Breast Cancer Biomarker Status and Histo-Pathologic Correlation in St. Paul Hospital Millennium Medical College, Addis Hiwot General Hospital and Onco-pathology Diagnostic Center, Addis Ababa, Ethiopia

Abstract

Abstract Background: By using immunohistochemical biomarker (estrogen receptor, progesterone receptor and human epidermal receptor-2) breast cancer is classified into 4 major molecular subtypes, namely luminal A, luminal B, triple negative and human epidermal receptor-2 overexpressing. Triple negative breast carcinoma is a heterogeneous group that includes tumors with good as well as bad prognosis. Luminal A tumors are the most common type, tend to have better prognosis. Triple negative and human epidermal receptor-2 overexpressing type breast carcinoma has the worst prognosis. Hormone receptor positive breast cancers are tend to be diagnosed in older patients, lower grade and stage compared to hormone receptor negative carcinomas. Objective: To study breast cancer immunohistochemical biomarker and histo-pathologic correlation at Saint Paul Hospital Millennium Medical College, Addis Hiwot General Hospital, and Onco-pathology cancer diagnostic center Addis Ababa, Ethiopia from July 2021 to July 2024. Materials and methods: A medical record review was conducted using data from the from October 2023 to October 2024 at St. Paul hospital millennium medical college, Addis Hiwot General Hospital and onco-pathology diagnostic center. Data was collected using data extraction checklist by data collectors and principal researcher from St. Paul Hospital millennium medical college patient charts, and data base of Addis Hiwot General Hospital and Onco-pathology Diagnostic Center. Data was analyzed by the SPSS version 27. Descriptive statistics like frequencies and cross tabulation were made for most selected variables. Chi square test and multinomial logistic regression analysis was used to assess the association between the dependent and independent variables. Results: Among the 490 breast cancer cases majority (68.18%) were below the age of 50 yrs. The most common histologic subtype was invasive carcinoma of NST(83.6%) followed by mixed carcinoma of invasive lobular and ductal carcinoma. Majority of cases were positive for ER (82.3%) and PR (72.8%) and 75.2% of cases were HER-2 negative. Luminal A accounts for 57.9% cases followed by luminal B (26.2%). Triple negative breast carcinoma was the least common subtype which accounted for 7.37%. Age, tumor size and Nottingham grade have II shown significant association with the intrinsic subtype of breast carcinomas. HER-2 positive breast cancer tends to occur in younger age and to have larger tumor size Conclusion: The mean age at diagnosis of breast cancer was 45 years. Invasive carcinoma of NST was the most common histologic subtype. Hormone receptor status expression was positive in majority of breast cancer cases. Luminal A was the most common intrinsic subtype whereas triple negative was the least. HER-2 positive breast cancer tends to occur in younger age and larger tumor size. Key words: Breast cancer, Histo-pathology, Hormone receptor, Breast biomarker