Metastatic Breast Lesion From Thymic Carcinoma

Metastases to the breast from other organs are not common. 1 Among lesions metastatic to the breast, carcinoma of the opposite breast, multicentric lymphoid malignancies, and disseminated melanoma constitute the most likely sources. 2 Thymic carcinoma is a rare malignant neoplasm representing 0.2% to 1.5% of all malignancies. 3 The incidence of distant metastasis from thymic carcinoma varies from 1.5% to 15.5%, and the tumor metastasizes most frequently to the liver, followed by the kidney and extrathoracic lymph nodes. 4 We present a case of thymic carcinoma metastatic to the breast. To our knowledge, this is the first report of thymic carcinoma metastatic to the breast.