Immunophenotypic classification of lymphoblastic leukaemia and lymphocytic lymphoma--an experience in the south-western area of the Cape Province of South Africa.

Adequate tumour material was obtained for phenotypic classification using a standard library of monoclonal antibodies from 81 previously untreated patients with acute lymphoblastic leukaemia (ALL), chronic lymphocytic leukaemia (CLL), or lymphocytic lymphoma (LL). Sixty-one individuals were adults and 20 were children of 14 yr or younger. Fifty-eight of the patients (72%) had acute lymphoblastic leukaemia and the remaining 23 (28%) had chronic lymphocytic leukaemia or lymphocytic lymphoma. Considering only the patients with acute lymphoblastic leukaemia (n = 58) the median age was 19 yr (range 3-69 yr): 9% were black, 43% were coloured, 48% were white, and the distribution between adult (n = 38) and paediatric patients (n = 20) was comparable. Complete remission rate in the adults was 58% and in the paediatric group 85%. For the total group (n = 58) median duration of survival was 59 weeks for common, 39 weeks for null, 63 weeks for T-ALL, and 13 weeks for B-ALL subtypes. In both the common and the null groups overall and disease-free survival was superior in the children. In contrast, no difference was evident in the T-ALL group, which was also notable for its high incidence in young coloured males. The 15 patients with CLL and eight with LL were adults and all the cells were phenotypically of B lineage: in view of the small numbers no comments are possible about ethnic differences. A multi-centre collaborative study is needed to define the epidemiology of haematologic malignancy in South Africa, with emphasis on differences among ethnically distinct subpopulations.