Prostaglandin-mediated hypercalcemia in transitional cell carcinoma of the bladder

A patient with known transitional cell carcinoma of the bladder and hypercalcemia was evaluated for urinary prostaglandin levels when no bone metastases or elevated parathormone levels could be demonstrated. Urinary levels of prostaglandin E metabolite were assessed in relation to serum and urinary calcium levels during treatment. The serum calcium levels decreased from the 13.0 mg. per cent range whenever the rpimary tumor was manipulated (transurethral resection) or when other treatments directed at the tumor were used (radiation therapy and chemotherapy). Serum and urinary calcium levels, and urinary prostaglandin E metabolite decreased when 3 gm. aspirin were given daily. These data suggest that the somewhat unusual hypercalcemia in our patient was caused by a prostaglandin-secreting transitional cell carcinoma. Prostaglandin-secreting tumors are reviewed herein.