Severe, diffuse osteosclerosis: A new manifestation of transitional cell carcinoma of the urinary bladder.

A 56 year-old man with a 2-year history of transitional-cell carcinoma of the urinary bladder presented with back pain and diffuse radiological osteosclerosis. Laboratory studies revealed borderline-low ionized serum calcium, and markedly elevated serum alkaline phosphatase (ALP) activity and serum osteocalcin. Serum acid phosphatase and prostatic-specific antigen (PSA) were normal. Serum 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D were just below the normal limit and parathyroid hormone was moderately elevated. A transiliac bone biopsy specimen revealed expanded bone trabeculae, abundance of osteoid-covered surfaces, and heavy metastatic spread. To the best of our knowledge, this is the first description of the association of osteosclerosis and metastatic transitional-cell carcinoma of the bladder.