Histological Phenotype of Breast Cancer in Indigenous Malawian Women Presenting at Queen Elizabeth Central Hospital in Malawi
Background: Breast cancer is the most commonly diagnosed cancer in women and the second leading cause of death of women in Africa. Management of breast cancer depends on availability of robust clinical and pathologic prognostic and predictive factors to guide decision making and the choice of treatment options.
Objective: We set out to determine the common histological phenotypes of breast cancer in indigenous Malawian women presenting at Queen Elizabeth Central Hospital (QECH).
Methods: We analyzed 63 samples of breast cancer Formalinfixed paraffin-embedded (FFPE) tissues and determined the prevalence of breast cancer over the three year period. Histological phenotypes were matched for age, tumor grade and clinical signs at presentation. The pathology files were retrieved from January 2012 through December 2013 and January through December 2015. Sixty-three breast cancer cases were analyzed for our results showed an increase in the prevalence of breast cancer from 2012 to 2015 as follows 2012 (22/99) 22.2%, 2013 (25/66) 37.9% and 2015 (16/48) 33.3%. Data was analyzed using IBM SPSS® version 20.0 for windows. The chi-square statistical test was used and a p-value of equal to or less than 0.05 was used to indicate statistical significance of the results
Results: The histological phenotypes were categorized as follows, invasive ductal carcinoma (IDC) 26 (41.3%), lobular carcinoma 17 (27%), Lobular plus ductal 4 (6.3%), medullary carcinoma 5(7.9%) and papillary intra ductal carcinoma 3(4.8%). Rare breast cancers were 1.6% each with the following proportions, clear cell carcinoma1, Paget disease and squamous cell carcinoma of surface origin1, invasive micro papillary carcinoma 1, oncocytic carcinoma1, solitary myeloma 1, malignant mesenchymal tumor 1, nonkeratinizing squamous cell carcinoma of surface origin plus Ductal carcinoma in situ 1(DCIS) and signet ring variety of mucinous carcinoma1. The common histological grade were grade 2, 32 (50.8%), grade 1,22 (34.9%) and grade 3,4 (6.4%), 5 (7.9%) cases could not be graded
Conclusion: The commonest histological phenotype of breast cancer was invasive ductal carcinoma (IDC) followed by lobular carcinoma, and grade two was the commonest histological grade followed by grade one. Most affected age groups were below 50 years of age with a peak at 41 to 50 years of age