PATHOLOGY RESEARCH AND PRACTICE © Gustav Fischer Verlag Characterisation of Benign Lesions and Carcinomas of the Female Breast in a Sub-Saharan African Population Martin P. Mbonde 1 , Hassan Amir 2 , Noah A. Mbembati 2 , Rolland Holland 3 , Reinhard Schwartz-Albiez 4 and James N. Kitinya 1 Departments of lpathology and 2Surgery, Muhimbili University College of Health Sciences, Dar es Salaam, Tanzania; 3Department of Pathology, University of Nijmegen, Nijmegen, The Netherlands; 4Tumor Immunology Programme, German Cancer Research Centre, Heidelberg, Germany Summary em females. A genetic factor, however, may be an im- portant contributing factor. Carcinoma of the breast is the second most frequent tu- mour in African females. Breast carcinomas in African females appear about a decade earlier and follow a more aggressive clinical course than those in developed countries. To elucidate this difference we investigated 63 biopsied benign lesions of the female breast for their potential to malignant progression. We also performed histologic typing and grading of 184 female breast car- cinomas received at the Muhimbili University Hospital in Dar es Salaam, Tanzania. Fibrocystic disease and fi- broadenomas were the most frequent lesions. The ma- jority of patients with fibrocystic disease had no prolif- erative lesion and thus were not at a significantly in- creased risk of developing breast carcinomas. For fibro- adenomas, no indication for precancerous lesions was found. The vast majority of breast carcinomas investi- gated 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 of 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 carci- nomas 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 differ- ences in clinical behaviour between African and West- Pathol. Res. Pract. 194: 623-629 (1998) Key words: Breast carcinoma - East Africa - Cancer progression - Benign lesions - Histopathology Introduction Carcinoma of the breast has, until recently, been the second most common malignancy in the African fe- male, preceded by carcinoma of the uterine cervix [1, 31]. Though AIDS associated Kaposi's sarcoma is cur- rently replacing breast cancer as the second most fre- quent malignancy in females in at least some areas of this region [44J, the importance of breast cancer has not diminished. A review of the Tanzania Cancer Registry, based at the Department of Pathology, Muhimbili Med- ical Centre, in Dar es Salaam for the years 1970-1985, carried out by the authors, indicated that this tumour type represented about 14% of all malignancies affect- ing the indigenous African female. The prevalence of this condition in the general population of Tanzania and of most sub-Saharan African countries varies from as low as 8% in Zimbabwe [l8J to as high as 34.5% in Sudan [l9J. Address for correspondence: Martin P Mbonde, Dept. of Pathology, Muhimbili University College of Health Sciences, PO.Box 65002, Dar es Salaam, Tanzania. 0344-0338/98/0194-0623$5.00/0