Local recurrence of breast cancer in the stereotactic core needle biopsy site: case reports and review of the literature.

Early mammographic detection of nonpalpable breast lesions has led to the increasing use of stereotactic core biopsies for tissue diagnosis. Tumor seeding the needle tract is a theorectical concern; the incidence and clinical significance of this potential complication are unknown. We report three cases of subcutaneous breast cancer recurrence at the stereotactic biopsy site after definitive treatment of the primary breast tumor. Two cases were clinically evident and relevant; the third was detected in the preclinical, microscopic state. All three patients underwent multiple passes during stereotactic large-core biopsies (14 gauge needle) followed by modified radical mastectomy. Two patients developed a subcutaneous recurrence at the site of the previous biopsy 12 and 17 months later; one had excision of the skin and dermis at the time of mastectomy revealing tumor cells locally. In summary, clinically relevant recurrence from tumor cells seeding the needle tract is reported in two patients after definitive surgical therapy (without adjuvant radiation therapy). Often, the biopsy site is outside the boundaries of surgical resection. Since the core needle biopsy exit site represents a potential area of malignant seeding and subsequent tumor recurrence, we recommend excising the stereotactic core biopsy tract at the time of definitive surgical resection of the primary tumor.