Sathekge M M, Mageza R B, Muthuphei M N, Modiba M C, Clauss R C
Department of Nuclear Medicine, Medical University of Southern Africa, Ga-Rankuwa Hospital, PO Box 545, Medunsa, 0204, South Africa.
Head Neck. 2001 Apr;23(4):305-10. doi: 10.1002/hed.1035.
Most thyroid centers use fine-needle aspiration (FNA) and technetium-99m pertechnetate for the preoperative assessment of thyroid nodules. This approach is sufficient in most cases other than follicular neoplasm, and follicular carcinoma is more common than papillary carcinoma in developing countries such as in our center. Technetium 99m-methoxyisobutylisonitrile (MIBI) proposed for myocardial perfusion was also found to be taken up by a variety of tumors including thyroid cancer.
We evaluated MIBI uptake of nodular thyroid disease and compared it with pertechnetate scan, FNA, and histologic findings for the differentiation of malignant thyroid nodules from benign lesions. Seventy-one patients were included in the study. Three-phase pertechnetate scintigraphy was completed after a single injection of 150 MBq. Perfusion/uptake mismatch (uniform perfusion with cold uptake) was regarded as positive for malignancy, whereas perfusion/uptake match (cold perfusion with cold uptake) was regarded as negative. After 1 week, 400 MBq of MIBI was injected, images were obtained at 20 minutes and 2 hours, and evaluated semiquantitatively by use of a 4-point (0-3) scoring system. MIBI scans were considered positive if there was uptake superior to normal thyroid tissue on early and delayed images (score = 3). In the following days and weeks, all patients underwent FNA followed by surgery.
Histopathologic diagnosis revealed a total of 23 thyroid carcinomas, 21 (91%) and 19 (83%) were positive on MIBI and pertechnetate, respectively. Of the 48 patients with benign nodules, 11 (23%) and 29 (60%) were positive on MIBI and pertechnetate, respectively. The specificity of MIBI, pertechnetate, and FNA is 77%, 40%, and 90%, respectively.
In combination with FNA and three-phase pertechnetate scan, MIBI could be helpful in preoperative assessment of thyroid nodules. Intense MIBI activity increases the probability of thyroid cancer, whereas reduced activity drastically decreases the probability of malignancy.
大多数甲状腺中心使用细针穿刺活检（FNA）和高锝[99mTc]酸盐进行甲状腺结节的术前评估。除滤泡性肿瘤外，这种方法在大多数情况下是足够的，并且在我们中心所在的发展中国家，滤泡癌比乳头状癌更常见。用于心肌灌注的锝[99mTc]甲氧基异丁基异腈（MIBI）也被发现可被包括甲状腺癌在内的多种肿瘤摄取。
我们评估了甲状腺结节疾病的MIBI摄取情况，并将其与高锝酸盐扫描、FNA以及组织学结果进行比较，以区分甲状腺恶性结节与良性病变。71名患者纳入本研究。单次注射150MBq后完成三相高锝酸盐闪烁扫描。灌注/摄取不匹配（均匀灌注伴冷摄取）被视为恶性阳性，而灌注/摄取匹配（冷灌注伴冷摄取）被视为阴性。1周后，注射400MBq的MIBI，在20分钟和2小时时采集图像，并使用4分（0 - 3）评分系统进行半定量评估。如果早期和延迟图像上有高于正常甲状腺组织的摄取（评分 = 3），则MIBI扫描被视为阳性。在接下来的几天和几周内，所有患者均接受FNA检查，随后进行手术。
组织病理学诊断共发现23例甲状腺癌，MIBI和高锝酸盐检查分别有21例（91%）和19例（83%）呈阳性。48例良性结节患者中，MIBI和高锝酸盐检查分别有11例（23%）和29例（60%）呈阳性。MIBI、高锝酸盐和FNA的特异性分别为77%、40%和90%。
与FNA和三相高锝酸盐扫描相结合时,MIBI有助于甲状腺结节的术前评估。MIBI活性增强增加甲状腺癌的可能性，而活性降低则大大降低恶性可能性。
