Correlation Between Receptor Status And The Presence Of Axillary Lymph Node Metastasis In Breast Cancer In Kenyatta National Hospital

Abstract

Background: Breast cancer is the second most common malignancy in Kenyan women. Breast cancer survival is linked to early detection, timely and appropriate treatment. Furthermore, survival is dependent on stage and biological behaviour of the tumour. Expression of hormonal receptors by breast cancer cells is one of the key factors in the management of this disease because of its impact on metastatic spread, recurrence, disease free survival and overall survival. It however remains unclear how different molecular subtypes of breast cancer impact on axillary node involvement. Objective: This study seeks to determine the correlation between expression of hormonal receptors, Human epidermal growth factor receptor-2 and Ki-67 protein in breast cancer with that of axillary lymph node status in breast carcinoma. Methodology: This was a prospective cross sectional study carried out over 9 months at Kenyatta National Hospital (KNH) surgical wards and histopathology laboratory. Using a consecutive sampling method, patients with a histological diagnosis of breast cancer and scheduled to undergo a modified radical mastectomy (MRM) were recruited. Data collected included age at diagnosis, parity, menopausal status, clinical examination findings, stage of the disease clinically and pathologically and hormonal receptor status. Data was managed using MS Excel and analyzed using SPSS version 21.0. Continuous data is presented as means and categorical variables as proportions. All statistical tests were conducted at 5% level of significance. The data is presented in form of tables, bar charts and pie charts. Results: The results of this study show that the most common molecular subtype of breast cancer in Kenyan women who present at the Kenyatta National Hospital for treatment is Luminal A followed by TNBC. Luminal A disease was spread almost evenly across all age groups while TNBC disease was most commonly diagnosed in younger premenopausal women. In this study most patients presented with T3 disease with a higher number of them being Luminal A followed by TNBC disease which were prevalent across all T size stages. Luminal A disease has the highest number of lymph node positive disease tumours but TNBC and HER-2 enriched disease have a higher propensity for nodal involvement in breast cancer. However, our study shows no correlation between hormonal receptor positivity or negativity and expression of HER-2 or lack of it, and nodal status in invasive breast cancer.