetent, had a poor outcome, with a mean survival of 7.5 months in the two evaluable patients. This rare entity has not previously been reported from South Africa and as yet needs to be adequately characterised in a population where lymphoma is the most common haematological malignancy in adults, and where approximately two thirds of the adult lymphoma population are HIV seropositive.

Changing Patterns of Lymphoma in the Antiretroviral Therapy Era in Johannesburg, South Africa

BACKGROUND

South Africa has a high HIV prevalence, which associates with an increased risk of lymphoma. Antiretroviral therapy (ART) became accessible in 2004, but the program has substantially expanded. Changes in lymphoma patterns are documented in high-income countries after wide-scale ART including declining high-grade B-cell non-Hodgkin lymphomas (HG B-NHLs), particularly diffuse large B-cell lymphoma, and increased Hodgkin lymphoma (HL). There are limited data from Africa. This study aimed to compare HG B-NHL characteristics in the early (2007) and later (2017) ART era.

METHODS

All incident lymphomas at the National Health Laboratory Service, Johannesburg, were identified using the laboratory information system, and data were collected for each patient.

RESULTS

The total number of lymphoma cases increased from 397 (2007) to 582 (2017). This was associated with improved lymphoma classification and patient referral for oncological care. HG B-NHL remained the most diagnosed lymphoma subtype in 2017 comprising 70% of HIV-associated lymphomas, followed by HL (24%). Diffuse large B-cell lymphoma comprised 65% of all HG B-NHLs and 45% of all lymphomas in people with HIV in 2017. Significantly more patients were on ART in 2017, with improvements in virological control documented. Despite this, 47.6% of patients were not virologically suppressed, and 37.5% of patients were ART-naive at time of diagnosis in 2017. Immunological reconstitution was suboptimal, which may reflect late initiation of ART.

CONCLUSION

Public health initiatives to initiate ART as early as possible and to retain patients in ART programs may assist in decreasing the number of HIV-associated lymphomas in our setting.

Immature platelet fraction levels in a variety of bone marrow pathologies in South African HIV-positive patients with thrombocytopenia

OBJECTIVES

Thrombocytopenia is common in HIV-infected individuals and often requires a diagnostic bone marrow examination. Interpretation may, however, be limited due to the multifactorial nature of HIV-associated thrombocytopenia and the difficulty in assessing megakaryocyte function morphologically. The immature platelet fraction (IPF) is a parameter which reportedly reflects megakaryocyte activity, with an IPF >7.7% suggesting increased platelet production. The aim of this study was to correlate the IPF with the bone marrow findings as well as other clinical variables of interest in South African patients with HIV-associated thrombocytopenia.

METHODS

Seventy-eight HIV-positive patients with thrombocytopenia were enrolled from the Charlotte Maxeke Johannesburg Academic Hospital. The IPF levels were measured using a Sysmex XE-5000 haematology analyzer and were correlated with bone marrow and other findings.

RESULTS

The median IPF was 7.6%, ranging from 1.3 to 44%. It was raised in 78% of patients with immune thrombocytopenia (ITP) (median = 16.3%) and low in 79% of patients with hypocellular marrow (median = 6.5%). Surprisingly, it was highly variable among patients with malignant marrow infiltration and mycobacterial infection of the bone marrow (BMTB) (median = 8.4 and 7.1%, respectively). Multivariate linear regression analysis confirmed a significant independent inverse relationship between the IPF and hypocellular marrow (P < 0.0001), a marginally significant positive association with ITP (P = 0.059), and the absence of any relationship with malignant infiltration or BMTB. The IPF had a significant inverse association with the platelet count (P = 0.0006), but was unrelated to the CD4 count and exposure to anti-retroviral therapy. Unexpectedly, it showed a significant positive association with the HIV viral load (P = 0.005). We speculate this to reflect increased megakaryocyte activity in compensation for accelerated platelet clearance due to HIV-driven platelet activation.

CONCLUSION

This study investigates the role of the IPF in HIV-associated thrombocytopenia, and emphasizes the limitations of morphological analysis in determining megakaryocyte function.

