Association of Cyclin D1 Expression and Histopathological Grading of Invasive Ductal Carcinoma Breast Cancer: An Observational Cross-Sectional Study in Surabaya

Breast cancer is ranked as the fifth major contributor to global cancer-related fatalities. Cyclin D1 is frequently overexpressed in cases of invasive ductal breast cancer and plays a specific role during the advanced stages of tumor evolution. However, the utilization of cyclin D1 overexpression as a predictive tool remains a subject of debate. This study aims to determine the relationship between cyclin D1 expression and the histopathological grading of invasive ductal carcinoma in breast cancer. The results can serve as scientific evidence that cyclin D1 can aid in predicting the prognosis of patients, making it a valuable tool in health facilities. In this cross-sectional study, employing flow cytometric techniques, cyclin D1 expression was assessed in 30 patients categorized as having grade 1, grade 2, or grade 3 invasive ductal breast cancer based on histopathological diagnoses. The analysis indicated a negligible difference in cyclin D1 expression levels between patients with invasive ductal breast cancer grades 1 and 2 (P = 0.283). In contrast, a statistically significant disparity in cyclin D1 expression was observed between patients diagnosed with grades 1 and 3 of invasive ductal breast cancer (P = 0.026), as well as between grades 2 and 3 (P = 0.026). Our findings underscore a moderate yet significant correlation between cyclin D1 expression and breast cancer grading (R: 0.508; P < 0.05). A moderate correlation between cyclin D1 expression and the histopathological grade of breast cancer was substantiated. These observations lend credence to the utilization of cyclin D1 as a marker indicative of an unfavorable prognosis.