The axilla is incompletely visualized on the mediolateral and lateral projections, thereby limiting the use of these modalities to reliably detect residual disease. FDG-PET/CT Skull Base to Mid-Thigh PET/CT is not routinely used to evaluate the axilla after completion of NAC. Although a few studies suggest that PET can reliably predict the response of axillary nodes early in treatment, a majority of studies show that PET has low sensitivity (63%) for detection of residual disease after NAC [112,135]. No imaging test can reliably detect residual nodal disease after NAC, and therefore surgical sampling is the standard of care. Mammography Diagnostic Although many patients undergo mammography or DBT after NAC, there is no specific evidence supporting its use in the imaging of known axillary lymph node-positive breast cancer after completion of therapy [4]. The axilla is incompletely visualized on the mediolateral and lateral projections, thereby limiting the use of these modalities to reliably detect residual disease. MRI Breast Without and With IV Contrast MRI is not routinely used for evaluation of the axilla after completion of NAC because it is only 38% to 61% sensitive for detecting residual axillary disease [112-114,120-122]. No imaging test can reliably detect residual nodal disease after NAC, and therefore surgical sampling is the standard of care. Use of MRI for restaging the axilla in clinically node-positive patients is questionable [4]. In a retrospective study of 135 clinically node-positive patients who underwent NAC, MRI evaluation of the axilla after treatment had a low NPV (26%) and therefore could not predict residual axillary disease when a positive MRI of the axilla was defined as node >1 cm, cortex >3 mm, loss of hilum, or irregular contour [121]. In a retrospective study of 269 node-positive patients, postchemotherapy MRI was only 38% sensitive, 76% specific, and 58% accurate in predicting the pathology result of the SLN.
Monitoring Response to Neoadjuvant Systemic Therapy for Breast Cancer. The axilla is incompletely visualized on the mediolateral and lateral projections, thereby limiting the use of these modalities to reliably detect residual disease. FDG-PET/CT Skull Base to Mid-Thigh PET/CT is not routinely used to evaluate the axilla after completion of NAC. Although a few studies suggest that PET can reliably predict the response of axillary nodes early in treatment, a majority of studies show that PET has low sensitivity (63%) for detection of residual disease after NAC [112,135]. No imaging test can reliably detect residual nodal disease after NAC, and therefore surgical sampling is the standard of care. Mammography Diagnostic Although many patients undergo mammography or DBT after NAC, there is no specific evidence supporting its use in the imaging of known axillary lymph node-positive breast cancer after completion of therapy [4]. The axilla is incompletely visualized on the mediolateral and lateral projections, thereby limiting the use of these modalities to reliably detect residual disease. MRI Breast Without and With IV Contrast MRI is not routinely used for evaluation of the axilla after completion of NAC because it is only 38% to 61% sensitive for detecting residual axillary disease [112-114,120-122]. No imaging test can reliably detect residual nodal disease after NAC, and therefore surgical sampling is the standard of care. Use of MRI for restaging the axilla in clinically node-positive patients is questionable [4]. In a retrospective study of 135 clinically node-positive patients who underwent NAC, MRI evaluation of the axilla after treatment had a low NPV (26%) and therefore could not predict residual axillary disease when a positive MRI of the axilla was defined as node >1 cm, cortex >3 mm, loss of hilum, or irregular contour [121]. In a retrospective study of 269 node-positive patients, postchemotherapy MRI was only 38% sensitive, 76% specific, and 58% accurate in predicting the pathology result of the SLN.