However, there was correlation between mammographic size and surgical pathology in only 60% of cases [45]. One study found that if >50% of the margin of the primary lesion was mammographically visible at baseline, posttreatment mammographic imaging was a reliable tool for determining lesion size [28,46]. In a study of 56 patients, mammography was 79% sensitive and 77% specific in predicting residual disease after therapy, performing better than clinical breast examination [47]. The extent of calcifications on mammography after therapy does not correlate well with residual tumor burden and is overestimated in up to 45% of patients [48-50]. Therefore, it is not a reliable marker of remaining viable tumor. In a study including 139 patients with baseline mammographic calcifications, residual calcifications were present 7 Monitoring Response to Neoadjuvant Chemotherapy on all posttreatment mammograms [45]. ER-positive tumors are more likely than ER-negative tumors to have residual malignant calcifications on mammography after treatment, whereas triple-negative tumors are the least likely to have residual malignant calcifications after therapy, suggesting that different tumor subtypes may warrant different approaches [48,51]. There is no relevant literature specifically comparing the performance of DBT to mammography after initiation of completion of NAC. MRI Breast Without and With IV Contrast MRI is a functional imaging technique that permits evaluation of a viable tumor before and after NAC by detecting changes in tumor vascularity [31]. There is substantial evidence to support the routine use of MRI to stage, monitor early response, and assess for residual and recurrent disease, given the overall high sensitivity and relatively high specificity of this technique [1]. However, MRI can overestimate as well as underestimate the amount of residual tumor after completion of therapy.
Monitoring Response to Neoadjuvant Systemic Therapy for Breast Cancer. However, there was correlation between mammographic size and surgical pathology in only 60% of cases [45]. One study found that if >50% of the margin of the primary lesion was mammographically visible at baseline, posttreatment mammographic imaging was a reliable tool for determining lesion size [28,46]. In a study of 56 patients, mammography was 79% sensitive and 77% specific in predicting residual disease after therapy, performing better than clinical breast examination [47]. The extent of calcifications on mammography after therapy does not correlate well with residual tumor burden and is overestimated in up to 45% of patients [48-50]. Therefore, it is not a reliable marker of remaining viable tumor. In a study including 139 patients with baseline mammographic calcifications, residual calcifications were present 7 Monitoring Response to Neoadjuvant Chemotherapy on all posttreatment mammograms [45]. ER-positive tumors are more likely than ER-negative tumors to have residual malignant calcifications on mammography after treatment, whereas triple-negative tumors are the least likely to have residual malignant calcifications after therapy, suggesting that different tumor subtypes may warrant different approaches [48,51]. There is no relevant literature specifically comparing the performance of DBT to mammography after initiation of completion of NAC. MRI Breast Without and With IV Contrast MRI is a functional imaging technique that permits evaluation of a viable tumor before and after NAC by detecting changes in tumor vascularity [31]. There is substantial evidence to support the routine use of MRI to stage, monitor early response, and assess for residual and recurrent disease, given the overall high sensitivity and relatively high specificity of this technique [1]. However, MRI can overestimate as well as underestimate the amount of residual tumor after completion of therapy.