Shaw Tristan B, Jeffree Rosalind L, Thomas Paul, Goodman Steven, Debowski Maciej, Lwin Zarnie, Chua Benjamin
Department of Radiation Oncology, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia.
Griffith University, Gold Coast, Queensland, Australia.
J Med Imaging Radiat Oncol. 2019 Oct;63(5):650-656. doi: 10.1111/1754-9485.12929. Epub 2019 Aug 1.
Identifying glioma grade through imaging allows clinicians to recommend and accurately direct treatment. We sought to quantify the utility of FDG-PET/CT (18F-fluorodeoxyglucose positron emission tomography/computed tomography), alone and in combination with MRI, in identifying high-grade regions of glioma.
This is a retrospective review of patients who had an FDG-PET/CT performed as part of the workup of suspected glioma or in follow-up of known glioma. FDG-PET/CT scans were reviewed and uptake in the identifiable lesion coded as none, diffusely or focally increased. Patients also underwent gadolinium-enhanced MRI, noting regions of contrast enhancement. Sensitivity, specificity, positive and negative predictive values (PPV and NPV) were calculated for identification of high-grade histology (WHO III or IV, or metastatic disease) obtained post-FDG-PET/CT.
Thirty-three patients had 36 FDG-PET/CT and MRI scans followed by histological confirmation (biopsy or debulking). Increased FDG uptake demonstrated a sensitivity of 59% and specificity of 79%, PPV of 81% and NPV of 55% for identification of high-grade histology. MRI demonstrated a sensitivity of 77% and specificity of 86%, PPV of 89% and NPV of 71% for identification of high-grade histology. Only 64% of MRI and FDG-PET/CT scan series were concordant. When FDG-PET/CT and MRI were concordant, a specificity of 100% and PPV of 100% was achieved, however, sensitivity was 79% and NPV was 75%.
The combination of FDG-PET/CT and gadolinium-enhanced MRI demonstrated marked improvement in identifying potential high-grade disease over each modality alone. Increased FDG uptake without gadolinium enhancement rarely occurred and identified high-grade histology in a small number of patients. Due to limited sensitivity and NPV, a negative FDG-PET/CT alone, or in combination with MRI, should not guide a decision for observation where surgery would otherwise be recommended.
通过影像学检查确定胶质瘤分级可使临床医生推荐并准确指导治疗。我们试图量化氟代脱氧葡萄糖正电子发射断层显像/计算机断层扫描（FDG-PET/CT）单独及与磁共振成像（MRI）联合使用时，在识别胶质瘤高级别区域方面的效用。
这是一项对因疑似胶质瘤进行检查或已知胶质瘤进行随访而接受FDG-PET/CT检查的患者的回顾性研究。对FDG-PET/CT扫描进行评估，并将可识别病变中的摄取情况编码为无、弥漫性增加或局灶性增加。患者还接受了钆增强MRI检查，记录对比增强区域。计算FDG-PET/CT检查后识别高级别组织学（世界卫生组织III或IV级，或转移性疾病）的敏感性、特异性、阳性和阴性预测值（PPV和NPV）。
33例患者进行了36次FDG-PET/CT和MRI扫描，随后进行了组织学确认（活检或肿瘤切除）。FDG摄取增加在识别高级别组织学时的敏感性为59%，特异性为79%，PPV为81%，NPV为55%。MRI在识别高级别组织学时的敏感性为77%，特异性为86%，PPV为89%，NPV为71%。只有64%的MRI和FDG-PET/CT扫描系列结果一致。当FDG-PET/CT和MRI结果一致时，特异性为100%，PPV为100%，但敏感性为79%，NPV为75%。
与单独使用每种检查方法相比，FDG-PET/CT与钆增强MRI联合使用在识别潜在高级别疾病方面有显著改善。无钆增强的FDG摄取增加很少见，仅在少数患者中识别出高级别组织学。由于敏感性和NPV有限，单独的FDG-PET/CT阴性结果，或与MRI联合，在原本建议手术的情况下，不应作为观察决策的依据。
