Purandare N C, Pramesh C S, Karimundackal G, Jiwnani S, Agrawal A, Shah S, Agarwal J P, Prabhash K, Noronha V, Joshi A, Kumar R, Rangarajan V
Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, Mumbai, Maharashtra, India.
Department of Surgical Oncology, Tata Memorial Hospital, Mumbai, Maharashtra, India.
Indian J Cancer. 2016 Apr-Jun;53(2):270-273. doi: 10.4103/0019-509X.197717.
To study the utility of fluorodeoxyglucose (FDG) positron emission tomography (PET) in predicting (1) the World Health Organization (WHO) histologic type and differentiating low-risk from high-risk types. (2) Tumor stage and differentiate early from advanced stage disease.
Patients with thymic epithelial neoplasia who underwent a pretreatment FDG-PET study were included. Tumor maximum standardized uptake value (SUVmax) was correlated with the WHO histologic type and also with the Masaoka-Koga (MK) staging system. Patients with WHO Type A, AB, and B1 were classified as low risk and those with B2 and B3 as high risk. Thymic carcinomas belonged to Type C. Patients with MK Stage I and II disease were grouped as early stage and those with Stage III and IV as an advanced stage. Differences in SUVmax between the various groups were calculated.
The SUVmax of thymic carcinomas was significantly higher as compared to low-risk (P = 0.001) and high-risk groups (P = 0.007). The SUVmax of high-risk group was also significantly higher than the low-risk group (P = 0.002). SUVmax cutoff of 6.5 was able to differentiate thymic carcinomas from thymomas with 100% sensitivity and 87.2% specificity. The SUVmax in patients with advanced stage disease showed a higher trend compared to those with early stage, but the difference was not significant (P = 0.167).
PET can differentiate thymic carcinomas from rest of the thymoma subtypes by the virtue of their higher FDG uptake. It can also provide valuable information in differentiating high-risk from low-risk thymomas and in predicting disease stage.
研究氟脱氧葡萄糖（FDG）正电子发射断层扫描（PET）在预测（1）世界卫生组织（WHO）组织学类型以及区分低风险和高风险类型方面的效用。（2）肿瘤分期以及区分疾病的早期和晚期。
纳入接受FDG - PET预处理研究的胸腺上皮肿瘤患者。肿瘤最大标准化摄取值（SUVmax）与WHO组织学类型以及Masaoka - Koga（MK）分期系统相关。WHO A型、AB型和B1型患者被分类为低风险，B2型和B3型患者为高风险。胸腺癌属于C型。MK I期和II期疾病患者归为早期，III期和IV期患者归为晚期。计算不同组之间SUVmax的差异。
与低风险组（P = 0.001）和高风险组（P = 0.007）相比，胸腺癌的SUVmax显著更高。高风险组的SUVmax也显著高于低风险组（P = 0.002）。SUVmax临界值为6.5时能够以100%的敏感性和87.2%的特异性区分胸腺癌和胸腺瘤。晚期疾病患者的SUVmax与早期患者相比呈更高趋势，但差异不显著（P = 0.167）。
PET凭借胸腺癌较高的FDG摄取量可将其与其他胸腺瘤亚型区分开来。它在区分高风险和低风险胸腺瘤以及预测疾病分期方面也能提供有价值的信息。
