Pattern of distribution of Hodgkin lymphoma and non-Hodgkin lymphoma subtypes among adults: An experience of a Nigerian tertiary health facility

Objective: Lymphomas are a heterogeneous group of malignancies with varying geographic and demographic distributions. This study aimed to describe the pattern of distribution of Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL) subtypes among adults. Methods: This was a retrospective study of patients diagnosed with lymphoma at our institution between January 2019 and December 2023. Data were extracted from the record of the histopathology department of the institution. Lymphoma subtypes were classified according to the World Health Organisation (WHO) classification. Results: There were 59 cases of lymphoma during the study period, made up of 30 (50.8%) males and 29 (49.2%) females. The overall mean age at diagnosis was 45±18 years. HL accounted for 35.6% (21/59) of the cases, while NHL accounted for 64.4% (38/59) of the cases. Among the HL, classical HL contributed 85.7% while Nodular lymphocyte-predominant HL contributed 14.3%. The distribution of the different histologic subtypes of HL showed mixed cellularity 10 (47.6%) as the commonest subtype, followed by nodular sclerosis 5 (23.8%) subtype. Among the NHL, B-cell lymphoma accounted for 76.3% while T-cell lymphoma accounted for 23.7%. Overall, Small Lymphocytic Lymphoma (SLL)/ Chronic Lymphocytic Leukaemia (CLL) was the commonest subtype and accounted for 42,1% (16/38), followed by diffuse large B-cell lymphoma (DLBCL) 18.5% (7/38), and follicular lymphoma (FL) 7.9% (4/38). Conclusion: This study provides insight into the distribution pattern of lymphoma subtypes among adults in our environment, with mixed cellularity as the most common HL histologic subtype and SLL/CLL as the predominant NHL subtype.