Association of mammography and ultrasound features with MammaPrint in patients with estrogen receptor-positive, HER2-negative, node-positive invasive breast cancer

Background MammaPrint is a 70-gene signature microarray assay that predicts the likelihood of recurrence of breast cancer and chemotherapeutic benefits. Purpose To investigate the association between mammography and ultrasound (US) features and MammaPrint results in patients with estrogen receptor (ER)-positive, HER2-negative, node-positive invasive breast cancer, and to identify the predictive factors for high risk of recurrence. Material and Methods This retrospective study included 251 patients with ER-positive, HER2-negative, 1-3 node-positive invasive breast cancer. Mammography and US findings were reviewed according to the BI-RADS criteria. The association between MammaPrint results and the clinicopathological and imaging features was evaluated. Logistic regression analysis was performed to identify independent predictors for high risk of recurrence. Results Of the patients, 143 (57.0%) and 108 (43.0%) had low and high risks for recurrence on MammaPrint, respectively. Young age (odds ratio [OR] 1.08; 95% confidence interval (CI) 1.04-1.12; P<0.001), posterior enhancement on US (OR 2.45; 95% CI 1.16-5.20; P = 0.019), absence of posterior shadowing on US (OR 3.19; 95% CI 1.17-8.62; P = 0.023), high histologic grade (OR 113.36; 95% CI 6.79-1893.53; P = 0.001), and high Ki-67 level (OR 4.90; 95% CI 2.62-9.17; P<0.001) were independently associated with high risk of recurrence on multivariate logistic regression analysis. Conclusion Posterior features in US may predict a high risk of recurrence in patients with ER-positive, HER2-negative, node-positive invasive breast cancer, which may be useful in enhancing the diagnostic value of MammaPrint and aid in the decision-making process regarding treatment.