Magnani P, Paganelli G, Songini C, Samuel A, Sudati F, Siccardi A G, Fazio F
Institute H San Raffaele, University of Milan, Italy.
Br J Cancer. 1996 Sep;74(5):825-31. doi: 10.1038/bjc.1996.443.
To evaluate the use of pretargeted immunoscintigraphy (ISG) in the diagnosis and follow-up of patients with medullary thyroid carcinoma (MTC), we studied 25 patients with histologically proven disease; ISG was repeated after surgery in two patients. The antibody, either an anticarcinoembryonic antigen (CEA) or an antichromogranin A (CgA) biotinylated monoclonal antibody (MAb) or a cocktail of the two biotinylated MAbs was first injected. After 24 h, avidin was administrated i.v., followed by 111In-labelled biotin 24 h later. Fifty-two lesions were visualised. Six primary tumours, diagnosed by increased calcitonin levels, were all correctly diagnosed; 47 recurrences, also suspected by blood tumour markers, were detected and confirmed by cytology or histology. In one case, single photon emission tomography allowed the detection of small lymph nodes with a diameter of 4-7 mm. These lesions, not judged neoplastic by ultrasound, were confirmed to be neoplastic by fine needle aspiration. Pretargeted ISG correctly localises primary tumours and recurrences in MTC patients, when the only marker of relapse is serum elevation of calcitonin. With this three-step pretargeting method, cocktails of potentially useful MAbs can be used, avoiding false-negative studies that may occur when CEA or CgA are not expressed.
为评估预靶向免疫闪烁显像（ISG）在甲状腺髓样癌（MTC）患者诊断及随访中的应用，我们研究了25例经组织学证实患有该病的患者；两名患者术后重复进行了ISG检查。首先注射抗体，该抗体为抗癌胚抗原（CEA）或抗嗜铬粒蛋白A（CgA）生物素化单克隆抗体（MAb）或两种生物素化MAb的混合物。24小时后静脉注射抗生物素蛋白，随后在24小时后注射111In标记的生物素。共发现52个病灶。通过降钙素水平升高诊断出的6例原发性肿瘤均被正确诊断；47例复发灶，也通过血液肿瘤标志物怀疑，并经细胞学或组织学证实。在1例病例中，单光子发射断层扫描检测到直径为4 - 7毫米的小淋巴结。这些病灶经超声判断不是肿瘤性的，但经细针穿刺证实为肿瘤性。当复发的唯一标志物是血清降钙素升高时，预靶向ISG能正确定位MTC患者的原发性肿瘤和复发灶。采用这种三步预靶向方法，可以使用潜在有用的MAb混合物，避免在CEA或CgA不表达时可能出现的假阴性研究。
