中文摘要：

目的：探讨18F-FDG PET/CT在甲状腺病变中的应用意义.方法：回顾性分析经病理明确诊断的28例甲状腺病变的18F-FDG PET/CT影像学资料,男13例,女15例,年龄25 ～84岁,术后病理26例,穿刺病理2例,其中10例患者甲状腺有2个或多个病变,共包括8个恶性病变、31个良性病变.结果：8个恶性病变中7个甲状腺癌均表现为局灶性FDG代谢增高,1个淋巴瘤累及甲状腺病灶表现为弥漫性FDG代谢增高；31个良性病变中5个PET和CT均未显示,17个PET显示阴性、CT显示形态学改变,9个PET和CT均显示阳性改变；9个FDG代谢高摄取的良性病变包括2个结节性甲状腺肿、2个滤泡性腺瘤、2个慢性淋巴细胞性甲状腺炎、1个腺瘤样增生、1个甲状腺慢性炎症、1个亚急性甲状腺炎；甲状腺癌SUVmax与病灶最大径不相关（P=0.069）、与病灶平均密度也不相关（P=0.495）；FDG高代谢摄取的8个恶性病变和9个良性病变其SUVmax无统计学差异（P=0.134）；8个恶性病灶、31个良性病灶其钙化发生率无统计学差异（P=0.088）,但沙粒样钙化的发生率却有显著统计学差异（P=0.038）.结论：18F-FDG PET/CT单纯依靠SUV值不能鉴别甲状腺良、恶性病变,CT显示沙粒样钙化对甲状腺癌具有高度提示价值;FDG阴性摄取及FDG弥漫性摄取的甲状腺病变为良性可能性大,甲状腺局灶性FDG摄取灶为恶性病变的概率较大,前两者需建议超声随访,而后者需建议超声引导下抽吸活检.

英文摘要：

Objective： To explore the value of 18F-FDG PET/CT in the diagnosis of thyroid disease. Methods： Twentyeight patients （13 male and 15 female, aged ranged from 25 to 84 years old） with pathological diagnosis of thyroid disease were retrospectively analyzed on 18F-FDG PET/CT. Surgical operation （26 cases） and fine-needle aspiration （2 cases） were performed on these patients, of whom 10 patients had more than one lesion in thyroid gland. Therefore, 8 malignant thyroid lesions and 31 benign thyroid lesions were included in the study. Results： Focal uptake and diffuse uptake were respectively shown in 7 thyroid cancer and 1 thyroid lymphoma. Of 31 benign thyroid lesions, both PET and CT were negative in 5, both PET and CT were positive in 9, PET was negative and CT was positive in 17. Nine benign thyroid lesions with increased FDG uptake comprised nodular goiter, follicular adenoma, Hashimoto＇s thyroiditis, adenomatoid hyperplasia, chronic thyroiditis and subacute thyroiditis. The SUVmax was not correlated with maximum length and average density in thyroid cancer. There was no statistically significant difference on SUVmax between 8 malignant thyroid lesions and 9 benign thyroid lesions with high FDG uptake. The calcification did not show statistically significant difference between 8 malignant thyroid lesions and 31 benign thyroid lesions, but the sand-like calcification showed so. Conclusions： When PET/CT is used to evaluate the thyroid disease, only with SUV value can not discriminate malignant lesions from benign lesions and the sand-like calcification seen on CT may aid to identify thyroid cancer. The lesions with no FDG uptake and diffuse FDG uptake in thyroid gland are beign to a great extent, but the lesion with focal uptake in it is likely malignant. The former two are suggestive of follow-up with ultrasound, the latter is suggestive of fine-needle aspiration by ultrasound guidance.