How are fibroadenomas typically diagnosed?

Biopsy. An experienced surgeon can determine by examination and imaging if there is a fibroadenoma. The most definitive confirmation is to have a needle biopsy. This is performed as an outpatient procedure and results are back in 2-3 days. Fibroadenomas are benign without any potential to turn into cancer.
Ultrasound. A breast ultrasound followed by a biopsy will confirm the diagnosis.