Malignant lymphomas in Jos, Nigeria: a ten-year study.

One hundred-and-sixty-seven cases of malignant lymphomas (ML) diagnosed in the Jos University Teaching Hospital, Jos, Nigeria, over a ten-year period (1979-88) were reviewed. The overall incidence rate is 13.4 per 100,000 with a median age of 29 years and a male:female ratio of 3:1. Non-Hodgkin's lymphoma (NHL) and Hodgkin's disease (HD) represent 67.7 pc and 32.3 pc cases respectively. Low, intermediate and high grade NHLs account for 51.4 pc, 17.7 pc and 30.0 pc of cases respectively; the collective median age at presentation is 31 years and the male:female ratio is 2:1 (Follicular: 13.3 pc; diffuse 86.7 pc). The small lymphocytic lymphoma is the commonest NHL (38.1 pc); the small non-cleaved cell type (African Burkitt's lymphoma type) accounts for 24.7 pc with an incidence rate of 2.2 per 100,000 within the general population and a median age of 10 years. Hodgkin's disease (median age: 28 years) is the commonest form of ML exhibiting only a single peak in the 21-30 years range. The male:female ratio is 8:1 and histological types associated with poor prognosis predominate. The prevalent clinical presentations is with a painless peripheral lymphadenopathy, the cervical group of lymph nodes is often involved representing 55 pc and 67 pc of NHL and HD cases respectively. Burkitt's lymphoma present primarily as an abdomino-pelvic tumour (67.8 pc of cases). Primary extradonal presentation is seen in 90 pc of MLs, all of which are the NHL group with Burkitt's lymphoma accounting for 80 pc of all cases.