Hypocalcemia with bony metastases in prostate cancer.

A 65 year old man presented with a two-month history of low back pain and fatigue and urinary symptoms over the preceding month. He was found to have had a hepatomegaly & a large nodular prostate on rectal examination. Investigations revealed a normal full blood count and renal profile, raised alkaline phosphatase and Prostate Specific Antigen (PSA), and low serum Calcium. A bone scan was performed which revealed widespread bony metastases in the axial and appendicular skeleton resulting in a 'superscan', consistent with prostatic metastases. We recommend that calcium levels be checked in all patients with prostate cancer and metastatic bone disease as this may have a bearing on their symptoms and the use of bisphosphonate therapy.