Predicting invasion in mammographically detected microcalcification

AIM: To identify pre-operative factors which predict presence of invasive disease within mammographically detected malignant microcalcification. MATERIALS AND METHODS: A retrospective analysis was undertaken of 116 serial stereotactic core needle biopsies (SCNBs) performed on malignant mammographic calcification. Final surgical pathology was correlated with pre-operative features (clinical, radiological and core histology) in an attempt to predict the presence of an invasive component. RESULTS: Thirty-eight clusters contained invasive carcinoma. The sensitivity of SCNB for invasion was 55%. Clinical features, calcium morphology and cluster size were not shown to be predictive of invasive disease. Ductal carcinoma in situ (DCIS) of high grade on core histology and increasing number of calcifications were predictive of increased risk of invasion (high grade core biopsy DCIS and > 40 calcifications 48% invasive at surgical histology; high grade core biopsy DCIS and < 40 calcifications 15% invasive; non-high grade core biopsy DCIS 0% invasive). CONCLUSIONS: Identification of those clusters diagnosed as DCIS by percutaneous biopsy which are likely to harbour an invasive component is possible. It would seem reasonable to consider staging the axilla at therapeutic surgery in these patients. (C) 2001 The Royal College of Radiologists.