Extensive bone metastases in a patient with prostatic adenocarcinoma and normal serum prostate-specific antigen and prostatic acid phosphatase.

A 49-year-old man was hospitalized because of severe back pain and weight loss for 2 months. Because the serum carcinoembryonic antigen (CEA) level was elevated to 37.5 ng/ml (normal, <5.2 ng/ml), gastrointestinal endoscopy was performed but no suspicious lesions were found in the gastrointestinal tract He was referred for a bone scan after computed tomography disclosed multiple destructive lesions in the lumbar spine. Tc-99m MDP bone scintigraphy showed multiple bone metastases.