ADVANCED TECHNIQUES OF MAGNETIC RESONANCE IMAGING FOR PROSTATE CANCER

Abstract

One of the most common malignancies in elderly men is prostate cancer. Early detection together with proper localization and staging has a high effect on the prognosis of the disease and outcome of treatment. Recently advanced MRI techniques have been applied including, diffusion weighted imaging (DWI) MRI, dynamic contrast enhanced (DCE) MRI, MR spectroscopy (MRS) and MR elastography (MRE). MRI has a good sensitivity; however the specificity for prostate malignancy is low. This is because; few other conditions also lead to T2 hypointense lesions in the peripheral zone. They are - post-biopsy hemorrhage, post-radiation or hormone therapy, post-inflammatory changes and dystrophic changes. It is also difficult to detect the lesions arising from the central or transition zone on SE T2 weighted images since they also show low to intermediate signal intensity on T2W images. Also, the heterogeneity of the central and transition zone increases as the age advances due to benign prostatic hyperplasia (BPH). Prostatic malignancy being as disease of the old, this forms a confounding factor. Due to these issues, we use various functional MRI techniques to compliment the conventional MRI and improve diagnostic accuracy since no single sequence is sufficient to completely characterize prostate malignancy.