Pretreatment MR Imaging Features of Triple-Negative Breast Cancer: Association with Response to Neoadjuvant Chemotherapy and Recurrence-Free Survival.

Purpose To investigate whether pretreatment breast magnetic resonance (MR) imaging features are associated with pathologic complete response (PCR) and recurrence-free survival after neoadjuvant chemotherapy (NAC) in patients with triple-negative breast cancer. Materials and Methods Identified were 132 patients with primary triple-negative breast cancers who underwent NAC and pretreatment MR imaging between 2004 and 2010. Three breast radiologists independently reviewed the MR images based on the 2013 Breast Imaging Reporting and Data System lexicon. Presence of intratumoral high signal intensity and peritumoral edema on T2-weighted images was also evaluated. Association of PCR and recurrence-free survival with MR imaging features was assessed by using logistic regression and Cox regression. Bonferroni correction was applied to the P values. Results Among 132 patients, 18 (14%) underwent PCR. Round or oval masses (odds ratio, 3.5 [95% confidence interval: 1.3, 9.7]; P = .02), the absence of intratumoral T2 high signal intensity (odds ratio, 3.8 [95% confidence interval: 1.3, 11.0]; P = .01), and the absence of peritumoral edema (odds ratio, 3.4 [95% confidence interval: 1.2, 9.5]; P = .02) were associated with PCR, but not significantly. After 54 months of median follow-up, there were 41 (31% [41 of 132]) breast cancer recurrences. Peritumoral edema was the only significant variable associated with worse recurrence-free survival (hazard ratio, 4.9 [95% confidence interval: 1.9, 12.6]; P = .001). Conclusion Pretreatment MR imaging features may be associated with PCR and recurrence-free survival in patients with triple-negative breast cancer. © RSNA, 2016 Online supplemental material is available for this article.