Track Seeding in a Breast Cancer Patient after a 14-Gauge Core Needle Biopsy: A Case Report

and nonpalpable breast lesions is a safe and effective alternative to fine-needle aspiration and needle-localized breast excisional biopsies (1, 2). It can reduce the need for a two-stage procedure and can improve the surgical and oncological outcomes (3). However, one disadvantage of this technique for sampling breast cancer is the possible seeding of malignant tumor cells along the needle track (4-6). Many studies have examined track seeding after needle localization or biopsy, and they have reported microscopic seeding after procedures or recurrences at biopsy sites after definitive treatment (5-8). Yet to the best of our knowledge, gross track seeding after a 14-gauge core needle biopsy has never been reported for a breast cancer patient. We report here on a case of cancer cell seeding along the biopsy tract of mucinous carcinoma observed 70 days after performing a 14-gauge core needle biopsy.