Kincaid P K, El-Saden S M, Park S H, Goy B W
Department of Radiological Sciences, UCLA Center for the Health Sciences, Los Angeles, CA 90095, USA.
AJNR Am J Neuroradiol. 1998 May;19(5):801-6.
To date there have been only scattered case reports comparing the nuclear medicine characteristics of gangliogliomas with their histologic grade. We sought to determine the relative usefulness of nuclear medicine scanning, CT, and MR imaging in predicting the histologic grade of these tumors.
Eleven cases of pathologically proved ganglioglioma were analyzed retrospectively. Preoperative positron emission tomography with 18-fluorodeoxyglucose (FDG-PET), thallium chloride Tl 201 single-photon emission computed tomography (201Tl-SPECT), CT, and MR imaging studies were reviewed and compared with histologic tumor grade. FDG-PET scans were inspected visually for tumor metabolic activity relative to activity of normal gray and white matter. 201Tl-SPECT scans were analyzed for tumor activity using regions of interest and activity ratios. CT and MR studies were reviewed for the presence of conventional radiologic features of malignancy (ie, enhancement and edema).
Eleven patients had a total of 15 nuclear scans. Eight of nine gangliogliomas scanned with FDG-PET showed tumor hypometabolism, the ninth was normal. All nine were low-grade gangliogliomas. Increased 201Tl-SPECT activity was seen in two high-grade gangliogliomas. The third 201Tl-SPECT scan, of a low-grade ganglioglioma, was normal. CT and MR studies showed enhancement in four gangliogliomas, of which two were high grade and two low grade. Edema was seen only in conjunction with the two high-grade gangliogliomas.
FDG-PET and 201Tl-SPECT are 100% correlative in preoperative prediction of histologic grade of ganglioglioma. Tumors with decreased or normal PET or SPECT activity were low grade; tumors with increased SPECT activity were high grade. These results may be more reliable than CT and MR imaging findings in assessing tumor grade, and they may be of value for surgical planning and determining patient prognosis.
迄今为止，仅有零散的病例报告比较了神经节胶质瘤的核医学特征与其组织学分级。我们试图确定核医学扫描、CT和磁共振成像在预测这些肿瘤组织学分级方面的相对效用。
对11例经病理证实的神经节胶质瘤病例进行回顾性分析。回顾术前18氟脱氧葡萄糖正电子发射断层扫描（FDG-PET）、氯化铊Tl 201单光子发射计算机断层扫描（201Tl-SPECT）、CT和磁共振成像研究，并与肿瘤组织学分级进行比较。FDG-PET扫描通过肉眼检查肿瘤代谢活性与正常灰质和白质活性的关系。使用感兴趣区域和活性比分析201Tl-SPECT扫描的肿瘤活性。对CT和磁共振研究进行回顾，以确定是否存在恶性肿瘤的传统放射学特征（即强化和水肿）。
11例患者共进行了15次核扫描。9例接受FDG-PET扫描的神经节胶质瘤中有8例显示肿瘤代谢减低，第9例正常。所有9例均为低级别神经节胶质瘤。2例高级别神经节胶质瘤的201Tl-SPECT活性增加。第3例低级别神经节胶质瘤的201Tl-SPECT扫描正常。CT和磁共振研究显示4例神经节胶质瘤有强化，其中2例为高级别，2例为低级别。仅在2例高级别神经节胶质瘤中观察到水肿。
FDG-PET和201Tl-SPECT在术前预测神经节胶质瘤组织学分级方面相关性为100%。PET或SPECT活性降低或正常的肿瘤为低级别；SPECT活性增加的肿瘤为高级别。在评估肿瘤分级方面，这些结果可能比CT和磁共振成像结果更可靠，并且它们可能对手术规划和确定患者预后有价值。
