From the *Nuclear Medicine & Physics Unit, Fondazione Salvatore Maugeri, Pavia, Italy; †Service of Nuclear Medicine, Policlinico Sant'Orsola-Malpighi, University of Bologna, Bologna, Italy; ‡Oncology Unit, Fondazione Salvatore Maugeri, Pavia, Italy; §Department of Urology, Policlinico Sant' Orsola-Malpighi, University of Bologna, Italy; ¶Department of Nuclear Medicine & PET/CT Centre, Santa Maria della Misericordia Hospital Rovigo, Italy; and ∥Radiology Department, University of Southern California, Los Angeles, CA.
Clin Nucl Med. 2014 Jun;39(6):e320-4. doi: 10.1097/RLU.0000000000000382.
The aim of our retrospective study was to assess the usefulness of F-FDG PET/CT in the restaging of clear cell renal cell carcinoma (RCC) patients.
Sixty-nine patients (median age = 62 years; range = 36-86 years) affected by clear cell RCC (TNM at staging: T1, 42 patients; T2, 13 patients; T3, 11 patients; T4, 3 patients; Fuhrman grade: G2, 47 patients; G3, 20 patients; G4, 2 patients) underwent whole-body F-FDG PET/CT to restage the disease after nephrectomy for clinical or radiological suspicion of metastases. Areas of abnormal uptake at PET/CT were classified, taking the liver uptake as reference, as follows: 1 = faint uptake, lower than liver; 2 = moderate uptake, equal to liver; and 3 = high uptake, higher than liver. Validation of F-FDG PET/CT results was established by (1) biopsy (23 patients) and (2) other imaging modalities (addressed BS; c.e.CT; MRI; F-fluoride PET/CT; subsequent F-FDG PET/CT), and/or clinical and radiological follow-up of 12 months (46 patients).
F-FDG PET/CT was positive in 42 patients and negative in 27 patients. Sixteen patients presented single lesions and 26 patients presented multiple localizations of the disease. On a patient basis, 40 patients resulted true positive, 2 patient false positive, 23 patients true negative, and 4 patients false negative. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 90%, 92%, 91%, 95%, and 85%, respectively. On a lesion basis, PET/CT detected 114 areas of abnormal uptake in 42 positive patients of which 112 resulted to be true positive. FDG uptake of the true positive lesions resulted to be high in 83 cases, moderate in 17 lesions, and finally faint in 12 lesions.
F-FDG PET/CT demonstrated a good sensitivity in the restaging of clear cell RCC. Most of the lesions showed intense activity. According to our results, it seems that the use of F-FDG PET/CT in the restaging of RCC is feasible because the number of false-negative cases is limited.
本回顾性研究的目的是评估 F-FDG PET/CT 在透明细胞肾细胞癌（RCC）患者分期中的作用。
69 例透明细胞 RCC 患者（中位年龄=62 岁；范围=36-86 岁）接受全身 F-FDG PET/CT 检查，以在肾切除术后对疾病进行分期，这些患者有临床或影像学怀疑转移。根据 PET/CT 上摄取的情况，将摄取异常的部位与肝脏摄取进行比较，分为以下几类：1=摄取微弱，低于肝脏；2=摄取中等，与肝脏相等；3=摄取较高，高于肝脏。通过（1）活检（23 例）和（2）其他影像学方法（BS；c.e.CT；MRI；F-氟化物 PET/CT；随后的 F-FDG PET/CT），以及/或对 46 例患者进行 12 个月的临床和影像学随访来验证 F-FDG PET/CT 结果。
42 例患者 F-FDG PET/CT 阳性，27 例患者 F-FDG PET/CT 阴性。16 例患者有单个病灶，26 例患者有多个病灶。在患者层面上，40 例患者为真阳性，2 例患者为假阳性，23 例患者为真阴性，4 例患者为假阴性。灵敏度、特异性、准确性、阳性预测值和阴性预测值分别为 90%、92%、91%、95%和 85%。在病灶层面上，42 例阳性患者中 PET/CT 共检测到 114 个异常摄取部位，其中 112 个为真阳性。真阳性病灶的 FDG 摄取结果为 83 例为高摄取，17 例为中摄取，12 例为低摄取。
F-FDG PET/CT 在透明细胞 RCC 的分期中具有良好的灵敏度。大多数病灶显示出强烈的活性。根据我们的结果，在 RCC 的分期中使用 F-FDG PET/CT 似乎是可行的，因为假阴性病例的数量有限。
