Information on the residual disease or positive axillary nodes after NAC is beneficial for the determination of the axillary surgical management and for the need of radiation therapy [7]. The guidelines define low tumor burden in the axilla as nodal disease that is image-detected disease not apparent on clinical examination; however, the imaging test is not specified in the guidelines. If there is pathological response to NAC and the patient is clinically node-negative, SLNB is preferred over ALND in order to minimize morbidity. In a study of 925 patients treated with NAC, 5-year overall survival was superior for patients with pathologic complete remission of the cytological proven axillary lymph node metastases (93%) compared with those without complete response (72%) [110]. Imaging of the Axilla CT Chest, Abdomen, and Pelvis There are no relevant data to support the use of contrast-enhanced or noncontrast-enhanced CT to image the axilla after completion of NAC. Digital Breast Tomosynthesis Diagnostic There are no data to support the use of DBT to image the axilla after completion of NAC in patients with initial clinical node-positive disease pre-NAC and who have no clinical suspicion of disease progression or new axillary nodal disease. When comparing mammography to DBT, one prospective study of 51 stage II and III breast cancer patients reported that MRI and DBT outperformed mammography and whole-breast US in the prediction of pathologic complete response [113]. Unfortunately, this cannot be extrapolated to axillary nodal disease because DBT does not completely visualize the entire axilla. DBT may be useful in selected cases after NAC because it may identify response within a clipped node and provide a means for image guided localization [131]. FDG-PET/CT Skull Base to Mid-Thigh FDG-PET/CT is widely used to assess response to therapy, despite the lack of consensus on the criteria for determining response.
Imaging of the Axilla. Information on the residual disease or positive axillary nodes after NAC is beneficial for the determination of the axillary surgical management and for the need of radiation therapy [7]. The guidelines define low tumor burden in the axilla as nodal disease that is image-detected disease not apparent on clinical examination; however, the imaging test is not specified in the guidelines. If there is pathological response to NAC and the patient is clinically node-negative, SLNB is preferred over ALND in order to minimize morbidity. In a study of 925 patients treated with NAC, 5-year overall survival was superior for patients with pathologic complete remission of the cytological proven axillary lymph node metastases (93%) compared with those without complete response (72%) [110]. Imaging of the Axilla CT Chest, Abdomen, and Pelvis There are no relevant data to support the use of contrast-enhanced or noncontrast-enhanced CT to image the axilla after completion of NAC. Digital Breast Tomosynthesis Diagnostic There are no data to support the use of DBT to image the axilla after completion of NAC in patients with initial clinical node-positive disease pre-NAC and who have no clinical suspicion of disease progression or new axillary nodal disease. When comparing mammography to DBT, one prospective study of 51 stage II and III breast cancer patients reported that MRI and DBT outperformed mammography and whole-breast US in the prediction of pathologic complete response [113]. Unfortunately, this cannot be extrapolated to axillary nodal disease because DBT does not completely visualize the entire axilla. DBT may be useful in selected cases after NAC because it may identify response within a clipped node and provide a means for image guided localization [131]. FDG-PET/CT Skull Base to Mid-Thigh FDG-PET/CT is widely used to assess response to therapy, despite the lack of consensus on the criteria for determining response.