Abstract
Seeding of cancer cells along the needle tract during core needle biopsy is a well-known phenomenon, with a reported frequency of between 22 and 50% [Hoorntje et al. in Eur J Surg Oncol 30:520-525, 2004;Liebens et al. in Maturitas 62:113-123, 2009;Diaz et al. in AJR Am J Roentgenol 173:1303-1313, 1999;]. Local recurrence due to needle tract seeding is rare because the immune system eliminates the cancer cells in most cases. In addition, most local recurrences due to needle tract seeding occur as invasive carcinoma after diagnosis of invasive ductal carcinoma of the breast or mucinous carcinoma, and needle tract seeding due to noninvasive carcinoma is uncommon. We herein report a rare case of local breast cancer recurrence histologically resembling Paget disease, presumably due to needle tract seeding after core needle biopsy for diagnosis of ductal carcinoma in situ of the breast. After receiving a diagnosis of ductal carcinoma in situ, the patient underwent skin-sparing mastectomy and breast reconstruction with a latissimus dorsi musculocutaneous flap. The pathological study showed ER/PgR-negative ductal carcinoma in situ, and no postoperative radiation therapy or systemic therapy was administered. Six months after the surgery, the patient had a breast cancer recurrence histologically resembling Paget disease, presumably in the scar of her core needle biopsy. The pathological study showed Paget disease localized in the epidermis, no invasive carcinoma, and no lymph node metastasis. It was morphologically similar to the primary lesion and was diagnosed as a local recurrence due to needle tract seeding.