Diffusion MRI applications i̇n the diagnosis of prostate cancer

Over past 20 years, incidence of prostate cancer was increased and prostate cancer is the one of most common cancers seen in men.Rectal examination (digital), transrectal ultrasonography (TRUS) and blood prostate specific antigen (PSA) are the methods used for diagnosis and screening.Diffusion-weighted imaging (DWI) shows molecular diffusion in biological tissues. In the medical field, DWI first came into use in the field of neuroradiology, then after begun using in other organ pathologies such as bone, breast, kidney and liver. Also there are studies about usage of DWI fordetecting malignancy.This study was aimed to determine the application of diffusion MRI for diagnosis prostate cancer and to determine cut-off values of Apparent diffusion coefficients (ADCs) for diagnosis of prostate cancer. This study was planned retrospectively. Research is conducted with 50 male patients who admitted to Duzce University School of Medicine Department of Radiology for biopsy and MRI of prostate lesions. To determine the cut-off value of ADC values in detecting prostate malignancy ROC (Receiver Operating Characteristic) curve is used. Our study suggests that the mean ADC values for patients diagnosed with malignant tissues for b 800 and b 500 both values were significantly lower in patients diagnosed with benign tissue.The best cut-off ADC value of b 500 to be used for predicting malignancy were identified as 1178.50 x10-6. For this value, sensitivity was found 96.3%, specificity was 100%, positive predictive value was 100% and negative predictive value was 95.8%.The best cut-off ADC value of b 800 to be used for predicting malignancy were identified as 1197.50 x10-6. For this value, sensitivity was found 100%, specificity was 95.7%, positive predictive value was 96.4% and negative predictive value was 100%. Key words: prostate cancer, diffusion weighted imaging, DWI, ADC, ROC curve, cut-off