The principal indication for biopsy is the presence of clinically suspicious findings on physical examination or diagnostic studies. Studies may be sampled with fine needle aspiration (FNA) and cytologic evaluation. A better diagnosis is obtained with a core-cutting biopsy and histologic study. Asymmetric nodularity, architectural distortion, or suspicious patterns of microcalcifications may require excisional biopsy guided by wire localization. In general, a wide excisional biopsy with a clear margin of several millimeters of surrounding normal glandular tissue is planned. The placement of the incision is determined by the location of the lesion (Figure 3). If possible, incisions in the upper/inner quadrants should be avoided, as they are most visible. Circumareolar or inframammary incisions tend to give the best cosmetic result. Curvilinear incisions along Langer's lines may be used in most areas; however, some surgeons prefer radial incisions, especially in the medial breast. The incision should be kept small and placed over the lesion. The incision for a wire localization need not be placed about the entrance site of the wire, because most wires are flexible enough to be drawn through the skin and subcutaneous fat into an open biopsy site.