Case 11 Answer 2

Surgical excision is recommended for core needle biopsies yielding atypia. In about a third of cases, DCIS is found at excision after ADH is found at needle biopsy [Jackman, et. al., Radiology, 1999, Brem et. al, AJR, 1999]. With a core biopsy we are only sampling a portion of the area. The degree of underestimation of disease of core needle biopsy has been shown to improve (upstaging to DCIS at surgery is less common) when vacuum-assisted core needle devices (ie. Mammotome) are used [Joshi, et. al, Breast Journal, 2001]. These devices allow a larger sample to be obtained. Studies have shown that this also improves with a higher # of samples taken [Jackman et. al., Radiology, 2001] (this is why we usually obtain 12 samples instead of 3 or 6.)