Association between Gene Expression, Clinical Factors and Survival in Patients with Breast Cancer

Abstract

Breast cancer is the most frequently diagnosed and second cause of cancer deaths among women. A number of genes are found to be signicantly responsible for developing breast cancer. When healthy, these genes act as tumor suppressors by producing a protein that prevents cells from growing uncontrollably. But with mutations and other disorders in these genes, cells grow quickly and tumors form. In previous research it has been shown that higher risk of developing breast cancer is associated with having a number of gene mutation, but there are insucient discussions on the combined eect of both clinical factors and genetic information. Data for this study is taken from The Cancer Genome Atlas (TCGA) project on breast cancer cases. Overall survival time after diagnosis of breast cancer is considered as the outcome variable. A Cox Proportional Hazard regression model is applied for the survival analysis with both clinical factors and genetic information. Statistically signicant clinical factors and genes affecting patients survival are presented. Patients with the clinical variables of increasing age, premenopausal status, prior history of cancer and neoplasm status with tumor, Black or African American race and stage IIIA have signicantly more risk of failure (death) from breast cancer. In addition, we found signicant dierence in survival time between altered and non-altered cases of BRCA2, FOXA1, MLH1, RAD50 and RAD51C genes from both independent and combined analysis.