Preparing for the next pandemic: Lessons from rapid scale-up of SARS-CoV-2 testing in a South African high-throughput automated HIV molecular laboratory

Africa's readiness to respond to the SARS-COV-2 pandemic was tested due to reliance on rapid turn-around-time of polymerase chain reaction results for clinical management, isolation and quarantine decisions. The NHLS HIV Molecular Laboratory in Johannesburg, South Africa, is one of the largest automated HIV molecular laboratories worldwide. Despite its extensive molecular capacity and experience in managing high volumes acquired from a large HIV program, significant challenges were encountered during its rapid transition to large scale SARS-CoV-2 testing. We describe the strategies employed to manage these challenges that resulted in a 30% improvement in SARS-CoV-2 test turn-around-time during the first wave peak during which approximately 25000 samples were tested per month, and further improvement during the second wave peak, with 81% within targeted turn-around-time.

Primary plasma cell leukaemia in a 22-year-old woman: A case report

Introduction

Primary plasma cell leukaemia is a rare and highly aggressive disease that is commonly diagnosed a decade earlier than multiple myeloma, at a median age of 55 years. However, it has also been described in younger patients, as documented in this case report. It often presents with hepatosplenomegaly and lymphadenopathy, whilst the presence of bony lesions are less-commonly seen when compared to multiple myeloma.

Case presentation

This report describes the case of a young woman who presented with symptoms of anaemia and a history of menorrhagia. On further careful examination, she was found to have additional signs and symptoms and was later diagnosed with primary plasma cell leukaemia.

Management and outcome

On admission, the patient received supportive care measures, including blood products. At diagnosis, a specific chemotherapy regimen was commenced; however, this failed to induce remission. The decision to continue with supportive care only was made and the patient died seven months later.

Discussion

This case study is presented because of its rarity, the young age of the patient at presentation and the unusual clinical and laboratory findings. Persistent anaemia unresponsive to standard treatment should raise the index of suspicion and further investigations directed to exclude malignancies should be considered.

Extranodal presentation of a lymphoma with precursor B-cell phenotype and translocation t(8;14) in South Africa

Introduction

A rare entity of a B-cell malignancy with precursor B-cell phenotype and concomitant translocation t(8;14) or variant MYC translocation exists. These cases show clinical, pathological and molecular overlap between precursor B-lymphoblastic leukaemia or lymphoma and Burkitt leukaemia or lymphoma (BLL).

Case presentation

We report a case from February 2019 at the Charlotte Maxeke Johannesburg Academic Hospital, South Africa, of a 9-month-old infant with a predominantly extracranial soft tissue mass showing extradural extension. There was no involvement of the peripheral blood or bone marrow. Fine needle aspiration and Tru-Cut biopsy of the soft tissue scalp mass showed the tumour to be of precursor B-cell phenotype. Contrastingly, an immunophenotypic assessment revealed a high S-phase fraction and raised concern for BLL. This prompted testing for the translocation t(8;14) by fluorescence in-situ hybridisation analysis, which confirmed this aberration.

Management and outcome

Based on the published experience of other centres, the patient was initiated on a BLL protocol. Despite an excellent clinical response, the patient succumbed to neutropenic sepsis six months after diagnosis.

Conclusion

Leukaemia or lymphoma with translocation t(8;14) or variant MYC translocation and precursor B-cell phenotype is a rare entity with a varied clinical presentation. This poses a challenge for diagnosis and classification and a clinical dilemma for the choice of treatment.

