胶质瘤治疗后假性进展的MR波谱分析

目的 探讨¹H-MRS在鉴别脑恶性胶质瘤放化疗后假性进展和肿瘤复发的价值。方法 收集已行外科手术和/或放射治疗且临床疑为复发的脑恶性胶质瘤患者26例,行单体素¹H-MRS检查。以病理检查结果或者临床随访结果作为金标准,计算MR增强扫描和波谱分析的诊断灵敏度、特异性、准确性、阳性预测值和阴性预测值。组间比较采用t检验,P < 0.05视为差异有统计学意义。结果 26例患者中共有12例诊断为肿瘤复发。复发组和假性进展组之间的Cho/Cr、Cho/NAA和NAA/Cr比值均具有统计学差异(P < 0.01)。以Cho/Cr=2.5为截断值,MRS诊断真性复发的灵敏度为100%,特异性为92.9%,准确性为96.2%。以Cho/NAA=3.42为截断值,MRS诊断真性复发的灵敏度为66.7%,特异性为92.9%。NAA/Cr比值在假性进展组高于复发组,以1.97为截断值,MRS诊断真性复发的灵敏度为92.9%,特异性为100%。结论 ¹H-MRS有助于鉴别脑恶性胶质瘤术后/放疗后假性进展和肿瘤复发。

MRS in Pseudoprogression of Glioma after Radiotherapy and Chemotherapy

Objective To analyze the value of ¹H-MRS in differentiating pseudoprogression and recurrence of malignant glioma after surgery and/or radiotherapy. Methods 26 patients with malignant glioma who had undergone surgery and/or radiotherapy and suspected to have tumor progression clinically were enrolled in this study. All patients underwent ¹H-MRS examination. The sensitivity, specificity, accuracy, PPV and NPV of contrast-enhanced MR scanning and ¹H-MRS were calculated by taking the result of pathologic examination or clinical follow-up as reference standard. The inter-group comparison was performed by using t test and a P value less than 0.05. P < 0.05 was considered statistically significant. Results 12 patients out of the total 26 patients had tumor recurrence. The difference of Cho/Cr, Cho/NAA and NAA/Cr ratio was all statistically significant. Taking 2.5 as the cut-off point for Cho/Cr, the sensitivity, specificity and accuracy were 100%, 92.9% and 96.2% respectively. Taking 3.42 as the cut-off point for Cho/NAA, the sensitivity, and specificity were 66.7% and 92.9% respectively. The group of tumor pseudoprogression had a greater NAA/Cr ratio than the group of tumor recurrence. Taking 1.97 as the cut-off point for NAA/Cr, the sensitivity and specificity were 92.9% and 100% respectively. Conclusion ¹H-MRS helps to differentiate tumor pseudoprogression and recurrence of malignant glioma after surgery and/or radiotherapy.