MRI of the skeleton in prostate cancer staging

OBJECTIVE: To explore the value of MRI in the detection of bone metastases in newly diagnosed prostate cancer. MATERIAL AND METHODS: MRI examinations of the axial skeleton in 76 patients with newly diagnosed prostate cancer were reviewed, and the relation of these findings to the serum level of prostate specific antigen (PSA) was examined. RESULTS: MRI indicated bone metastases in 26/76 patients (34%) in the entire study group, in 4/24 (17%) with serum PSA <20 ng/ml and in 22/52 (42%) with serum PSA >20 ng/ml. CONCLUSIONS: These results suggest that MRI is a more sensitive indicator of suspected bone metastases than bone scintigraphy in the low range of serum PSA, but less sensitive in the high range. Further studies of MRI and bone scintigraphy in parallel in patients with serum PSA <20 ng/ml are needed to elucidate their relative value in the staging of patients with prostate cancer.