This study was conducted to assess the incidence and impact of additional findings from magnetic resonance imaging (MRI) on the workup of patients eligible for breast-conserving therapy (BCT) and to optimise the specificity of further workup by combining radiological reading with computerised analysis. One hundred and sixteen patients eligible for BCT underwent preoperative MRI where the gold standard was histology or follow-up (median 35 months, range 23-48). The incidence of additional findings and impact on treatment (wider excision/conversion to mastectomy) were assessed. The specificity of referral to further workup was also assessed without and with computerised analysis. Additional findings from MRI occurred in 41% of patients, requiring workup in 78%. In 22% the findings were malignant, causing change in treatment. Specificity was 33% (10/30) for radiological reading alone, and 97% (29/30) combined with computer analysis. Our findings show that additional findings preoperative MRI required workup in approximately one-third of patients and we suggest that combining radiological reading with computer analysis has the potential to accurately exclude benign lesions from further workup.