Assessing the prognostic utility of TCGA breast cancer dataset

Besides skin cancer, breast cancer is the most common type of malignancy among women in the United States and the second most common cause of cancer death in this population group. As with many other types of cancer, breast cancer is not equally distributed across the US population, with Whites presenting higher incidence and survival rates compared to African American women. A better understanding of the clinical and molecular factors associated with breast cancer and their distribution in the different racial/ethnic groups may provide further insight in the prognosis and treatment decisions of breast cancer. The Cancer Genome Atlas (TCGA) project provides publically available clinical data for more than 1000 patients with breast invasive carcinoma. However, the prognostic power of the TCGA breast cancer data in predicting breast cancer patient survival remains questionable. Therefore, the purpose of this study was to gain a better understanding of the clinical characteristics of the TCGA breast cancer data and evaluate the extent to which these data are suitable to analyze the relationship between survival outcomes with cancer mutations.;Using the clinical and follow-up TCGA breast cancer data, the tumor characteristics of 998 women diagnosed with breast cancer between 1988 and 2013 were compared by race/ethnicity. The study population consisted of four different racial/ethnic groups, including Not Hispanic Whites, Not Hispanic Blacks, Not Hispanic Asians and Hispanic women. Survival analysis was performed to evaluate the effect of certain risk factors in the survival of patients with breast cancer. Outcomes regarding the distribution of tumor and patient characteristics obtained from the analysis of the TCGA breast cancer data were compared to the Surveillance, Epidemiology and End Results Program (SEER) findings to identify whether the TCGA population used in this study is representative for each cancer population. Furthermore, overall survival as calculated for the TCGA study population was compared to the 5-year relative survival based on the SEER findings. Finally, power calculations were performed to assess the prognostic power of the TCGA breast cancer data.;In general, the results of our study regarding the distribution of several tumor characteristics in the four different racial/ethnic groups match those provided by the SEER program. However, in contrast to numerous studies indicating that Black women present poorer survival rates compared to Whites, our findings suggest that there is no significant difference in the 5-year survival of breast cancer between Not Hispanic White and Not Hispanic Black women.