分析腫瘤核心與腫瘤旁水腫之核磁掃描頻譜影像區分惡性腦瘤與腦轉移

Differentiation of High Grade Gliomas from Metastasis Using Magnetic Resonance Spectroscopy in Tumoral Core and Peritumoral Edema

陳靜玟(Ching-Wen Chen) ； 吳綠茵(Liuh-In-Wu) ； 陳淑珍(Shu-Chen Chen) ； 林美吟(Mei-Yin Lin) ； 蔡宏名(Hong-Ming Tsai) ； 莊明宗(Ming-Tsung Chuang)

《臺灣醫事放射期刊》 2卷1期 (2014/01) Pp. 47-52

https://doi.org/10.6717/JTMRT.201401_2(1).0008

摘要

傳統的核磁共振影像用來區分原發性腦癌與腦轉移有其困難，主要是因為這兩者影像可以很類似。在腦部腫瘤旁會有所謂的腫瘤旁水腫，這部分與腦瘤中心部位(又稱為腫瘤核心)的成分有所不同，之前研究認為如果是原發性癌的話，它的腫瘤旁水腫可能會有浸潤性腫瘤細胞；如果是腦轉移瘤，它的腫瘤旁水腫比較不會有浸潤性腫瘤細胞 。不過有關這部份的鑑別診斷在傳統的MRI 影像實難區分。 本研究利用核磁掃描頻譜影像(MR spectroscopy, MRS)圈選不同ROI (region of interest)來比較腫瘤核心與腫瘤旁水腫其代謝物的差異，希望能藉由分析腫瘤核心與腫瘤旁水腫之核磁掃描頻譜影像來區分惡性腦瘤與腦轉移。本研究採取回溯型研究方式，分析從2011 年1 月1 日到2012 年12 月31 日於本院執行腦瘤開刀患者(共313 人)之MRI 與MRS 影像，分析其腫瘤核心與腫瘤旁水腫之核磁掃描頻譜影像，並回顧病歷與病理結果(惡性腦瘤或腦轉移)。並繪製接收操作特徵曲線(ROC 曲線,Receiver operating characteristic (ROC) curve)以找出最佳閥值(cutoff value)來計算敏感性，特異性，陽性預測值，陰性預測值與正確率作為最佳閥值的決定標準。結果發現如果以腫瘤旁水腫Cho/Cr 為1.39 為最佳閥值時，所得到的敏感性為100%，特異性為72.73%，陽性預測值為75%，陰性預測值為100%，與正確率為85%。 如果以腫瘤核心Cho/Cr 為2.495 為最佳閥值時，所得到的敏感性為66.67%，特異性為81.82%，陽性預測值為75%，陰性預測值為75%，與正確率為75%。因此本研究之結論為惡性腫瘤的腫瘤旁水腫 Cho/Cr 值會比轉移瘤高，利用此特性可以增加診斷率。

關鍵字

核磁掃描頻譜影像 ； 腦轉移 ； 腦癌 ； 腫瘤旁水腫

並列摘要

Conventional magnetic resonance imaging(MRI) is problematic to differentiate between brain metastasis and primary glioma because their appearances look similar on MR images. Previous studies have demonstrated that primary and metastasis brain tumor are pathologically different disease entities and have different manifestation of infiltration .The disparate patterns infiltration have been widely recognized ; patients with primary glioma present a combination of vasogenic edema and neoplastic cell infiltration and patients with metastasis brain tumor manifest vasogenic infiltration. The magnetic resonance spectroscopy (MRS) can be used to analyze metabolism of the region of interest, such as choline/creatine (Cho/Cr). The purpose of the study is to differentiate primary glioma and brain metastasis using MRS on peritumoral edema and tumoral core, respectively. We retrospectively analyzed medical charts, pathological results and MRS images of patients who underwent brain tumor surgery during Jan. 01 2011 to Dec. 31 2012. Cutoff values of Cho/Cr ratio in the peritumoral edema, as well as Cho/Cr ratio in the tumoral core for distinguishing high-grade glioma from metastases were determined by receiver operating characteristic (ROC) curve analysis. ROC analysis demonstrated a cutoff value of 1.39 for peritumoral Cho/Cr ratio to provide sensitivity, specificity, positive (PPV), negative predictive values (NPV) and accuracy of 100%, 72.73%, 75%, 100% and 85%, respectively, for discrimination between high-grade gliomas and metastases. By using a cutoff value of 2.495 for tumoral core Cho/Cr ratio, the sensitivity was 66.67%, the specificity was 81.82%, the PPV was 75%, the NPV was 75% and the accuracy was 75%. The results of the study demonstrate that MRS can differentiate high-grade gliomas from metastases,especially with pertitumoral measurements.

並列關鍵字

magnetic resonance spectroscopy ； metastases ； brain glioma ； peritumoral edema