MAGNETIC-RESONANCE-IMAGING FOR DETECTION OF PROSTATE-CANCER METASTATIC TO BONE

The diagnosis of prostate cancer metastatic to bone currently is made with plain x-rays, radio-nuclide bone scans, and acid and alkaline pho sphatases. We used magnetic resonance imaging (MRI) in 18 patients wit h known prostate cancer to resolve conflicting evidence of metastases found on bone scans, plain films and serum enzyme determinations. Of 8 bone scans interpreted as positive MRI was read as negative for metas tatic disease in 2. Of 5 negative bone scans 1 MRI study was interpret ed as positive. All 5 equivocal bone scans demonstrated no osseous les ions on MRI. In addition, in 6 patients with evidence of bone metastas es the serial MRI scans following hormonal therapy demonstrated radiog raphic and clinical improvement. We conclude that MRI is helpful in th e diagnosis of metastatic prostate cancer when other radiographic exam inations are enigmatic and that MRI can be used to determine the respo nse to hormonal treatment.