The pattern of prognostic and risk indicators among women with breast cancer undergoing modified radical mastectomy in Dar es Salaam, Tanzania

Amos R. Mwakigonja, Happiness Rabiel, Naboth A. Mbembati, Leonard E. K. Lema

Breast cancer is the commonest female malignancy globally and the second (after uterine cervix) in sub-Saharan Africa including Tanzania. Prognostic indicators reportedly influence post-mastectomy adjuvant therapy by predicting risks on survival and recurrence although in Tanzania this data is lacking. Here, we evaluate the pattern of prognostic and risk indicators among women with breast cancer undergoing modified-radical-mastectomy (MRM) at Muhimbili National Hospital (MNH) and Tumaini Hospital (TH), Dar es Salaam, Tanzania. This hospital-based prospective cross-sectional study included female patients undergoing MRM from April 2011 to January 2012. Clinical stage I-III patients were enrolled after being scheduled for mastectomy. Patients with evidence of distant metastasis (stage IV) were excluded. Mastectomy and axillary lymph nodes biopsies were submitted to the Histopathology laboratory for grade, type, nodal and margins status. Data was collected using a structured questionnaire and analyzed using SPSS. A total of 348 patients were admitted with breast cancer including 86 patients (with 16 from TH having similar demography and presentation) meeting inclusion criteria. Age-range at diagnosis was 28-79 years, mean 52.1 years. Most (89 %) attained menarche after 11 years. About 56 % were postmenopausal. The majority (78 %) were multiparous with positive family history in 14.1 and 37.6 % used hormonal contraceptives. About 27.1 % were social alcohol drinkers. The majority (61 %) had T4b disease, 75.6 % had positive axillary nodes including 42.7 % with 4-9 involved nodes (N2). The commonest (91.9 %) histological type was invasive ductal carcinoma. Lobular, medullary and mucinous carcinomas were rare. Most (83.7 %) of our patients presented with stage III and the rest stage II. Intermediate- and high-grade tumors accounted for 73.5 %. Following MRM, 25 % of our patients had positive surgical margins and similarly for the base. Most of our breast cancer patients present with frequent risks including younger age, multiparity, hormonal contraceptives use, alcohol use and family history. Unfavourable prognostic indicators including late stages, large primary tumor size, skin infiltration, positive surgical margins, positive axillary lymph nodes and a high histological grade were associated. A sustainable screening program by self-examination to allow early diagnosis is needed to reduce morbidity and mortality from this cancer.