Charest Mathieu, Singnurkar Amit, Hickeson Marc, Novales J A, Derbekyan Vilma
Service of Nuclear Medicine, Lakeshore General Hospital, Montreal, Canada.
Clin Nucl Med. 2008 Jul;33(7):455-8. doi: 10.1097/RLU.0b013e31817793bb.
A growing number of studies have demonstrated the usefulness of FDG PET-CT in the preoperative assessment of soft tissue sarcomas. We report a case of a patient with a known low-grade liposarcoma demonstrating only mild hypermetabolism on a FDG PET-CT study. An incidental osseous lesion was found in the distal tibia of the same extremity during the initial workup. This tibial lesion was significantly more intense on the FDG PET-CT study than the primary sarcoma. Further investigation showed this to be an unexpected benign fibrous dysplasia. We present this case as an example of the discrepancy of FDG activity, which may exist between truly malignant and benign lesions that may arise from soft tissue and osseous structures. A benign process should remain in the differential diagnosis for hypermetabolic lesions when evaluating a case of known malignancy, especially when the degree of uptake of that lesion differs significantly from that of the primary lesion.
越来越多的研究表明，氟代脱氧葡萄糖正电子发射断层扫描-计算机断层扫描（FDG PET-CT）在软组织肉瘤的术前评估中具有实用性。我们报告一例已知低度脂肪肉瘤患者，其在FDG PET-CT检查中仅显示轻度代谢增高。在初始检查期间，于同一肢体的胫骨干骺端发现了一个偶然的骨病变。该胫骨病变在FDG PET-CT检查中比原发性肉瘤的代谢明显更活跃。进一步检查显示这是一个意外的良性骨纤维结构不良。我们将此病例作为FDG活性差异的一个例子呈现，这种差异可能存在于源于软组织和骨结构的真正恶性病变与良性病变之间。在评估已知恶性肿瘤病例时，对于代谢增高的病变，尤其是当该病变的摄取程度与原发性病变有显著差异时，良性病变应始终保留在鉴别诊断中。
