Correlation of Clinicopathological Features of Breast Cancer with Molecular Subtypes Taking Ki-67 into Consideration: Single Institution Experience Over 5 Years

Abstract

Background: Molecular classification of breast cancer is commonly done to determine response to therapy and cancer prognosis. Aim of the study was to compare prevalence of molecular subtypes of breast cancer in our institute using immunohistochemistry, including Ki-67, and correlate it with clinical and pathological prognostic factors.

Results: 300 cases of invasive breast cancer were included in the study. Average age at time of diagnosis was 44 years and average size of tumor was 3.4cms. Invasive ductal carcinoma was the most common histological type (75.3%). The most common molecular subtype was triple negative (34.3%) followed by Luminal B (33.4%), luminal A (17%) and Her-2 positive (15.3%). Large size and poorly differentiated tumors were predominantly triple negative tumors while lymph node metastasis was most commonly seen in Her-2 positive tumors.

Conclusion: Molecular subtype of breast carcinoma should routinely be done for all cases of carcinoma breast as it allows to identify aggressive tumors and target therapy accordingly.

Keywords: Breast neoplasm; Ki-67; immunohistochemistry; mastectomy.