Minimally Invasive Complete Response Assessment of the Breast After Neoadjuvant Systemic Therapy for Early Breast Cancer (MICRA trial): Interim Analysis of a Multicenter Observational Cohort Study

This prospective multicentre trial investigated the accuracy of ultrasound-guided biopsies identifying breast pathologically complete response (pCR) after neoadjuvant systemic therapy (NST) in patients with radiological partial (rPR) or complete (rCR) on MRI. Eight ultrasound-guided 14-G core biopsies were obtained before surgery close to the marker clip. Pre-surgical biopsies were obtained in 167 patients (136 rCR / 31 rPR) who had hormone receptor positive/HER2 negative (38%), HER2 positive (38%), or triple negative (36%) breast cancer. The pCR rate was 53% in the entire cohort. Of 78 patients who had residual disease, biopsies were false negative in 29 patients (37%). the multivariable significantly associated with false negative biopsy was rCR (FNR 47%; p=0.01)

Classifications: Adjuvant & Neoadjuvant Treatment

Keywords: Systemic therapy Trials