Breast cancer metastasis to urinary bladder related hematuria and concomitant venous thromboembolism—case report of a challenging clinical scenario

Abstract

: Breast cancer metastasis to the urinary bladder is uncommon and its true incidence may be underreported, requiring a high level of clinical suspicion to diagnose them. Venous thromboembolism (VTE) is a known complication in breast cancer and guidelines recommend treatment with the use of anticoagulation therapy unless contraindicated by active bleed or high bleeding risk. We present a rare case of 42-year-old female patient presenting with concurrent VTE and visible hematuria due to breast cancer metastasis to the urinary bladder. The patient initially underwent radical mastectomy and axillary lymph node dissection for high grade invasive ductal breast carcinoma (pT3N3cM0). Despite adjuvant radiotherapy, chemotherapy and hormonal therapy, the patient subsequently developed interval liver and bladder metastasis. She presented with right lower limb VTE 6 years after the initial mastectomy. The patient developed painless visible hematuria after starting anticoagulation therapy. Hence treatment of VTE was contraindicated and was managed instead with insertion of an inferior vena cava (IVC) filter. In the literature, breast cancer metastasis to the urinary bladder is rare, with 65 published to date. Our case report is unique as there was concomitant symptomatic VTE, thereby posing a clinical challenge of not being able to use anticoagulation therapy. We postulate that as the cancer specific and overall survival rates for breast cancer patients continues to improve, the incidence of patients presenting with metastasis to the urinary bladder may increase. Urinary bladder metastasis in breast cancer populations have variable presentations, requiring a high level of clinical suspicion. Prompt collaboration with urologists and pathologists is recommended in this group of patients who complaints of hematuria. Prognosis is usually poor and the optimal management is currently unknown.