Volpe C M, Abdel-Nabi H H, Kulaylat M N, Doerr R J
Department of Surgery, State University of New York at Buffalo and Veterans Administration Medical Center, USA.
Ann Surg Oncol. 1998 Sep;5(6):489-94. doi: 10.1007/BF02303640.
External immunoscintigraphy using a single monoclonal antibody has been employed successfully to localize primary, recurrent, and occult colorectal carcinoma. This prospective study investigated the accuracy and sensitivity of external immunoscintigraphy when the combination or "cocktail" of radiolabeled monoclonal antibodies, CYT-103 (an IgG1a) and CYT-372 (an IgG2b) directed against TAG-72 and CEA, respectively, is given to patients with known or suspected colorectal cancer.
Eleven patients enrolled in this open label phase I/II study underwent preoperative external immunoscintigraphy after intravenous cocktail administration of two indium 111-labeled monoclonal antibodies (MoAb), CYT103 and CYT372. Antibody dose ranged from 0.2 mg (five patients) to 1.0 mg (six patients), each antibody radiolabeled with 2.5 mCi of indium 111, delivering a total dose of 5 mCi per patient. Planar and SPECT images were performed 2 to 5 days postinjection. Suspected lesions were surgically resected within 2 weeks of injection.
A total of 23 lesions (sites) were identified in the eleven patients, 19 of which were confirmed by pathology (hematoxylin and eosin [H&E]). Cocktail immunoscintigrams identified 16 of the 19 confirmed lesions. Computed tomography (CT) scan detected 9 of the 19 lesions. The sensitivities of cocktail immunoscintigraphy and CT scan for the detection of colorectal cancer were 84% and 64%, respectively. The positive predictive value for immunoscintigraphy was 94%. The antibody scans detected six occult, previously unsuspected lesions. Cocktail immunoscintigraphy changed the surgical management in four of the 11 (36%) patients.
The combination of In 111 CYT-103 and CYT-372 improved the sensitivity of external immunoscintigraphy for the detection of colorectal cancer compared to that obtained with a single MoAb imaging. Cocktail antibody imaging may enhance the staging and management of patients with cancers of colon and rectum.
使用单一单克隆抗体的体外免疫闪烁显像已成功用于定位原发性、复发性和隐匿性结直肠癌。这项前瞻性研究调查了将分别针对TAG-72和癌胚抗原（CEA）的放射性标记单克隆抗体CYT-103（一种IgG1a）和CYT-372（一种IgG2b）联合使用或“混合”给予已知或疑似结直肠癌患者时，体外免疫闪烁显像的准确性和敏感性。
参与这项开放标签I/II期研究的11名患者在静脉注射两种铟111标记的单克隆抗体（MoAb）CYT103和CYT372的混合制剂后接受术前体外免疫闪烁显像。抗体剂量范围为0.2毫克（5名患者）至1.0毫克（6名患者），每种抗体用2.5毫居里铟111进行放射性标记，每位患者的总剂量为5毫居里。在注射后2至5天进行平面和单光子发射计算机断层扫描（SPECT）图像检查。在注射后2周内对疑似病变进行手术切除。
11名患者共发现23个病变（部位），其中19个经病理检查（苏木精和伊红[H&E]染色）确诊。混合免疫闪烁显像识别出了19个确诊病变中的16个。计算机断层扫描（CT）检测到19个病变中的9个。混合免疫闪烁显像和CT扫描检测结直肠癌的敏感性分别为84%和64%。免疫闪烁显像的阳性预测值为94%。抗体扫描检测到6个隐匿性、先前未被怀疑的病变。混合免疫闪烁显像改变了11名患者中4名（36%）患者的手术治疗方案。
与使用单一MoAb成像相比，铟111标记的CYT-103和CYT-372联合使用提高了体外免疫闪烁显像检测结直肠癌的敏感性。混合抗体成像可能会改善结肠癌和直肠癌患者的分期及治疗管理。
