Metachronous bilateral breast metastases of a lung neuroendocrine tumor: A case report

Abstract

Breast metastases of primary lung neuroendocrine tumors are rarely reported. The current report presents the case of a 41-year old female with no history of smoking who initially underwent surgery for a breast fibroadenoma, during which a neuroendocrine tumor of the right lung was detected via chest X-ray. The patient underwent surgery for the tumor and developed right breast nodules after adjuvant chemotherapy. Histological and immunohistochemical examinations of biopsies from these nodules indicated breast metastasis of the primary lung neuroendocrine tumor. The patient underwent mastectomy of the right breast but subsequently developed metastases in the left breast, for which local radiotherapy was administered. The observed metachronous bilateral breast metastases indicated that the contralateral breast should be considered during an investigation of metastasis.

Keywords: breast metastases; lung neuroendocrine tumor; metastatic cancer.

Figure 1

Chest computed tomography revealed nodules on the right lung, leading to a diagnosis of primary lung cancer.

Figure 2

Photomicrographs of tumor sections. (A) Hematoxylin and eosin staining of the surgically excised lung lesion (magnification, x400). (C) Immunohistochemistry of the tumor cells revealed CD56 (magnification, x400) and (E) synaptophysin positivity (magnification, x200). (B) Hematoxylin and eosin staining of a biopsy specimen from the right breast (magnification, x100). (D) Immunohistochemistry also revealed tumor cells that were positive for CD56 (magnification, x200) and (F) synaptophysin (magnification, x100).

Figure 3

Magnetic resonance imaging revealed nodules (red arrows) in the right breast.

Figure 4

Chest computed tomography revealed nodules (red arrows) in the left breast.