Mammography Diagnostic There is insufficient data to support the use of mammography as the initial imaging test for an axillary palpable mass, even though pathologically enlarged nodes may be seen as dense enlarged nodes or masses on the mediolateral or mediolateral-oblique projection of a mammogram. However, if there is a personal history of breast cancer or clinical suspicion of axillary tail breast carcinoma or metastatic adenopathy from a breast primary, then mammography as an adjunct test to axillary US can provide global assessment of the ipsilateral breast and identify other suspicious findings such as microcalcifications associated with the palpable mass. MRI Breast MRI of the breast is not routinely performed as the initial imaging assessment for a unilateral palpable axillary mass. MRI may be helpful in defining disease extent and characterizing the breast primary if axillary US reveals adenopathy of unknown primary malignancy and the mammogram is negative for a primary breast malignancy [34,35]. MRI can also help characterize the axillary mass by determining any adjacent vascular involvement, chest wall involvement, and involvement of other axillary structures. Sestamibi MBI There is no relevant literature to support the use of Tc-99m sestamibi molecular breast imaging (MBI) for assessing a unilateral palpable axillary mass. US Axilla Multiple studies support the use of US to characterize findings in the axilla [36,37]. The most common etiology, besides normal tissue, is adenopathy from benign or malignant disease, typically of lymphatic or mammary origin. In addition, accessory breast tissue and both benign and cancerous lesions within accessory tissue can be seen [36]. If a suspicious US finding or mass is identified, US-guided biopsy can be performed for definitive diagnosis, even if the malignancy rate may be low in a woman with palpable axillary mass and no other signs of malignancy [37].
Imaging of the Axilla. Mammography Diagnostic There is insufficient data to support the use of mammography as the initial imaging test for an axillary palpable mass, even though pathologically enlarged nodes may be seen as dense enlarged nodes or masses on the mediolateral or mediolateral-oblique projection of a mammogram. However, if there is a personal history of breast cancer or clinical suspicion of axillary tail breast carcinoma or metastatic adenopathy from a breast primary, then mammography as an adjunct test to axillary US can provide global assessment of the ipsilateral breast and identify other suspicious findings such as microcalcifications associated with the palpable mass. MRI Breast MRI of the breast is not routinely performed as the initial imaging assessment for a unilateral palpable axillary mass. MRI may be helpful in defining disease extent and characterizing the breast primary if axillary US reveals adenopathy of unknown primary malignancy and the mammogram is negative for a primary breast malignancy [34,35]. MRI can also help characterize the axillary mass by determining any adjacent vascular involvement, chest wall involvement, and involvement of other axillary structures. Sestamibi MBI There is no relevant literature to support the use of Tc-99m sestamibi molecular breast imaging (MBI) for assessing a unilateral palpable axillary mass. US Axilla Multiple studies support the use of US to characterize findings in the axilla [36,37]. The most common etiology, besides normal tissue, is adenopathy from benign or malignant disease, typically of lymphatic or mammary origin. In addition, accessory breast tissue and both benign and cancerous lesions within accessory tissue can be seen [36]. If a suspicious US finding or mass is identified, US-guided biopsy can be performed for definitive diagnosis, even if the malignancy rate may be low in a woman with palpable axillary mass and no other signs of malignancy [37].