Breast core biopsy reporting categories--An internal validation in a series of 3054 consecutive lesions.

We reviewed 3226 consecutive core biopsies (CBs) of 3054 mammographically detected breast lesions performed at our Centre from November 1993 to June 2003. CB diagnoses, classified according to the Non-operative Diagnosis Subgroup of the British National Health Service Breast Cancer Screening Programme (NHSBSP), were B5 (37.1%), B4 (0.5%), B3 (7.6%), B2 (50.9%) and B1 (3.9%). It was necessary to repeat the procedure in 172 cases (5.3%). The values for absolute sensitivity and specificity are 90.8% and 83.8%, respectively. The positive predictive value for categories B4 and B5 is 100%, with no false-positives. The positive predictive value for category B3 is 16.3%. The negative predictive value for B2 category is 97.2%, with a false-negative rate of 3.5%. In conclusion, this system of analysis has enabled us to confirm that our CB results surpass the minimum recommended standards proposed by the NHSBSP.