The combination of multi-voxel MR spectroscopy with MR imaging improve the diagnostic accuracy for localization of prostate cancer.

Background: We assessed the usefulness of combined multi-voxel magnetic resonance spectroscopy (MRS) and MR imaging (MRI) in the diagnosis of prostate cancer localization.

Patients And Methods: MRS and MRI were performed in 21 patients with prostate cancer. On T2-weighted images, tumor localization was based on low signal intensity in the peripheral zone. At MRS, cancer patterns were diagnosed when the ratio of choline plus creatine to citrate was greater than 0.86. The results were analyzed with reference to pathological confirmation of prostate cancer at bilateral or unilateral lobe.

Results: Six out of 11 patients with unilateral positive biopsy specimens were diagnosed as unilateral cancer, and 9 of 10 patients with bilateral positive biopsy specimens were diagnosed as bilateral cancer on MRI. Two of 4 patients with unilateral cancer, who were not detected on MRI alone, were diagnosed as unilateral cancer on combined MRI and MRS. The accuracy of MRI alone was 71.4%, while that of combined MRI and MRS was 81.0%.

Conclusion: Combined MRI and MRS improved the diagnostic accuracy for localization of prostate cancer.