For 18 of these patients, ductal carcinoma in situ was the only finding at surgical excision. Four of these 31 patients with ductal carcinoma in situ on percutaneous biopsy were found to have invasive ductal carcinoma at surgical excision. Nine patients with ductal carcinoma in situ on percutaneous biopsy had no residual carcinoma found in the surgical specimen. All nine biopsies had been performed for microcalcifications, and all nine were ductal carcinoma in situ on pathologic examination. These results indicate that it is possible to completely remove small areas of ductal carcinoma in situ presenting as microcalcifications on mammography using a percutaneous vacuum-assisted biopsy instrument.
Complete removal is facilitated by small size on mammography and by taking more specimens.
In our experience, mammographic masses are not completely removed by percutaneous vacuum-assisted biopsy. Few studies have reported complete pathologic removal of breast malignancies with the percutaneous vacuum-assisted biopsy instrument, verified on surgical specimens. In none of these studies was the intent of the clinician to remove the entire lesion. Complete removal of mammographic lesions does not ensure complete pathologic excision of the malignancy. Among 15 malignancies diagnosed by core needle biopsy by Liberman and associates,7 the mammographic lesion was completely removed, yet 11 patients had residual tumor found at surgical excision.