College of Engineering, Peking University, Beijing, China, People's Republic of China.
J Magn Reson Imaging. 2013 Jan;37(1):194-200. doi: 10.1002/jmri.23809. Epub 2012 Sep 21.
To evaluate apparent diffusion coefficient (ADC) value, metabolic ratio ((Cho + Cr)/Cit) and the combination of the two in identifying prostate malignant regions.
Fifty-six consecutive patients with prostate biopsy results were retrospectively recruited in this study. Transrectal ultrasound-guided (TRUS) systemic prostate biopsies were used as a standard of reference. Mean ADC value and mean metabolic ratio (MMR) were calculated within each benign sextant region or malignant region. The efficiency of these two indices in prostate cancer (PCa) diagnosis is estimated in Fisher linear discriminant analysis (FLDA). The area under the receiver operating characteristic (ROC) curve was used to evaluate the distinguishing capacity of mean ADC, MMR, and the combination of the two in differentiating between noncancerous and cancerous cases.
There were significant differences for mean ADC value and MMR between malignant and benign regions. Weights of mean ADC value obtained by FLDA were much higher than those of MMR. In differentiating malignant regions, both ADC alone and combined ADC and metabolic ratio performed significantly better than MMR alone. However, accuracy improvements were not significant by using combined ADC and MMR than ADC alone.
DWI is more efficient than MR spectroscopic (MRS) in the detection of PCa in this study. Combined ADC and MMR performed significantly better than MMR alone in distinguishing malignant from benign region in prostate peripheral zone.
评估表观扩散系数（ADC）值、代谢比（（Cho + Cr）/Cit）及其组合在识别前列腺恶性区域中的作用。
本研究回顾性招募了 56 名经前列腺活检结果证实的连续患者。采用经直肠超声引导（TRUS）系统前列腺活检作为参考标准。在每个良性六分区域或恶性区域内计算平均 ADC 值和平均代谢比（MMR）。在 Fisher 线性判别分析（FLDA）中估计这两个指数在前列腺癌（PCa）诊断中的效率。接收者操作特征（ROC）曲线下面积用于评估平均 ADC、MMR 以及两者组合在区分非癌和癌病例方面的区分能力。
恶性和良性区域之间的平均 ADC 值和 MMR 存在显著差异。通过 FLDA 获得的平均 ADC 值权重远高于 MMR。在区分恶性区域时，ADC 单独和联合 ADC 和代谢比的表现均明显优于 MMR 单独。然而，使用联合 ADC 和 MMR 并不能显著提高准确性。
在这项研究中，DWI 在检测 PCa 方面比 MR 光谱（MRS）更有效。在区分前列腺外周区的恶性和良性区域时，联合 ADC 和 MMR 比 MMR 单独使用的表现明显更好。
