Correlation of histologic grade with other clinicopathological parameters, intrinsic subtype, and patients' clinical outcome in Taiwanese women

Objective: This study aimed to reveal the relationships between histologic grade and other clinicopathologic parameters including intrinsic subtype in Taiwanese women with breast cancer. Methods: There were 1302 women diagnosed with breast cancer recruited for this study. Histologic grade was scored according to the Nottingham-modified Bloom-Richardson grading system. Results: Higher tumor grade was associated with larger tumor size (P = 0.021), a larger number of lymph node metastases (P = 0.001), advanced clinical stage (P = 0.010), higher human epithelial growth receptor-2 positivity (P <0.001), negative estrogen receptor and progesterone receptor (P <0.0001) status. Triple negative breast cancer (56.6%) and human epithelial growth receptor-2 (44.3%) subtypes were associated with more Grade III breast cancer in contrast to luminal A (22.3%) and B (29.9%) breast cancer. In multivariate Cox regression analysis for cancer-specific survival, histologic grade (hazard ratio = 1.78) was a significant prognostic factor. Conclusions: This study demonstrated that histologic grade is highly correlated with some valuable biomarkers and confirmed the significance of histologic grade in Taiwanese female breast cancers.