T-cell lymphoblastic leukaemia: The Johannesburg state-sector experience

Background: T-cell lymphoblastic leukaemia (T-ALL) is a malignancy of immature T-cells which is reported to comprise 7% – 23% of cases of lymphoblastic leukaemia (ALL), making up a larger proportion of adult ALL than childhood cases. It is characterised by an increased risk for early relapse but reportedly has superior outcomes as compared to B-cell ALL amongst adult patients. The frequency and clinical behaviour of T-ALL in Africa are unknown.Aim: This study aimed to assess the prevalence and selected clinicopathological features of T-ALL in Johannesburg, South Africa (SA).Setting: The Johannesburg state sector.Methods: All cases of ALL diagnosed by flow cytometry in the state-sector hospitals of Johannesburg over 42 months between 2016 and 2019 were identified and pertinent data recorded from the laboratory information system.Results: One hundred and eighty-one cases of ALL were identified, of which 59 (32.6%) were of T-cell lineage. The proportion of adult and paediatric ALL made up by T-ALL was similar (19/54 [35.2%] vs 40/127 [31.5%] respectively). Crude survival rates were very poor, with 80.0% having demised at the time of data collection. The mortality rate was overall significantly poorer amongst patients with T-ALL (80.0%) as compared to those with B-ALL (53.8%; p = 0.005) but was similarly poor in adults with B-ALL (83.3%) vs T-ALL (86.7%) (p = 0.53). The mortality rate did not differ between those with low-risk versus high-risk clinical features (77.8% vs 80.6%; p = 1.00).Conclusion: T-cell lymphoblastic leukaemia makes up a larger proportion of ALL in Johannesburg than is reported elsewhere, and it is a high-risk disease that is not well stratified by conventional risk factors.

Von Willebrand Factor Multimer Patterns in People Living with Human Immunodeficiency Virus Infection

BACKGROUND

Endothelial dysfunction contributes to hypercoagulability in people with HIV (PWH). A surrogate marker of this is elevated von Willebrand factor (VWF) which has been documented in PWH. This study compared VWF multimer patterns in PWH who were anti-retroviral therapy (ART) naive and immune reconstituted on ART.

METHODS

VWF multimer analysis was performed with a semi-quantitative electrophoresis assay on plasma from 79 PWH (39 ART-naive and 40 virally suppressed on ART) and 25 normal control samples.

RESULTS

The total optical density mean VWF level was significantly increased in PWH and higher in ART-naive versus ART-exposed, virally suppressed patients (p < 0.0001). No quantitative difference was demonstrated in the multimer distribution pattern between the groups.

CONCLUSIONS

Our findings suggest that there is no difference in multimer distribution between ART-naive and virally suppressed PWH. Due to a small sample size, confirmation in a larger study is required.

The prognostic impact of monocyte fluorescence, immunosuppressive monocytes and peripheral blood immune cell numbers in HIV-associated Diffuse Large B-cell Lymphoma

INTRODUCTION

Diffuse large B-cell lymphoma (DLBCL) is a high grade non-Hodgkin lymphoma which is common among immunodeficient people. Derangements of peripheral blood immune cells have been described to have a prognostic impact in DLBCL in high income countries, including a monocytosis, the ratios of lymphocytes to both monocytes (L:M) and neutrophils (N:L), as well as the numbers of regulatory T-cells (Tregs) and immunosuppressive monocytes (HLA-DRlow monos). To date, the impact of these variables has not been assessed in the setting of HIV-associated DLBCL (HIV-DLBCL), which is among the most common malignancies seen in people living with HIV. In this study, we assessed these factors in a cohort of South African patients with DLBCL and a high HIV-seropositivity-rate. In addition, we evaluated the prognostic value of monocyte activation (as reflected by monocyte fluorescence (MO-Y) on a Sysmex haematology analyser). This parameter has to date not been assessed in the setting of DLBCL.

METHODS

A full blood count and differential count as well as flow cytometry for HLA-DRlow monocyte and Treg enumeration were performed in patients with incident DLBCL referred to the Chris Hani Baragwanath Academic Hospital in Johannesburg, South Africa between November 2019 and May 2022. Additional clinical and laboratory data were recorded from the patient charts and laboratory information system.

RESULTS

Seventy-six patients were included, of whom 81.3% were people living with HIV with a median CD4 count of 148 cells/ul. Most patients had advanced stage disease (74.8%) and were predominantly treated with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP)-based chemotherapy (without Rituximab). At a median follow-up period of 19 months, the median survival time was 3.5 months, with a 12-month survival rate of 27.0%. All of the immune-cell-related variables (with the exception of the CD4 count) were similar between the people living with HIV and the HIV-negative individuals. In contrast to previous studies, a high monocyte count, the L:M and increased numbers of HLA-DRlow monocytes were not significantly associated with survival in HIV-DLBCL, while a neutrophilia (>8 x 109/L), the N:L (>6:1), high numbers of Tregs (≥5.17% of CD4s) and lymphopenia (<1.3 x 109/L) were. In addition, increased monocyte fluorescence (MO-Y >115.5) was associated with superior outcomes, which we speculate to reflect a more robust antitumour immune response among individuals with high levels of monocyte activation. On Cox Proportional hazard analysis, immune-cell factors independently associated with survival included a CD4 count <150 cells/ul and a neutrophilia.

