A female patient presented with a hard, mobile lump in her right breast. Which investigation would be most helpful in making on diagnosis:

Large-needle (core needle) biopsy removes a core of tissue with a large cutting needle and is the diagnostic procedure of choice for both palpable and image-detected abnormalities. Core biopsy has the advantage that tumor markers, such as estrogen receptor (ER), progesterone receptor (PR) and HER2 overexpression can be performed on cores of tissue. Ref: Giuliano A.E., Hurvitz S.A. (2013). Chapter 17. Breast Disorders. In M.A. Papadakis, S.J. McPhee, M.W. Rabow, T.G. Berger (Eds), CURRENT Medical Diagnosis & Treatment 2014.