磁共振波谱对前列腺癌的诊断价值

Value of magnetic resonance spectroscopy in diagnose of prostate cancer

目的探讨三维磁共振波谱(magnetic resonance spectroscopy,MRS)成像在前列腺癌诊断中的应用价值。方法对19例经病理证实的前列腺癌、7例前列腺增生患者进行常规磁共振成像(magnetic resonance imaging,MRI)及增强扫描、MRS检查。增强扫描进行SI-T曲线描记,并将其结果分为三型,将Ⅰ型及Ⅱ型作为慢性前列腺增生的诊断标准,Ⅲ型为前列腺癌的诊断标准。MRS成像计算(cho+cre)/Cit的比值,比值大于0.99为前列腺癌的可疑波谱,将病灶的多体素取平均值,并与病理及其他磁共振方法相对照,比较三者的诊断效能。结果前列腺癌的(cho+cre)/cit比值为2.26±0.52,良性前列腺增生的比值为0.60±0.37,前列腺癌的(Cho+Cre)/Cit值明显高于前列腺增生(P<0.01),与病理结果相对照,MRS对前列腺癌的定性诊断优于磁共振平扫(P<0.05),同样优于增强扫描(P<0.05)。结论MRS对于前列腺癌与非癌组织的鉴别诊断有较高的准确性和特异性,对前列腺癌的诊断有较高的应用价值。

Objective To evaluate the value of magnetic resonance spectroscopy（MRS） in the diagnose of prostate cancer（PCa）.Methods Nineteen cases of prostate cancer proved by pathology and seven cases of benign prostate hyperplasia（BPH） were examined by plain,contrast-enhanced MRI and MRS.The results of contrast-enhanced MRI were evaluated by time-signal intensity curves（SI-T curves） and the curves were classified according to PCa or BPH as type Ⅰ、type Ⅱ and type Ⅲ.The SI-T curves of BPH were mainly type Ⅰ and type Ⅱ.Type Ⅲ most appeared in PCa.MRS corresponding（Choline＋ Creatine）/Citrate radios were calculated on the basis of the MRS metabolic maps.The case may be PCa if the ratios﹥0.99.The average ratio of multi-voxel was calculated for lesions.All methods were contrasted and evaluated the positive rate of the diagnosis.Results The average ratio of（Cho＋Cre）/Cit for PCa（2.26±0.52）was statistically higher than BPH（0.60±0.37）（P〈0.01）.Compared with pathology,diagnosis of the cases of PCa by using MRS were better than the cases by using MRI（P〈0.05）,so and the results of contrast-enhanced MRI（P〈0.05）.Conclusion MRS has high accuracy and specificity for the differential diagnosis of PCa and BPH,and be of high application value for the diagosis of PCa.