Excisional biopsy of impalpable soft tissue tumors. US-guided preoperative localization in 12 cases.

We present a technique to facilitate excisional biopsy of impalpable soft tissue tumors. A modified Kopans localization needle is positioned preoperatively under ultrasound-guidance (7.5 MHz). The needle contains a hookwire with an over-bent hook that springs open when protruded beyond the needle tip and anchors the wire in the lesion. The technique was used in 12 patients and facilitated excisional biopsy in all of them.