US-guided implantation of metallic markers for permanent localization of the tumor bed in patients with breast cancer who undergo preoperative chemotherapy.

Metallic markers were implanted with ultrasonographic guidance in 51 malignant breast tumors in 49 patients to tag the tumor bed in anticipation of complete or almost complete response to preoperative neoadjuvant induction chemotherapy before breast-conservation surgery. The markers were the only remaining evidence of the original tumor site in 47% (23 of 49) of the patients preoperatively. This technique effectively addresses the problem of preoperative localization of the tumor bed in complete or nearly complete response of breast cancer to neoadjuvant chemotherapy.