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AIMS The aim of this study was to review the clinicopathologic characteristics of metastatic non-hematopoietic malignancies to the breast, in order to identify salient features for practicing pathologist that are useful in distinguishing metastatic lesions from primary breast neoplasms. METHODS AND RESULTS A total of 238 cases were identified during the period from January 2005 to January 2015. Clinicopathologic features of these cases were retrospectively reviewed. Primary tumors included melanoma (99, 42%), serous carcinoma (35, 15%), neuroendocrine neoplasm (32, 13%), sarcoma (23, 10%), and adenocarcinoma from various organs (47, 20%), among others. Most metastases were unilateral (223, 94%) and unifocal (206, 87%), and were detected radiographically (167, 70%). Concurrent ipsilateral axillary metastasis occurred in 33 (14%) patients. Among 238 cases, 41 had metastatic disease to the breast concurrently or preceding the primary cancer diagnosis. Notable, in 39 (16%) cases, breast metastasis was the first clinical presentation of disease, and 16 (41%) of these cases were initially misdiagnosed as breast primaries. In contrast, with known history of non-mammary primary tumors, only 4 of 197 (2%) cases were misdiagnosed (p<0.0001). CONCLUSIONS Metastatic tumors share many overlapping features with breast primary carcinomas. However, cases with a well-circumscribed tumor, lack of in situ component, ER/PR negativity, and unusual morphologic features should raise the consideration of metastatic disease. While clinical history is paramount for correct diagnosis, metastasis to the breast as the first clinical presentation is not uncommon.