Relationship between Age, Histologic Grade, Tumour Size, Immunohistochemical Biomarkers Expressions and Molecular Subtypes of Invasive Breast Carcinoma in Ilorin, Nigeria

Abstract

Background: Background: Invasive breast carcinoma causes the most cancer-related death in women, and age is an essential non-modifiable risk factor. This study determined the relationship between age and histopathologic grade, tumor size, immunohistochemical biomarkers (ER, PR, and HER-2) expressions, and subtypes of invasive breast carcinoma. Methods: This was a retrospective hospital-based study of patients with prior histopathological diagnoses of invasive breast carcinoma. Relevant data, including age, histologic type, grade, tumor size, and hormonal receptor status, were retrieved from the archival pathology request forms. Results: The mean age of study subjects was 52.14 ± 12.14 years. The peak age group was in the 5th decade, accounting for 37.0 (32.7%) cases. Nottingham grade III invasive breast carcinoma accounted for 47 (41.6 %) cases and predominated in the 6th decade, accounting for 17 (50.0%) cases. Majority of the study subjects presented with tumor size greater than 5.0 cm (75.9%). The mean tumor size was 6.87 ± 3.20 cm and ranged from 3.2 cm to 16.0 cm. The immunohistochemical expressions of ER, PR, and HER-2 biomarkers were 36.3%, 28.3%, and 41.6%, respectively, particularly in the 5th and 6th decades. Also, Luminal A, Luminal B, Triplenegative, and HER-2 enriched subtypes occurred in 16.8%, 20.4%, 42.4%, and 20.4% cases respectively in the 5th and 6th decades. However, the triple-negative subtype was found in the 4th to 6th decades in equal proportions. Conclusion: This study observed triple-negative invasive breast carcinoma immunohistochemical subtypes with age association from the 4th to 6th decade