title: Breast metastasis from lung cancer: a report of two cases and literature review.
abstract: Breast metastasis from extra-mammary malignancy is rare. An incidence of 0.4% to 1.3% has been reported in literature. The primary malignancies that most commonly metastasize to the breast are leukemia, lymphoma, and malignant melanoma. In this report, two cases of pulmonary metastasis to the breast were presented. A 40-year-old female manifested a right breast mass of 2-month duration. After physical examination was performed, a poorly defined mass was noted in the upper outer quadrant of the right breast. Another 49-year-old female manifested right breast mass of 5-day duration. A poorly defined mass was noted in the lower inner quadrant of the right breast. Mammography results also revealed breast cancer. The patients underwent local excision. After histological and immunohistochemical analyses were conducted, a primary lung carcinoma that metastasized to the breast was diagnosed. An accurate differentiation of metastasis to the breast from primary breast cancer is very important because the treatment and prognosis of the two differ significantly.
authors.affiliation: Department of Breast Cancer Pathology and Research Laboratory; Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education; Key Laboratory of Cancer Prevention and Therapy, Tianjin; Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Tianjin 30060, China.
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Breast Cancer Pathology and Research Laboratory; Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education; Key Laboratory of Cancer Prevention and Therapy, Tianjin; Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Tianjin 30060, China.
authors.forename: Shu-Ling
authors.initials: SL
authors.lastname: Wang
authors.affiliation: Department of Breast Cancer Pathology and Research Laboratory; Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education; Key Laboratory of Cancer Prevention and Therapy, Tianjin; Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Tianjin 30060, China.
authors.forename: Hong-Hong
authors.initials: HH
authors.lastname: Shen
authors.affiliation: Department of Breast Cancer Pathology and Research Laboratory; Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education; Key Laboratory of Cancer Prevention and Therapy, Tianjin; Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Tianjin 30060, China.
authors.forename: Feng-Ting
authors.initials: FT
authors.lastname: Niu
authors.affiliation: Department of Breast Cancer Pathology and Research Laboratory; Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education; Key Laboratory of Cancer Prevention and Therapy, Tianjin; Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Tianjin 30060, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Niu
keywords: Lung cancer; breast metastasis; immunohistochemistry; thyroid transcription factor-1 (TTF1)