非典型脑膜瘤与复发性脑膜瘤的代谢谱分析：质子磁共振波谱的比较研究

脑膜瘤多为良性，但部分病例在手术后表现出复发性生长，并发生恶性转化为WHO级别2或3。尽管基因分析取得了一定进展，代谢组学分析的研究仍相对不足。在本研究中，作者利用非侵入性质子磁共振波谱（1H-MRS）比较WHO1级脑膜瘤与WHO2或3级脑膜瘤之间的代谢活性差异，旨在术前评估恶性程度，并回顾相关文献以阐明脑膜瘤研究的这一方面。在琉球大学医院，作者回顾性分析了2011年至2021年诊断为脑膜瘤的93例患者。纳入标准包括既往手术、病理诊断为脑膜瘤以及术前进行的1H-MRS。第I组包括71例WHO1级脑膜瘤，第II组包括22例，其中19例为WHO2级，3例为WHO3级。分析了患者背景及肿瘤代谢产物。结果显示，II组在肿瘤切除程度明显低于I组（p<0.01）、MIB-1标记指数（LI）显著升高（p<0.05）、既往放疗史更频繁（p<0.001），且复发率更高（p=0.005）。根据1H-MRS，除乳酸外，所有代谢物的中位肌酐（Cr）比值在II组均显著高于I组：谷氨酰胺/Cr为8.46，谷氨酸/Cr为9.49，脂质/Cr为11.36，胆碱/Cr为2.77。受试者工作特征（ROC）分析显示，10种代谢物中，谷氨酰胺的曲线下面积最大，为0.765，用于区分两组的临界值为5.76。在病理分级为WHO2或3级的脑膜瘤中，谷氨酰胺、谷氨酸、脂质和胆碱等代谢产物显著升高，且与MIB-1 LI的升高相关。II组的平均MIB-1 LI为8.58，明显高于I组，提示与病理恶性程度密切相关。因此，1H-MRS可能帮助非侵入性预测肿瘤的代谢活性和复发风险。此外，作者根据ROC分析得出，谷氨酰胺可能成为未来脑膜瘤生长的潜在指标及早期手术的益处。

Meningiomas are predominantly benign, but some cases exhibit recurrent growth after surgery and undergo malignant transformation to WHO grade 2 or grade 3. Despite progress in genetic analyses, advancements in metabolomic analysis remain less established. Herein, the authors investigated metabolic activity differences between WHO grade 1 meningiomas and WHO grade 2 or 3 meningiomas by noninvasively using proton magnetic resonance spectroscopy (1H-MRS), aiming to preoperatively estimate malignancy. They also reviewed the literature to elucidate this aspect of meningioma research.At Ryukyu University Hospital, the authors focused on 93 patients diagnosed with meningioma between 2011 and 2021. The inclusion criteria encompassed prior surgery, pathological diagnoses of meningioma, and preoperative 1H-MRS. Group I included 71 patients with WHO grade 1 meningioma and group II included 22 patients, comprising 19 and 3 with WHO grade 2 and 3 meningioma, respectively. The authors retrospectively conducted a comparative analysis of patient backgrounds and tumor metabolites.Group I and II did not differ significantly in terms of patient demographic characteristics (age and sex). Group II demonstrated a significantly lower extent of tumor resection (p < 0.01), higher MIB-1 labeling index (LI) (p < 0.05), higher incidence of prior irradiation (p < 0.001), and increased rate of tumor recurrence (p = 0.005) compared to group I. According to 1H-MRS, all metabolites, except lactate, displayed significantly higher median creatine (Cr) ratios in group II than group I: glutamine/Cr was 8.46, glutamate/Cr was 9.49, lipid/Cr was 11.36, and choline/Cr was 2.77. According to the receiver operating characteristic (ROC) analysis, glutamine had the largest area under the curve of 0.765 among 10 metabolites, and the cutoff value for distinguishing between group I and II was 5.76.In cases pathologically graded as WHO grade 2 or 3 meningiomas, metabolic products such as glutamine, glutamate, lipids, and choline increased significantly. These changes were correlated with elevation of the MIB-1 LI. In group II, the mean MIB-1 LI was 8.58, significantly higher than in group I, suggesting a strong association with pathological malignancy. Therefore, 1H-MRS may help to noninvasively predict tumor metabolic activity and tumor recurrence. Furthermore, the authors concluded from the ROC analysis that glutamine may be a potential indicator of future growth of meningioma and benefits of early surgery.