Objectives: The purpose of this study was to evaluate the clinical importance and sonographic features of nonpalpable axillary lymphadenopathy identified on breast sonography in patients without malignancy.
Methods: Our study included 71 women and 2 men (mean age, 47.5 years; range, 16-69 years) with axillary lymphadenopathy identified on breast sonography. None of the 73 patients had known malignancy or presented with palpable lymph nodes or symptoms of mastitis. The lesions were pathologically diagnosed in 53 patients by surgical biopsy (n = 8), ultrasound-guided core needle biopsy (n = 17), or ultrasound -guided fine needle aspiration (n = 28). Twenty patients underwent follow-up imaging for 6 to 60 months (mean, 17 months). The sonographic features of the axillary lymph nodes were analyzed for all patients.
Results: The final diagnoses included benign reactive hyperplasia (n = 45), Kikuchi disease (n = 4), tuberculosis (n = 3), and sarcoidosis (n = 1). None of the 20 patients who underwent follow-up imaging developed malignancy. Suspicious sonographic features were frequently observed (loss of the fatty hilum, round shape, abnormal cortical thickening, and marked hypoechogenicity: 79.5%, 75.3%, 82.1%, and 9.6%, respectively) and were mostly complex, with the most common combination being a round shape and loss of the fatty hilum in 61.6% patients.
Conclusions: No malignancy was detected in all 73 patients, despite frequent manifestations of complex and extremely suspicious sonographic features. Short-term follow-up imaging rather than immediate biopsy can be recommended for nonpalpable lymphadenopathy in patients without known malignancy.
Keywords: axilla; breast; breast ultrasound; lymphadenopathy; sonography.
© 2015 by the American Institute of Ultrasound in Medicine.