A palpable breast mass is a common presenting symptom of breast cancer. Breast masses that are firm, immobile, irregularly shaped, and accompanied by lymphadenopathy, nipple discharge, or skin changes are concerning for malignancy. However, history and physical examination are not sufficient to diagnose or exclude malignancy, and further evaluation with imaging is required.
In women age ≥30 who have a palpable breast mass, the first step is mammography, followed by possible ultrasound, to characterize the mass and determine the need for biopsy. Patients with a palpable breast mass and benign radiographic features (eg, simple cyst on ultrasound) may not require further workup; those with other abnormal imaging findings require core needle biopsy to exclude malignancy. However, even palpable breast masses can be **mammographically and sonographically occult** (false negative rate as high as 30%), particularly in patients with dense breasts, and malignancy can be missed. Therefore, patients with palpable breast masses and negative imaging require percutaneous core needle biopsy.