Your doctor will make a diagnosis of fibroadenoma by first conducting a standard breast examination to feel for any lumps and to assess if you have any other breast complications. After the initial assessment, your doctor will recommend a breast mammogram or ultrasound to reveal the location of any solid masses within your breasts. Other diagnostic tests include fine-needle aspiration and core needle biopsy. Fine-needle aspiration involves inserting a hair-like needle into the affected breast to draw fluid from the lump. Core needle biopsy uses a larger needle to extract small tissue samples which can be analyzed.