Abstract
Introduction: Breast cancer (BC) is the most frequently diagnosed malignancy (25% of all cancers) and the leading cause of cancer-related death in women; death is mainly attributed to the metastatic spread of the primary tumor. On the other hand, secondary tumors of the bladder are rare, representing 2% of all bladder neoplasms. Breast cancer rarely spreads to the urinary bladder. Patients in almost all previous reports have been diagnosed with BC several months before the bladder metastasis (BM) was discovered. Case Presentation: A 67-year-old woman presented with irritative bladder symptoms with no history suggestive of BC. Normal breast examination and normal laboratory investigations with Breast Imaging Reporting and Data System 1 (BI-RADS 1) in mammographic evaluation challenged the pathological findings of the bladder biopsy that was positive for metastatized BC to the bladder. Conclusions: Metastatic BC may rarely initially present with irritative lower urinary symptoms and absent clinical and radiological features of BC-but positive histopathological findings.