Abstract

Background: The current markers Ki-67 and p53 are well-known indicators of the aggressiveness of the tumour biology in a multitude of tumours characterized by less and different drivers and are poorly coordinated with the clinicopathologic presentation of Triple-Negative Breast Carcinoma (TNBC). In this study, the expression of Ki-67 and p53, and their relationship with other clinicopathological parameters was analysed. Methods: A total of 120 breast cancers were histologically confirmed triple-negative BCs from which 5 were excluded due to missing data.In this cross-sectional study, 120 breast cancers were included and 5 missing data excluded among histologically confirmed triple-negative BCs. The immunohistochemical expression of Ki-67 labelling index and p53 has been analysed and correlated with: age, tumour size, histological tumour grade, nodal status, stage at diagnosis, lymphovascular invasion, and histological tumour type. Independent predictors of nodal involvement were evaluated by a multivariable logistic regression. Results: High expression of ki 67(>20%) was observed in 85.0% and abnormal expression of p53 in 49.2% of the tumours. High ki-67, tumour size (p = 0.029), histological grade (p<0.001) and nodal involvement (p<0.001) and stage (p = 0.001) were found to correlate significantly with each other. Grade (p<0.001), nodal involvement (p<0.001) and stage (p = 0.025) were significantly related to aberrant p53. Ki-67 levels increased in tumours with aberration in p53. Nodal invasion was independently predicted by both the Ki-67 (OR = 1.49 per 10% increase) and aberrant p53 (OR = 2.66). Conclusions: Ki-67 and p53 are shown to give complementary information regarding aggressive clinicopathological characteristics of triple negative breast carcinoma, and can contribute to pathological risk stratification, especially for nodal involvement.

Keywords: Triple-negative breast cancer, Ki-67, p53, Immunohistochemistry, Lymphnode