case report of metastatic invasive breast lobular carcinoma to the urinary bladder

breast cancer is the most common cancer in women except skin cancer. the common metastatic sites include lymph node, lung, liver and bone. however, metastasis to the bladder is extremely rare. to our knowledge, this is the first case of breast cancer metastasis to urinary bladder in jordan which is reported. nine years after the initial diagnosis of lobular breast carcinoma, the patient suffered from left side leg edema; ultrasonography and computed tomography scanning showed thickening of posterior bladder wall and bilateral hydronephrosis. the biopsy of the bladder confirmed metastatic lesion from the breast. in contrast to the primary tumor, bladder metastasis showed negative expression of estrogen (er) and progesterone (pr) receptors. however, her2neu test was negative in both. the reported case confirms that bladder metastasis from breast cancer tend to occur late after the diagnosis of the primary tumor. furthermore, bladder metastasis can be asymptomatic and heterogeneous in er and pr expression in comparison with the primary tumor. this report supports the need for careful follow-up and early intervention whenever such clinical situation is suspected. this report supports further evaluation of receptor status at time of metastasis.