Parliament M B, Chapman J D, Urtasun R C, McEwan A J, Golberg L, Mercer J R, Mannan R H, Wiebe L I
Department of Radiation Oncology, Cross Cancer Institute, Edmonton, Alberta, Canada.
Br J Cancer. 1992 Jan;65(1):90-5. doi: 10.1038/bjc.1992.17.
Non-invasive predictive assays which can confirm the presence or absence of hypoxic cells in human tumours show promise for understanding the natural history of tumour oxygenation, and improving the selection of patient subsets for novel radiotherapeutic strategies. Sensitiser adducts have been proposed as markers for hypoxic cells. Misonidazole analogues radiolabelled with iodine-123 have been developed for the detection of tumour hypoxia using conventional nuclear medicine techniques. In this pilot study, we have investigated one such potential marker, 123I-iodoazomycin arabinoside (123I-IAZA). Patients with advanced malignancies have undergone planar and single-photon emission computed tomographic (SPECT) imaging after intravenous administration of 123I-IAZA. We have observed radiotracer avidity in three out of ten tumours studied to date. Normal tissue activity of variable extent was also seen in the thyroid and salivary glands, upper aerodigestive tract, liver, intestine, and urinary bladder. Quantitative analysis of those images showing radiotracer avidity revealed tumour/normal tissue (T/N) ratios of 2.3 (primary small cell lung carcinoma), 1.9 (primary malignant fibrous histiocytoma) and 3.2 (brain metastasis from small cell lung carcinoma) at 18-24 h post injection. These preliminary data suggest that the use of gamma-emitter labelled 2-nitroimidazoles as diagnostic radiopharmaceuticals is feasible and safe, and that metabolic binding of 123I-IAZA is observed in some, but not all tumours. The inference that tumour 123I-IAZA avidity could be a non-invasive measure of tumour hypoxia deserves independent confirmation with needle oximetry.
能够确认人类肿瘤中是否存在缺氧细胞的非侵入性预测检测方法，对于理解肿瘤氧合的自然史以及改善新型放射治疗策略的患者亚组选择具有重要意义。已提出敏化剂加合物作为缺氧细胞的标志物。已开发出用碘-123标记的米索硝唑类似物，用于使用传统核医学技术检测肿瘤缺氧情况。在这项初步研究中，我们研究了一种这样的潜在标志物，即123I-碘阿霉素阿拉伯糖苷（123I-IAZA）。晚期恶性肿瘤患者在静脉注射123I-IAZA后接受了平面和单光子发射计算机断层扫描（SPECT）成像。在迄今为止研究的10个肿瘤中，我们观察到有3个肿瘤对放射性示踪剂有摄取。在甲状腺、唾液腺、上消化道、肝脏、肠道和膀胱中也观察到了不同程度的正常组织活性。对那些显示有放射性示踪剂摄取的图像进行定量分析，发现在注射后18 - 24小时，肿瘤/正常组织（T/N）比值分别为2.3（原发性小细胞肺癌）、1.9（原发性恶性纤维组织细胞瘤）和3.2（小细胞肺癌脑转移）。这些初步数据表明，使用γ发射体标记的2-硝基咪唑作为诊断性放射性药物是可行且安全的，并且在一些但并非所有肿瘤中都观察到了123I-IAZA的代谢结合。关于肿瘤对123I-IAZA的摄取可能是肿瘤缺氧的一种非侵入性测量方法的推断，值得通过针式血氧测定法进行独立验证。
