Tissue marking clip for stereotactic breast biopsy: initial placement accuracy, long-term stability, and usefulness as a guide for wire localization.
OBJECTIVE
To determine initial placement accuracy, long-term stability, and usefulness as a guide for wire localization for metallic marker clips placed percutaneously after stereotactic breast biopsy.


METHODS
One hundred forty-nine marker clips were placed percutaneously with a straight-needle or through-probe method, and clip positions were measured. The locations of 31 marker clips were followed up from deployment to first follow-up mammography. Thirty-six biopsy sites with marker clips were excised surgically and examined; 18 of these marker clips were targets for wire localization. The locations of 22 benign lesions were measured over time to calibrate the measurement system.


RESULTS
Baseline variability was 8 mm. Initial marker clip deployment averaged 5 mm above baseline from the center of the target lesion (P < or = .01). Compared with baseline variability, marker clips remained in place from initial deployment to first imaging follow-up (mean, 8.6 months). Potentially clinically meaningful misplacement rates (deployment > 24 mm from target lesion center) were 7% for the through-probe method and 11% for the straight-needle method (not significantly different; P = .33).


CONCLUSIONS
The marker clips appear to be useful targets for wire localization when the entire target lesion is removed at directional, vacuum-assisted breast biopsy. Upright, two-view mammography is recommended after deployment of the marker clip to document location.
Burbank
F
F
Mission Breast Care Center, Mission Viejo, CA 92691, USA.
Forcier
N
N
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle / Q000295:instrumentation* / Q000379:methods; D001940:Breast / Q000473:pathology*; D001943:Breast Neoplasms / Q000175:diagnosis / Q000601:surgery; D005260:Female; D006801:Humans; D008875:Middle Aged; D013238:Stereotaxic Techniques / Q000295:instrumentation*; D013396:Suction; D013525:Surgical Instruments