2. A 47-year-old woman, gravida 2, para 2, recently discovered a small, firm, painless mass in her right breast during a self-examination. Two years ago, she had a fibroadenoma removed from her left breast. She has no family history of breast cancer. Examination of the breasts shows a 2x1-cm, firm, irregular, mobile mass at the 9-o’clock position in the right breast. No nipple discharge is noted. Needle aspiration of the mass is attempted, but no cellular material is obtained. Mammography shows normal findings. Which of the following is the most appropriate next step in the evaluation of this patient?