Evaluation of Waxing and Waning Axillary Lymphadenopathy in Females

Etiology and Differential Diagnosis

• Benign reactive processes (infectious, inflammatory, and autoimmune conditions) are the most common cause of waxing‑and‑waning axillary lymphadenopathy in females, but systematic evaluation is required to exclude lymphoma, which can present with fluctuating nodes. 1
• Bilateral axillary lymphadenopathy is a clue toward systemic disease, most commonly lymphoma, leukemia, or autoimmune disorders, and only rarely indicates bilateral breast cancer. 1

Malignant Contributions

• Metastatic breast cancer accounts for approximately 26 % of axillary lymphadenopathy cases; fewer than 1 % of breast cancers initially present solely as isolated axillary adenopathy. 2

Diagnostic Imaging Strategy

• Axillary ultrasound is the cornerstone initial imaging test for evaluating node morphology—including cortical thickness, hilum integrity, shape, and vascularity. 2
• Fluorodeoxyglucose PET/CT should not be used as the first‑line imaging modality for an isolated axillary mass of unknown cause, because it provides no diagnostic advantage over ultrasound. 2