Lymphomas in Ile-Ife, Nigeria: Immunohistochemical Characterization and Detection of Epstein-Barr virus Encoded RNA

Immunophenotypic characterisation of non-Hodgkin lymphomas at a tertiary hospital in Ghana

BACKGROUND

Non-Hodgkin lymphomas (NHLs) are a heterogeneous group of clonal lymphoid tumours originating from lymphocytes. They constitute about 90% of an estimated 3%-4% worldwide distribution of malignant lymphomas among various cancers. Despite the continuous rise and associated deaths, research on NHLs, and in particular the area of immunophenotypic spectrum is limited in Ghana and sub-Saharan Africa.

METHODS

A retrospective, descriptive study in which archived tissue blocks of histologically diagnosed NHLs at a tertiary hospital in Accra, Ghana, were used. Antigenic phenotypes were determined by immunohistochemistry.

RESULTS

A total of 66 cases of NHLs, with a mean age of 50.2 ± 16.1 years, were selected for the study. Among the targeted markers, cluster of differentiation 20 (CD20) was the most commonly expressed in 89.4% (59) cases. Immunohistochemistry studies revealed a greater proportion of B cell lymphomas of 89.4%. Five subtypes were successfully identified, of which diffuse large B cell lymphoma constitutes the predominant group (40.9%). A significant association was observed between phenotypic cell types and outcomes of NHLs (p = 0.011).

CONCLUSION

Adult NHLs were mostly due to the malignant transformation of B cells with diffuse large B cell lymphoma being the commonest subtype. The present study therefore serves as preliminary data for further research towards the adoption of an improved treatment regimen and management of NHLs.

Spectrum of common Hodgkin lymphoma and non-Hodgkin lymphomas subtypes in Zambia: a 3-year records review

BACKGROUND

Lymphomas usually present with different occurrence patterns across different geographical locations, but their epidemiology in Zambia is yet to be extensively explored.

OBJECTIVES

To study the spectrum of lymphoma subtypes prevalent within the Zambian population.

METHODS

Histopathological records with suspected lymphoma at the University Teaching Hospital (UTH) in Lusaka from the year 2014 to 2016, diagnosed based on the 2008 World Health Organization (WHO) criteria were reviewed. The analysis was done in terms of type, sex, age, and site of biopsy; and Fisher's exact test was used for significance testing.

RESULTS

During the study period (2014-2016), there were more B cell neoplasms {222 (92.5%)} than T cell neoplasms {18 (7.5%)}. Non-Hodgkin's lymphoma (NHL) was seen in 191 (79.6%) whereas classic Hodgkin's lymphoma (CHL) was seen in 39 (16.3%). Burkitt's lymphoma (BL) and diffuse large B cell lymphoma (DLBCL) showed equal proportions {17.5% of all lymphoma cases (42/240) each}, as the most prevalent subtypes of NHL whereas marginal zone B cell lymphoma was the rarest subtype with 1.4% (4/240). For CHL, mixed cellularity and lymphocyte rich subtypes (4.6% of all lymphoma cases) were the most common subtypes. There was a statistically significant difference in the occurrences of lymphoma subtypes across different age categories (p = 0.002).

CONCLUSION

Zambia has a diverse lymphoma subtypes population, affecting a relatively young population. The data from this study will serve as a baseline for improved health care provision and more robust future studies.

Clinicopathologic Features of Peripheral T-Cell Lymphoma in Sub-Saharan Africa

OBJECTIVES

Peripheral T-cell lymphomas (PTCLs) are heterogeneous, clinically aggressive, and rare. Subtype distribution varies by geographic location; however, data from sub-Saharan Africa (SSA) are lacking. We sought to elucidate clinicopathologic features of PTCL in SSA.

METHODS

We reviewed PTCL consultation cases from three SSA countries. PTCL subtype was determined per 2017 World Health Organization classification. Cases with sufficient material were evaluated by polymerase chain reaction for human T-cell leukemia virus type 1 (HTLV-1) and T-cell receptor γ (TCRG) rearrangement.

RESULTS

Among 32 cases, median age was 45 years and male-to-female ratio was 1.7. Thirty (94%) of 32 cases required additional workup for subclassification. PTCL, not otherwise specified (PTCL-NOS) was the most common subtype (13/32, 41%), followed by PTCL with T-follicular helper phenotype (6/32, 19%) and systemic anaplastic large cell lymphoma (6/32, 19%). Four (16%) of 25 cases were Epstein-Barr virus positive (EBV+) (2/2 extranodal natural killer/T-cell lymphoma, 1/13 PTCL-NOS, and 1/4 angioimmunoblastic T-cell lymphoma with EBV+ immunoblasts). Two (15%) of 13 patients with PTCL-NOS were human immunodeficiency virus positive. No cases with evaluable DNA (0/15) were HTLV-1 positive, and 9 of 10 showed clonal TCRG rearrangements.

CONCLUSIONS

In comparison to Western studies, PTCLs from SSA show similar subtype distribution and male predominance but a younger age at diagnosis. Appropriate diagnosis of PTCL requires extensive ancillary testing not readily available in low-income countries, including much of SSA.

Distinct pattern of lymphoid neoplasms characterizations according to the WHO classification (2016) and prevalence of associated Epstein-Barr virus infection in Nigeria population

Background

The present study aimed to classify lymphoid neoplasms according to the latest World Health Organization (WHO) classification and outlining the distribution in Nigeria of different entities. Additionally, the study describes the prevalence of lymphoid neoplasms associated with Epstein-Barr virus (EBV) infection in the Nigerian population.

Methods

We collected 152 formalin-fixed paraffin-embedded (FFPE) tissues diagnosed as lymphoma from 2008 to 2018, coming from three different institutions located within three geopolitical zone in Nigeria. These institutions included the University College Hospital (UCH), Ibadan, Oyo State, the Enugu State University of Science and Technology Teaching Hospital (ESUTH), Enugu, Enugu State, and the Meena Histopathology and Cytology Laboratory (MHCL), Jos, Plateau State.

Results

From the total 152 cases retrieved, 50 were excluded due to insufficient tissue materials or inconclusive antigen reactivity. We confirmed 66 (64.7%) cases as lymphomas out of the remaining 102 FFPE with a male to female ratio of 2:1 and a mean age of 44.4 years. Ten entities were identified, and of these, chronic lymphocytic leukemia (CLL) was the most prevalent category (34.8%). For the diffuse large B-cell lymphomas not otherwise specified (DLBCL, NOS), the germinal centre B–cell type was the most common (71.4%). Ten lymphoma cases (15.2%) were positive for Epstein-Barr virus (EBV), most of which were Hodgkin lymphoma (HL). CLL was common in the Hausa ethnic group, HL in the Yoruba ethnic group, while the Igbo ethnic group had an equal distribution of CLL, HL, and DLBCL diagnosis.

Conclusion

Although the distribution of lymphomas in Nigeria shares some similarities with those of other countries, we described distinct features of some subtypes of lymphomas. Also, the study underscores the need for a more precise diagnosis and classification of lymphoid neoplasms in Nigeria using the latest WHO classification.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13027-021-00378-z.