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.