关键词: 中央腺体前列腺癌, 基质型增生, 腺体型增生, 弥散加权成像, 表观扩散系数

Abstract: Background and purpose: Differentiating central gland prostate cancer (CGPCa) from benign prostatic hyperplasia (BPH) has always been one of the difficult clinical problems. Traditional examination methods can not be used to distinguish them well. Monoexponential and biexponential diffusion weighted imaging (DWI) models can quantitatively reflect the information of tissue diffusion and blood perfusion. This study aimed to investigate the value of parameters derived from monoexponential and biexponential DWI models (parameter derived from monoexponential DWI: ADC _total ; parameters derived from biexponential DWI: ADC slow , ADC fast and f) for distinguishing CGPCa from BPH. Methods: We retrospectively analyzed the megnatic resonance imaging (MRI) and clinical data of 36 patients with CGPCa and 48 patients with BPH ［25 patients with stromal hyperplasia (SH) and 23 patients with glandular hyperplasia (GH)］proved by prostate biopsy at Changhai Hospital, Naval Medical University, Second Military Medical University. MRI examinations included multiple-b-value (0, 50, 100, 150, 200, 500, 800, 1 000, 1 500, 2 000 s/mm ² ) DWI. Drawing the region of interest (ROI), we could measure the values of ADC _total , ADC _slow , ADC _fast and f value for the three pathological types. ANOVA and LSD-t test were used to compare the differences of the parameters. By using the receiver operating characteristic (ROC) curves, the diagnostic performances of these parameters were calculated in differentiating CGPCa from BPH. Results: Among the three groups, there were significant differences in both ADC _total and ADC _slow (P<0.000 1), while there was no difference in ADC _fast (P=0.685). There was significant difference in f value between CGPCa and SH (P=0.002) only. In differentiating CGPCa from BPH, the areas under the ROC curves for ADC _total and ADC _slow were the same (0.998), and the diagnostic performances of ADC _total and ADC _slow were high. The areas under the ROC curve for f value was 0.674. There were significant differences in the areas under the ROC curves between ADC _total , ADC _slow and f value (P<0.000 1). Conclusion: Parameters derived from monoexponential DWI (ADC _total ) and biexponential DWI (ADC _slow ) both can reflect the diffusion of water molecules near the cell structure in tissues, which are of great value in distinguishing CGPCa from BPH.

Key words: Central gland prostate cancer, Stromal hyperplasia, Glandular hyperplasia, Diffusion weighted imaging, ADC