Development of tumor-imaging and -therapy on small cell lung cancer by chimera antibody.

小细胞肺癌（SCLC）占所有肺癌的20%。准确的分期对于做出治疗决定至关重要。目前临床分期包括胸部X线及CT、头部及腹部CT、骨扫描及骨髓检查。100多名新诊断的SCLC患者在给予15-30 mCi Tc-199m标记TFS-2 Fab后14-17小时进行了成像。中期分析显示，单独TFS-2成像可检测约80%的SCLC受累器官，识别85%的广泛病变患者，阳性预测值为95%。没有其他诊断测试达到这样的灵敏度和准确性。单独TFS-2成像实际上与分期SCLC的整个标准测试一样好。TFS-2成像也抢了从有限疾病到广泛疾病的先机，15%的患者被标准方法诊断为有限疾病。300muCi ^<131> i -标记TFS-2可抑制裸鼠SCLC异种移植物的生长。治疗效果呈剂量依赖性，用500muCi ^<131>I- tfs -2治疗的动物肿瘤完全消失。2.7例肺癌患者静脉注射^<131>I- tfs -2。所有患者均行肿瘤显像，未见肿瘤消退。铼186 （β -发射器）标记的TFS-2在SCLC治疗中也失败。这种失败似乎可以通过增加辐射剂量来克服，使用另一种针对相同抗原的单克隆抗体作为治疗性放射性核素的载体。针对同一抗原的新的单克隆抗体的开发正在进行中。

Small cell lung cancer (SCLC) represents 20% of all lung cancers. Accurate staging is critical for making therapeutic decisions. Clinical staging currently involves chest X ray and CT, CT head and abdomen, bone scan, and bone marrow examinations. More than 100 patients with newly diagnosed SCLC have been imaged 14-17 hours after administration of 15-30 mCi Tc-199m labaled TFS-2 Fab. Interium analysis shows that TFS-2 imaging alone detects about 80% of all organs involved with SCLC and identifies 85% of patients with extensive disease with a positive predicted value of 95%. No other diagnostic test approached this sensitivity and accuracy. TFS-2 imaging alone is virtually as good as the entire standard battery of tests in staging SCLC. TFS-2 imaging also upstaged from limited to extensive disease 15% of patients staged as limited by standard methods.Administration of 300muCi ^<131>I-labeled TFS-2 inhibited the growth of SCLC xenografts in nude mice. The therapeutic effect was dose-dependent and complete disappearcnce of the tumor was observed in animals treated with 500muCi of ^<131>I TFS-2.7 patients with lung cancers were given intravenously with ^<131>I-TFS-2. Although tumor imaging was obtained in all the patients, tumor regression was not observed. Rhenium 186 (beta-emitter) labeled TFS-2 also failed in SCLC therapy. This failure appears to be overcome by increasing the radiation dose, using another monoclonal antibodies to the same antigen as carriers of the therapeutic radionuclide.Development of the new monoclonal antibodies to the same antigen is ongoing.