Sestamibi MBI There is no relevant literature supporting the use of Tc-99m sestamibi MBI for staging of the axilla in clinically node-positive breast cancer patients. US Axilla Axillary US is typically performed for assessing nodal disease in patients with newly diagnosed breast carcinoma and palpable adenopathy [7,92]. In a retrospective series of 1,287 breast cancer patients who had preoperative axillary US-FNA followed by SLNB or ALND, the group with axillary US-FNA had a higher number of metastatic axillary lymph nodes than those with micro- or macrometastatic nodal disease on SLNB. This suggests that patients with US visible nodal disease, confirmed by axillary US-FNA, have more extensive nodal involvement [60]. Positive axillary US, confirmed with biopsy, helps to identify patients with higher tumor burden [54,55], and as such, these patients can proceed directly to ALND. However, axillary US is not able to detect all metastatic nodes and therefore cannot replace SLNB or ALND [58]. It is well known that negative axillary US with or without biopsy does not rule out nodal disease [58]. The sensitivity of US-guided biopsy also has variable sensitivity ranging from 52% to 90%, whereas the specificity is higher, ranging from 98% to 100% [59-63]. For many cases, axillary US can differentiate patients with high lymph node tumor burden from patients with low lymph node tumor burden, suggesting that those with positive axillary nodes on percutaneous biopsy should have ALND rather than SLNB, especially because the Z0011 criteria do not apply to patients with clinically palpable adenopathy. Axillary US features favoring nodal metastases include cortical thickness of >0.3 cm and absence of a fatty hilum, a finding with a high positive predictive value (PPV) of 90% to 93% [103-105]. CT Chest, Abdomen, and Pelvis CT allows assessment of the axillary level II and III nodal regions that are not always well visualized on US.
Imaging of the Axilla. Sestamibi MBI There is no relevant literature supporting the use of Tc-99m sestamibi MBI for staging of the axilla in clinically node-positive breast cancer patients. US Axilla Axillary US is typically performed for assessing nodal disease in patients with newly diagnosed breast carcinoma and palpable adenopathy [7,92]. In a retrospective series of 1,287 breast cancer patients who had preoperative axillary US-FNA followed by SLNB or ALND, the group with axillary US-FNA had a higher number of metastatic axillary lymph nodes than those with micro- or macrometastatic nodal disease on SLNB. This suggests that patients with US visible nodal disease, confirmed by axillary US-FNA, have more extensive nodal involvement [60]. Positive axillary US, confirmed with biopsy, helps to identify patients with higher tumor burden [54,55], and as such, these patients can proceed directly to ALND. However, axillary US is not able to detect all metastatic nodes and therefore cannot replace SLNB or ALND [58]. It is well known that negative axillary US with or without biopsy does not rule out nodal disease [58]. The sensitivity of US-guided biopsy also has variable sensitivity ranging from 52% to 90%, whereas the specificity is higher, ranging from 98% to 100% [59-63]. For many cases, axillary US can differentiate patients with high lymph node tumor burden from patients with low lymph node tumor burden, suggesting that those with positive axillary nodes on percutaneous biopsy should have ALND rather than SLNB, especially because the Z0011 criteria do not apply to patients with clinically palpable adenopathy. Axillary US features favoring nodal metastases include cortical thickness of >0.3 cm and absence of a fatty hilum, a finding with a high positive predictive value (PPV) of 90% to 93% [103-105]. CT Chest, Abdomen, and Pelvis CT allows assessment of the axillary level II and III nodal regions that are not always well visualized on US.