MRS诊断前列腺癌准确率与病理切片Gleason评分的相关性研究

A correlation study of Gleason score and the diagnostic accuracy of MRS in prostate cancer based on pathological section

目的:通过前列腺MRS和同区病理切片结果的对照研究,探讨MR波谱(MRS)诊断前列腺癌(PCa)的准确率及其与Gleason评分间的关系。方法:将5例PCa患者PCa根治术后的离体标本,以术前前列腺MRS定位像的最大横径层为标准取层。以MRS兴趣区(ROI)各体素为标准分割兴趣层标本,制成与MRS结果一一对应的病理切片。将MRS波谱变化与病理结果进行同区对照,评价(胆碱+肌酸)/枸橼酸盐((choline+creatine)/citrate,CC/C)值与Gleason评分间的关系。按Gleason评分的不同,对病理确诊的前列腺癌区进行分组。通过Spearman相关分析探讨不同Gleason评分下MRS诊断PCa的准确率。结果:共取得有效病理结果90个。以CC/C值>0.86为诊断PCa的标准,MRS诊断的有癌区65个,无癌区25个,与病理结果一致的分别为59个及14个。PCa CC/C值与Gleason评分呈正相关,具有统计学意义(r=0.746,P=0.000)。Gleason评分6分组,MRS诊断PCa的准确率为50%;Gleason评分7分组诊断准确率为53.8%;Gleason评分8分组诊断准确率为72%;Gleason评分9分和10分组诊断准确率均为100%。经Spearman相关分析,MRS诊断PCa的准确率与Gleason评分呈正相关,结果具有统计学意义(r=0.223,P=0.034)。结论:MRS诊断PCa的准确率与Gleason评分呈正相关,提示MRS诊断PCa的准确率随肿瘤恶性度的增高而上升。

Objective： To investigate the diagnostic accuracy of magnetic resonance spectroscopy （MRS） in prostate cancer （PCa） and its correlation with Gleason score by making a comparative study of prostate MRS and the corresponding pathologi cal section. Methods： Radical perineal prostatectomy was performed in 5 patients with PCa. Before operation, all the patients underwent prostate MRS scanning. According to the widest cross section in prostate 3D-MRS image, the interested layer of radical prostatectomy specimens were selected and sliced. On the basis of MRS voxels, the interested layer was cut into 15- 35 pieces equally. Each piece was numbered in agreement with the order of MRS voxels and made into pathological sections. The diagnosis of MRS was compared to pathological finding in the same area. The correlation between the ratio of （choline＋creatine）/citrate（CC/C） and Gleason score was evaluated. According to the difference of Gleason score, the PCa regions were di vided into several groups. The relationship of Gleason score and diagnostic accuracy of MRS in PCa was researched by Spear man＇s rank correlation analysis. Results： 90 regions with valid pathologic diagnosis were obtained in total. Using CC/C〉0.86 as the diagnostic standard, 65 cancer-affected regions and 25 cancer-free regions were diagnosed by MRS, among which the results consistent with pathologic diagnosis were 59 and 14, respectively. There was a significant positive correlation between the ratio of CC/C and Gleason score of PCa（r=0.746, P=0.000）. In group l（Gleason score=6）, the diagnostic accuracy of MRS in PCa was 50%. In group 2（Gleason score=7）, the diagnostic accuracy was 53.8%. In group 3（Gleason score=8）, the diagnos tic accuracy was 72%. In group 4（Gleason score=9） and group 5（Gleason score=10）, the diagnostic accuracy was 100%. Spear man＇s rank correlation analysis showed that the diagnostic accuracy of MRS in PCa was significant positively correlated to the Gleason score （r=0.223, P=0.034）. Conclusion： The correlation between the diagnostic accuracy of MRS in PCa and Gleason score was significant positive. The diagnostic accuracy of MRS in PCa may gradually increased with the malignant degree of PCa.