Technique and results of localization biopsy in a breast screening programme

The techniques of ultrasonographic and hookwire localization biopsy of impalpable breast lesions detected by a large breast screening unit during its first year of operation are described. Hookwire localization (HL) was performed using mammography. Ultrasonographic localization (UL) was used for lesions readily detectable by ultrasonography by marking the skin directly over the lesion and calculating its depth below the surface. UL is not appropriate when microcalcification is the sole mammographic abnormality. Localization was required for 150 of the 191 (78.5 per cent) screen-detected lesions. HL was used for 94 (62.7 per cent) and UL for 56 (37.3 per cent). Four lesions were missed by HL, none by UL; 35 per cent of lesions removed by HL and 39 per cent by UL were malignant, giving benign: malignant biopsy ratios of 1.8:1 and 1.5:1 respectively. Only 22 percent of the patients required overnight hospital stay. Localization biopsy plays a major role in the surgery for screen-detected lesions and, where applicable, UL is the technique of choice.