Stereotactic vacuum-assisted breast biopsy for suspicious microcalcifications: indications of clip deployment and reasons of clip dislocation

Abstract

Objective To analyze the indications of clip deployment and influencing factors for clip dislocation immediately after stereotactic vacuum-assisted breast biopsy. Methods One hundred and fourteen microcalcifications in 108 women aged 35 to 85 years old (median 63 years) underwent 11-gauge stereotactic vacuum-assisted breast biopsy. Every lesion was marked on biopsy site with Gel Mark Ultra clips (n = 82) or MicroMark Ⅱ clips ( n = 32) after biopsy. All microcalcifications were classified 3 mono-focal groups: 20 mm and one muhi-focal group according to its diameter and distribution. The distances between clips and biopsy sites were directly measured on post-biopsy craniocaudal and mediolateral mammograms. The distance was recorded as 20 mm. Results 88% (22/25) of mono-focal microcalcifications smaller than 10 mm and 70% (14/20) of mono-focal microcalcifications measured 10--20 mm were completely removed on mammograms, whereas none of mono-focal microcalcifications larger than 20 mm (n = 17) was completely removed. 65.8% (75/114) of the clips were accurately located. Thirty-nine clips were dislocated on at least one projection with 87.2% (34/39) of the clips dislocated only along the needle track, which is called effect. Hematoma was found in 4 patients, and the clip was accurately localized only in one case with hematoma, Conclusions Clips should be deployed as a standard procedure for mono-focal microcalcifications smaller than 20 mm and all multi-focal mierocalcifications. The major reasons for clip dislocation immediately after biopsy are the accordion effect and hematoma. Key words: Breast ; Calcinosis ; Biopsy, needle