CONCLUSION

The monocyte count, L:M and the number of HLA-DRlow monos are not strong prognostic indicators in HIV-DLBCL, while a low CD4 count and neutrophilia are. Elevation of the MO-Y shows some promise as a potential biomarker of antitumour immunity; further study in this regard would be of interest.

Derangements of immunological proteins in HIV-associated diffuse large B-cell lymphoma: the frequency and prognostic impact

Introduction

Diffuse large B-cell lymphoma (DLBCL) is an aggressive malignancy of B-cells frequently encountered among people living with HIV. Immunological abnormalities are common in immunocompetent individuals with DLBCL, and are often associated with poorer outcomes. Currently, data on derangements of immunological proteins, such as cytokines and acute phase reactants, and their impact on outcomes in HIV-associated DLBCL (HIV-DLBCL) is lacking. This study assessed the levels and prognostic relevance of interleukin (IL)-6, IL-10 and Transforming Growth Factor Beta (TGFβ), the acute phase proteins C-reactive protein (CRP) and ferritin; serum free light chains (SFLC) (elevation of which reflects a prolonged pro-inflammatory state); and the activity of the immunosuppressive enzyme Indoleamine 2,3-dioxygenase (IDO)in South African patients with DLBCL.

Methods

Seventy-six patients with incident DLBCL were enrolled, and peripheral blood IL-6, IL-10, TGFβ, SFLC and IDO-activity measured in selected patients. Additional clinical and laboratory findings (including ferritin and CRP) were recorded from the hospital records.

Results

Sixty-one (80.3%) of the included patients were people living with HIV (median CD4-count = 148 cells/ul), and survival rates were poor (12-month survival rate 30.0%). The majority of the immunological proteins, except for TGFβ and ferritin, were significantly higher among the people living with HIV. Elevation of IL-6, SFLC and IDO-activity were not associated with survival in HIV-DLBCL, while raised IL-10, CRP, ferritin and TGFβ were. On multivariate analysis, immunological proteins associated with survival independently from the International Prognostic Index (IPI) included TGFβ, ferritin and IL-10.

Conclusion

Derangements of immunological proteins are common in HIV-DLBCL, and have a differential association with survival compared to that reported elsewhere. Elevation of TGFβ, IL-10 and ferritin were associated with survival independently from the IPI. In view of the poor survival rates in this cohort, investigation of the directed targeting of these cytokines would be of interest in our setting.

Tumour-associated macrophages in diffuse large B-cell lymphoma: the prognostic and therapeutic impact in a South African centre with high HIV seroprevalence

Diffuse large B-cell lymphoma (DLBCL) is a common malignancy among people living with HIV. Macrophage enrichment of the tumour microenvironment (TME) is a prognostic factor in DLBCL among immunocompetent people, with some studies reporting that macrophage enrichment predicts a superior response to rituximab therapy. The macrophage phenotype is also important, with reportedly poorer outcomes with enrichment of anti-inflammatory (M2) macrophages. To date, the relationship between the type/number of tumour macrophages and outcomes in HIV-associated DLBCL (HIV-DLBCL) has been poorly explored. In this study, we assessed tumour macrophage numbers in a South African cohort of patients with DLBCL and a high HIV-seropositivity rate. Immunohistochemistry for CD68 and CD163 was performed on the diagnostic biopsies of 79 patients with DLBCL. Relevant information was documented from the clinical records, including disease stage, international-prognostic index score, HIV-related parameters, C-reactive protein, ferritin levels and immune cell numbers (monocytes, lymphocytes and neutrophils). Survival analysis was performed using Kaplan-Meier survival estimates, and the correlation between tumour macrophage numbers and a variety of immunological parameters was assessed using Spearman's rho. Of the 79 patients included, 87.2% were living with HIV, and rituximab therapy was used in 46.9%. Tumour macrophage numbers were not related to HIV status, but low pro-inflammatory (M1) macrophage numbers (CD68 + CD163 -) were significantly associated with poorer outcomes (HR 2.02, p = 0.03). M2 macrophage (CD68 + CD163 +) enrichment was not predictive of survival but was associated with improved response to rituximab therapy (HR 0.19; p = 0.002). Macrophage numbers were marginally correlated with ferritin levels, which showed modest performance as a peripheral blood biomarker of the TME macrophage status (AUC 0.6 at a level of 374 µg/L), and high ferritin levels were associated with a superior response to rituximab-therapy (HR 0.28, p = 0.034). Pro-inflammatory macrophages are important in tumour control in HIV-DLBCL, while M2 macrophage enrichment improves the response to rituximab therapy. Ferritin shows promise as a biomarker for identifying patients more likely to benefit from rituximab therapy.

