Uncommon high-risk lesions of the breast diagnosed at stereotactic core-needle biopsy: Clinical importance

PURPOSE: To assess the outcome of papillary lesions, radial scars, or lobul ar carcinoma in situ (LCIS) diagnosed at stereotactic core-needle biopsy (S CNB). MATERIALS AND METHODS: Retrospective review of 1,236 lesions sampled with S CNB yielded 22 papillary lesions, nine radial scars, and five LCIS lesions. Diffuse lesions such as papillomatosis, papillary ductal hyperplasia, papi llary ductal carcinoma in situ (DCIS), and atypical lobular hyperplasia wer e not included. The mammographic findings, associated histologic features, and outcome were assessed for each case. RESULTS: Sixteen papillary lesions were diagnosed as benign at SCNB. Of the se, five were benign at excision, and 10 were unremarkable at mammographic followup. At excision of an unusual lesion containing a microscopic papilla ry lesion, DCIS was found. Three of four papillary lesions suspicious at SC NB proved to be papillary carcinomas; the fourth had no residual carcinoma at excision. Eight of nine radial scars were excised, which revealed atypic al hyperplasia in four scars but no malignancies. One LCIS lesion was found at excision to contain DCIS. CONCLUSION: Benign or malignant papillary lesions were accurately diagnosed with SCNB in the majority of cases. Cases diagnosed as suspicious for mali gnancy or with atypia or unusual associated histologic findings should be e xcised. No malignancies were found at excision of radial scars diagnosed at SCNB. Surgical removal of these lesions following SCNB may not be routinel y necessary. DCIS was found in one lesion diagnosed as LCIS at SCNB, which suggests that removal of these lesions may be prudent.