Distribution of Breast Cancer Subtypes Among Nigerian Women and Correlation to the Risk Factors and Clinicopathological Characteristics

BACKGROUND: Breast cancer in African women differs from the Caucasian. Understanding the profile of Nigerian women with breast cancer will help with preventive measures and treatment. This study focused on the clinico-pathological characteristics, with risk factors of breast cancer patients in Nigeria. METHODS: Newly diagnosed female patients with breast cancer were assessed over 12 months. Patients were reviewed using a predesigned proforma which focused on socio-demographic information, clinical information, risk factors and tumor biology. RESULTS: A total of 251 women were identified; their mean age was 46 years. More than half (62.5%) are premenopausal at presentation, 37.8% with Eastern Cooperative Oncology Group (ECOG) score of 0 and right side (50.2%) as the most common primary site of disease. Less than half of them (43.0%) are estrogen receptor (ER) positive, 27.9% are progesterone receptor (PR) positive, 43.8% and 47.4% are hormone receptor positive and triple negative, respectively. Most patients presented at the latter stage of the disease, stage III (66.9%) and stage IV (18.3%). Only 15.9% are well differentiated and almost all (92.8%) had invasive ductal histological type. Obesity (66.2%) and physical inactivity (41.9%) are the most common risk factors for the disease. A significant relationship was found between immunohistochemistry status and family history of breast cancer, tumor site, previous breast surgery, previous lump and alcohol intake. CONCLUSION: Findings from this study showed that Nigerian breast cancer patients differ from their counterparts in the high human development index (H-HDI) countries in terms of the patients and disease characteristics. In view of this, prevention and treatment options should consider this uniqueness to ensure better outcome.