Factors that impact the upgrading of atypical ductal hyperplasia.

PURPOSE: The purpose of this study was to identify the factors that may have an impact on upgrading atypical ductal hyperplasia (ADH) lesions to malignancy. MATERIALS AND METHODS: Between February 1999 and December 2010, the records of 150 ADH lesions that had been biopsied were retrospectively reviewed. The biopsy types included 11-gauge stereotactic vacuum-assisted biopsy (SVAB) (n=102) and ultrasonography (US)-guided 14-gauge automated biopsy (n=48). The patients were divided into two groups: those who had cancer in the final pathology and those who did not. Variables associated with underestimation of ADH lesions were compared between the groups. RESULTS: The underestimation rates according to the biopsy types were 41.7% (20/48) for the US-guided 14-gauge automated biopsy and 20.6% (21/102) for the 11-gauge SVAB (P = 0.007). The rate of underestimation was significantly higher in lesions greater than 7 mm than it was in smaller lesions, with both US-guided 14-gauge automated biopsy and 11-gauge SVAB (P = 0.024 and P = 0.042, respectively). The rate of underestimation was significantly higher with the 11-gauge SVAB (P = 0.025) in lesions that were suspicious (R4) and highly suggestive of malignancy (R5) than in those that were probably benign (R3). CONCLUSION: The underestimation rate in ADH lesions was significantly higher with US-guided 14-gauge automated biopsy compared to the 11-gauge SVAB. The underestimation rate was also significantly higher in lesions greater than 7 mm regardless of the biopsy type, and in lesions biopsied using SVAB that were regarded as suspicious (R4) or highly suggestive of malignancy (R5) on imaging.