Abstract
Invasive breast carcinoma is the most common cancer among women worldwide. Increase in early detection of breast carcinoma by different diagnostic modalities led to decrease in cancer-related mortality and morbidity. Multiple factors and genes are implicated in breast cancer pathogenesis. Cyclin D1 is an important cell cycle regulatory protein involved in carcinogenesis of various human cancers including breast cancer. Aims of the present study were to evaluate the prognostic importance of cyclin D1 expression in invasive breast carcinoma and its correlation with other prognostic and predictive factors. Patients undergoing mastectomy for breast carcinoma were selected from January 2016 to June 2017 in a tertiary care hospital. Clinical history including demographic parameters was collected in the study pro forma. Immunohistochemical staining for ER, PgR, HER2 and cyclin D1 was performed on all cases. The clinicopathological parameters like age, tumour size, histologic grade, histological type, lymphovascular invasion, axillary lymph node metastasis, ER, PgR and HER2 status were compared and correlated with cyclin D1 expression. Cyclin D1 expression found in 60% cases of breast carcinoma. Expression of cyclin D1 showed a highly significant correlation with histological grade (p = 0.000). Cyclin D1 expression showed significant correlation (p = 0.000) with molecular subtypes. There was also significant correlation between cyclin D1 expression and ER (p = 0.000) and PgR (p = 0.010) status. This study revealed significant cyclin D1 expression in low grade, well-differentiated breast cancer. Therefore, we found cyclin D1 as a favourable prognostic marker in breast carcinoma.