Infection and myelodysplasia: A case report of GATA2 deficiency in a South African patient

Rare diseases often result in delays in diagnosis. It is important to recognize conditions that have features of both inborn errors of immunity and predispose to myeloid neoplasia. Here we report a patient with GATA2 deficiency that presented with disseminated non-tuberculous mycobacterial infection and pancytopenia secondary to myelodysplastic syndrome.

Validation of the Xpert Breast Cancer STRAT 4 Assay on the GeneXpert instrument to Assess Hormone Receptor, Ki67, and HER2 Gene Expression Status in Breast Cancer Tissue Samples

Breast cancer is the commonest cause of cancer-related mortality in African females where patients often present later and with advanced disease. Causes for delayed diagnosis include restricted diagnostic access and international controversy on interpretation of ancillary tests like immunohistochemistry (IHC). Fine needle aspirates (FNAC) are an attractive alternative although may have reduced sensitivity. The Xpert Breast Cancer STRAT4 (STRAT4) (CE-IVD*) assay (Cepheid, Sunnyvale) is a semi-quantitative reverse-transcription polymerase chain reaction assay which detects messenger RNA (mRNA) expression in breast samples for estrogen receptor ( ESR1 ), progesterone receptor ( PGR1 ), human epidermal growth factor receptor/Erb-B2 receptor tyrosine kinase 2 (HER2/ ERBB2 ) and the proliferation marker, MKi67 . We assessed the performance of this assay on both formalin-fixed paraffin-embedded (FFPE, n=31) and matched FNAC (n=20) samples from patients presenting with breast cancer to the Johannesburg academic hospitals. IHC and Fluorescent in situ hybridization analysis (performed on HER2-indeterminate samples) was compared with the mRNA expression of the corresponding target genes in FFPE samples, and mRNA expression on FNAC samples was compared with the FFPE results for both mRNA expression and IHC. Concordance between IHC/FISH and Xpert Breast Cancer STRAT4 in FFPE and FNAC samples using the Quick lysis (Q) method (a research-use-only modification of the validated FFPE-lysis method), showed an overall percentage agreement for ESR1 expression of 90.3% and 81.3%, and for PGR1 expression at 86.7% and 81.3% respectively in FFPE and FNAC samples. Concordance was lowest for Ki67 expression, using a binary IHC cutoff for Ki67 positivity at ≥20% staining) at 83.9% and 62.5%, for FFPE and FNAC samples, respectively. This suggests that the STRAT4 assay may be a useful ancillary test in determining HR and Ki67 status in FFPE samples and that use on FNAC samples may be feasible. Future studies should expand the sample numbers and establish locally relevant cutoffs.

High Risk Janus Kinase 2 V617F Allele Burden in a Seven-Year Cohort of Patients with Myeloproliferative Neoplasms

BACKGROUND

JAK2 V617F is the most common somatic mutation associated with the classical Philadelphia (Ph) chromosome negative myeloproliferative neoplasms (MPNs), which include essential thrombocythemia (ET), polycythemia vera (PV), and primary myelofibrosis (PMF). JAK2 V617F allele burden may be used for establishing the diagnosis, determining prognosis, and monitoring progression in these diseases. Limited data is available regarding the epidemiology of MPNs in Africa, and there is paucity of data on demographic, laboratory, and clinical features of MPNs in South Africa. This study determined the JAK2 V617F allele burden in a seven-year retrospective cohort of patients diagnosed with MPNs and described the characteristics of these diseases in a South African setting.

