Secretory carcinoma of the breast: A case report.

INTRODUCTION: Secretory breast carcinoma (SBC) is a rare breast tumor which accounts for < 0.15% of all breast cancers. It was originally described as a juvenile breast carcinoma, occurring in young children and adolescent women. SBC is associated with a characteristic balanced translocation, t(12;15), that creates aETV6-NTRK3 gene fusion.

PRESENTATION OF CASE: A 52-year-old Caucasian woman had palpable lump in her right breast. After breast imaging examination (BI-RADS 4b) and preoperative core-needle biopsy with suspicion of SBC a breast conserving therapy was performed. The diagnosis of SBC was confirmed through immunohistochemistry and cytogenetic examination of the tumor. The patient is now 22 months post‑surgery and remains disease‑free.

DISCUSSION: Recent studies reported that the disease occurs at a later age than previously recognized, and is associated with good long-term survival. In breast imaging it may mimic a benign tumor. Immunohistochemistry and cytogenetic analysis of the tumor are crucial for confirmation of SBC.

CONCLUSION: There is no consensus with regard to the best treatment strategy for patients with SBC. Breast conserving therapy with sentinel lymph nodes biopsy is at present the first choice treatment. Further research for a specific NTRK3 tyrosine kinase inhibitor could lead to the discovery of a new targeted treatment of this tumor.