MR波谱在预测前列腺癌转移中的作用

目的 探讨MR波谱(MRS)在预测前列腺癌转移中的价值.方法 65例超声引导下穿刺活检证实的前列腺癌患者,根据临床分期分为未发生转移组(B期和C期)31例和发生骨和(或)淋巴结转移组(D期)34例,通过MRS测定2组患者癌病灶区(胆碱+肌酸)/枸橼酸盐[(Cho +Cre)/Cit]的比值,并比较其差异.同时利用描绘受试者工作特征(ROC)曲线来初步评价MRS在预测前列腺癌发生转移中的效能.结果 未发生转移组和发生转移组患者的前列腺癌区(Cho+Cre)/Cit比值分别为1.3±0.5和2.2±0.6,差异有统计学意义(t=6.38,P＜0.05).利用癌病灶区(Cho+Cre)/Cit的平均比值对肿瘤是否发生转移进行诊断试验,ROC曲线下面积(Az)值为0.87,最佳临界点为1.53,此时诊断的敏感性为94.12%(32/34),特异性为67.74%(21/31),准确性为81.54%(53/65).结论 MRS作为一种无创的MRS检查方法 ,有可能对肿瘤是否发生转移作出预测.

Prediction of metastasis of prostate cancer with three-dimensional proton MR spectroscopy:a preliminary study

Objective To determine if the three-dimensional proton magnetic resonance spectroscopic(MRS) imaging helps in diagnosing metastasis ofprostate cancer(Pca).Methods Sixty-five patients with biopsy proven Pca were recruited and divided into two groups:group 1 with metastasis(bone and/or lymph node metastasis)(n=34)and Group 2 without metastasis(n=31).Voxels were placed on cancerous area in peripheral zone and the ratios of(Cho+Cre)/Cit were measured.The mean ratio in each patient was calculated and ROC curve was drawn to determine the optimal operating point(OOP)for the prediction of Pca metastasis by the metabolite ratio.Results The mean ratio of(Cho+Cre)/Cit in cancerous area of Pca without metastasis was 1.3 ±0.5,whereas that of Pca with metastasis was 2.2±0.6.Statistically significant difference existed between the two groups(t=6.38,P＜0.05).According to the ROC analysis,the OOP was determined and interpreted at 1.53 with higher sensitivity and specificity.If Pca with metastasis was predicted as whose the mean ratio of(Cho+Cre)/Cit in cancerous area larger than 1.53,the sensitivity,specificity and accuracy for metastasis determination were 94.12%(32/34),67.74%(21/31),and 81.54%(53/65)respectively.Conclusion MRS may be a useful noninvasive method to predict the metastasis of Pca.