The negative effect of triple-negative breast cancer on outcome after breast-conserving therapy

To evaluate disease failure patterns and overall survival (OS) of women with triple-negative (TN) breast cancer who underwent breast-conserving therapy (BCT) and to understand the relationship of TN tumors with other prognostic factors.

The Surveillance, Epidemiology, and End Results (SEER) registry identified 562 women diagnosed and/or treated with unilateral invasive breast cancer during 2003-2004 at three Emory hospitals. After medical record review, 193 eligible women, with all tumor types, received BCT. Primary endpoints (local, regional, and distant recurrences) and secondary endpoint (OS) were evaluated using chi-square tests and Cox proportional hazards models.

Of the 193 women, 33 (17.1%) had TN tumors and 160 (82.9%) had non-TN tumors. Patient characteristics were similar between the two tumor types; however, tumor grade and use of chemotherapy and hormones differed between the two groups. Median follow-up was 3.4 years; 22 patients had recurrence (12.2%), and 12 died (6.2%). Patients with TN tumors had higher local (12% versus 4% for non-TN) and distant recurrences (15% versus 4% for non-TN) rates (p = 0.01). On multivariate survival analyses, TN status [hazard ratio (HR) 1.8, 95% confidence interval (CI) 1.13-2.93] and African American (AA) race (HR 1.9, 95%CI 1.2-3.07) were independent predictors of inferior OS.

Patients with TN breast cancer showed significant increases in local and distant metastatic recurrence rates after BCT, and TN status and AA race were independent negative predictors of survival. For the future, identification of these high risk features may bring personalized medicine closer to reality.