THE EPIDEMIOLOGY OF HAEMATOLOGICAL MALIGNANCIES AT THE UNIVERSITY OF BENIN TEACHING HOSPITAL: A TEN YEAR RETROSPECTIVE STUDY (JANUARY 1999-DECEMBER 2008)

Abstract

Background: Haematological malignancies comprise a collection of heterogeneous
malignant conditions, all originating from cells of the bone marrow and the lymphatic
system. They are a major cause of morbidity and mortality in the Niger delta region of
Nigeria. A region noted for its high petrochemical activities. The burden of these
malignancies has not been critically evaluated in this region. There are also limited
numbers of studies on the epidemiology of these malignancies in this country. These
were the motivations for my research into this area.
Objective: The objective of this study was to determine the epidemiology of
haematological malignancies, in terms of age, sex, marital status, educational
background, occupation, tribe, residence, and place of origin of the patients and to
determine the incidence, prevalence and the clinico-pathological profile of the various
tumor types in the study area.
Materials and methods: A total of four hundred and twelve (412) case notes of all
patients with the diagnosis of haematological malignancies over a ten-year period
(January 1999 to December 2008) were reviewed. Demographic features and clinico
pathological profile of the patients were extracted and analyzed using the SPSS version
15.
Results: Result showed that haematological malignancies accounted for 17.4% of all
malignancies seen in the study area. Haematological malignancies were significantly
more common in males, adults, married, educated, unemployed patients and the Bini
tribe.
The average incidence rate of haematological malignancies in the study area was 41.2
persons per year. Non-Hodgkin’s lymphoma (NHL) (33.5%) was found to be the most
common haematological malignancy in the study area. It was followed by chronic
lymphoid leukaemia (CLL) (17.0%), chronic myeloid leukaemia (CML) (9.5%), Burkitt’s
lymphoma (BL) (8.7%), acute lymphoblastic leukaemia (ALL) (8.3%), multiple myeloma
(MM) (8.2%), Hodgkin’s lymphoma (HL) (5.8%), acute myeloid leukaemia (AML)
(4.9%) myelofibrosis (MF) (2.7%). The least prevalent was polycythaemia rubra vera
(PRV) (1.4%).
Weakness, fever, weight loss, lymphadenopathy, bone pain, hepatomegaly and
splenomegaly were the frequent clinical features noted in these patients. Weakness was
very common in those patients with ALL, AML, CLL, CML and MM, while weight loss
occurred more in patients with chronic leukaemia and in patients with lymphoma.
Haematocrit was reduced below the reference ranges in all the malignancies except in
PRV where it was elevated. White blood cell count was moderately elevated (mean of
55×109/l) in the acute leukaemias but markedly increased (mean of 148×109/l) in
chronic leukaemia. Male patients had higher haematocrit, white cell count, and platelet
count at presentation than the female patients.
Conclusion: Haematological malignancies are common in the study area. They were
high in adults, males, the married, the educated, the unemployed and the Bini tribe.
Place of origin and area of residence were not identified as risk factors for
haematological malignancies. Weakness and anaemia were found to be the commonest
symptom and sign of haematological malignancies in the study area. Except for
polycythaemia patients, most of the patients had low haematocrit and low platelet
count which were severe in acute leukaemias compared to the chronic leukaemias and
the lymphomas.

THE EPIDEMIOLOGY OF HAEMATOLOGICAL MALIGNANCIES AT THE UNIVERSITY OF BENIN TEACHING HOSPITAL: A TEN YEAR RETROSPECTIVE STUDY (JANUARY 1999-DECEMBER 2008)