MRI appearances of the axilla in treated breast cancer

Differentiation between recurrent axillary disease and changes due to radio therapy or surgery has major implications for management in patients follow ing breast cancer treatment, but clinical examination of the axilla may be difficult. This study was undertaken to correlate the MRI appearances of th e axilla following breast cancer treatment with clinical outcome. 74 women with treated breast cancer were evaluated by MRI (0.5 T) and the appearance s defined by consensus. Outcome was assessed by long-term clinical follow-u p. 62 women had symptoms related to the axilla while 12 were scanned to sta ge the axilla. None of the axillary staging group had abnormal MRI appearan ces and none of these subsequently developed recurrence. The 62 symptomatic women were subdivided according to MRI appearances. 22 had normal axillary appearances, 18 had an axillary mass and 22 women had abnormal, axillary a ppearances (rated mild, moderate and severe) in the absence of a mass. Norm al axillary appearances on MRI excluded recurrent disease as the cause of s ymptoms with a specificity of 94.7% and a positive predictive value (PPV) o f 95.5%, The presence of an axillary mass was commonly but not exclusively due to recurrent disease (sensitivity 68.4%, specificity 88.4%, PPV 72.2%). Sensitivity for diagnosis of axillary recurrence was increased to 89.5% wi th a specificity of 76.7% if the criteria for recurrent disease were taken as either the presence of an axillary mass or severe axillary changes in th e absence of a mass lesion.