The aim of this investigation was to study the efficacy of surgical therapy in patients with non-palpable ductal carcinoma in situ (DCIS) presenting as microcalcifications diagnosed by means of stereotactic large-core needle biopsy (SCNB). This is a retrospective study with a historical control group within a 12-year period. Two groups of consecutive patients diagnosed with DCIS (1991-2002) by means of needle-localised open breast biopsy (NLBB, n=49) and SCNB (n=51) were studied. Both groups were comparable for clinical, radiological and pathological characteristics. The therapeutic interval (time from presentation to definitive of therapy) was 62-days in the SCNB group versus 32-days in the NLBB group (p<0.001). In the SCNB group fewer surgical procedures were required for completion of surgical therapy (p=0.006) and after local excision the surgical margins were more often tumour free (p=0.002). It is postulated that the need for fewer surgical procedures and the greater frequency of tumour-free margins after local excision may be attributable to SCNB.