Radiographic appearance of an osseous metastasis to the distal radius from a transitional cell carcinoma of the urinary bladder

Abstract

An eight-year-old male entire springer spaniel diagnosed with transitional cell carcinoma (TCC) of the urinary bladder apex underwent partial, full-thickness cystectomy and the mass was excised completely with 1 cm of clear histological margins.Chemotherapy was initiated three months after surgery when ultrasound revealed probable early recurrence at the surgical site. Three doses of carboplatin were administered, but progressive disease was identified. Complete ultrasonographic response to vinblastine was noted after six treatments.Five months after commencing chemotherapy, a persistent right thoracic limb lameness was noted. Radiographs revealed a lesion on the distal right radius that, despite a smooth periosteal reaction, had subtle features of malignancy. Fine needle aspirates of the lesion were consistent with metastatic TCC, and the patient was euthanased. There was no detectable neoplasia elsewhere.