Breast metastasis from signet ring cell carcinoma of the urinary bladder: A case report

Carcinoma of the bladder metastatic to the breast is only sporadically reported in the literature. To the best of our knowledge, the present report is the first described case of signet ring cell carcinoma of the urinary bladder metastasizing to the breast. The patient was a 43-year-old woman who underwent transurethral partial cystectomy for signet ring cell carcinoma of the urinary bladder and adjuvant chemotherapy with cisplatin and gemcitabine. At 7 months postcystectomy, the patient presented with a solitary nodule in the right breast. Following transdermic core needle puncture biopsy of the lesion and histological examination, the tumor was found to be composed of signet ring cells, which were similar to the cells in the original cystectomy specimen. The patient underwent mastectomy without further chemotherapy and has remained free from metastasis to other organs during 1 year follow-up.