METHODS

A laboratory database search was performed to identify patients diagnosed with ET, PV or PMF and a positive JAK2 V617F mutation, diagnosed qualitatively on Fluorescence Resonance Energy Transfer (FRET) real-time PCR and melting curve analysis. The allele burden for these patients was measured on archived residual DNA samples using a quantitative allele specific amplification (QUASA) assay. Demographic data and relevant laboratory results at presentation were analyzed.

RESULTS

The search identified 87 patients who tested positive for JAK2 V617F mutation and fulfilled the diagnostic criteria for ET, PV or PMF from 2012 to 2018. Median age at diagnosis was 64 years with a male: female ratio of 1.2:1. ET, PV and PMF accounted for 11.5%, 44.8%, and 43.7% of the MPNs, respectively. Median allele burden for ET, PV, and PMF was 24.9%, 71.1%, and 55.8%, respectively. Allele burden was significantly lower in ET compared to PV (p = 0.0003) and PMF (p = 0.0023) and correlated with leukocytosis, neutrophilia, eosinophilia, and low erythrocyte mean cell volume (p < 0.05).

CONCLUSIONS

JAK2 V617F-positive MPNs occurred predominantly in older patients with approximately equal gender ratio. ET was the least common MPN and there was a higher proportion of PMF cases than described in studies in Europe and America. Allele burden was also relatively high for all three subtypes of MPNs when compared to other published data, which may predispose to poorer prognosis.

A Rare Prothrombin Gene Mutation C20209T in a South African Patient with Pulmonary Embolism in Pregnancy: a Case Study and Systematic Review

BACKGROUND

The G202010A prothrombin gene mutation is a documented prothrombotic risk factor in Caucasian patients. Several other mutations have been described within the prothrombin gene, predominantly in non-Caucasians, including the C20209T mutation. The clinical significance of this mutation is uncertain, but it has been associated with thrombotic events and pregnancy complications.

METHODS

We describe a 28-year-old black South African woman who presented with pulmonary embolism during pregnancy. She was investigated for underlying prothrombotic biomarkers.

RESULTS

Genetic screening for the prothrombin G202010A mutation by real-time polymerase chain reaction and melting curve analysis demonstrated an atypical mutant peak. Sequencing confirmed a variant C20209T prothrombin mutation.

CONCLUSIONS

This is the first report of the C20209T mutation in the Southern African population. It remains uncertain whether genetic testing should be offered routinely to non-Caucasian patients in a resource-limited setting.

Patterns of incident Burkitt lymphoma during the HIV epidemic among the Black African and White population in South Africa

BACKGROUND

Burkitt lymphoma (BL) may be HIV-associated but data on BL trends in South Africa (SA), where HIV is highly prevalent, are scarce. We compared BL incidence trends over 36 years among Black African and White individuals.

METHODS

We included histologically diagnosed BL from the National Cancer Registry in SA between 1986-2021. We computed yearly age-standardised incidence rates (ASIR) by race, and annual percentage changes in ASIR using Joinpoint regression.

RESULTS

Between 1986-2021, 2205 Black African (ASIR: 1.68/1,000,000; 95% confidence interval [CI] 1.63-1.73) and 366 White individuals (ASIR: 2.34/1,000,000; 95% CI 2.15-2.53) had incident BL. Median age at diagnosis increased over time, while the male proportion among those diagnosed declined. The ASIR among Black Africans increased from 1986-2012 and declined thereafter with BL incidence peaks shifting from children and elderly to middle-aged adults. Among White individuals, BL rates rose among all age groups over time.

CONCLUSIONS

The BL epidemiology among Black Africans, with decreasing rates since 2012, may reflect SA's evolving HIV epidemic. In contrast, BL rates among White individuals in SA and many high-income countries continue to increase over time. Further studies are needed to better understand the differences in BL epidemiology across geographic regions and population groups.