CHARACTERIZATION OF BENIGN LESIONS AND CARCINOMAS OF THE FEMALE BREAST IN A SUB-SAHARAN AFRICAN POPULATION

Carcinoma of the breast is the second most frequent tumour in African females. Breast carcinomas in African females appear about a decade ea rlier and follow a more aggressive clinical course than those in devel oped countries. To elucidate this difference we investigated 63 biopsi ed benign lesions of the female breast for their potential to malignan t progression. We also performed histologic typing and grading of 184 female breast carcinomas received at the Muhimbili University Hospital in Dar es Salaam, Tanzania. Fibrocystic disease and fibroadenomas wer e the most frequent lesions. The majority of patients with fibrocystic disease had no proliferative lesion and thus were not at a significan tly increased risk of developing breast carcinomas. For fibroadenomas, no indication for precancerous lesions was found. The vast majority o f breast carcinomas investigated were invasive. As a striking feature, the majority of those studied (66%) were of the non-special type (NST ), displaying a more aggressive behaviour than the remaining tumours o f the special type (ST). In the group of ST tumours, cribriform types constituted 41% of the cases which may be a special feature of the car cinomas in African females. Among the NST, the tumours were either of grade II or grade III, whereas in ST, 25% of the cases were of grade I . Since histology observed in this study is comparable to that seen in patients from the Western society, late hospital presentation with ad vanced tumour stages may be a major reason for differences in clinical behaviour between African and Western females. A genetic factor, howe ver, may be an important contributing factor.