Indium‐111‐labeled anti‐egfr‐425 scintigraphy in the detection of malignant gliomas

Background. The monoclonal antibody anti‐epidermal growth factor receptor (EGFr)antibody‐425, against the epidermal growth factor receptor, has the potential to bind specifically to gliomas and not normal brain tissue.^1–3 A prospective study was conducted (1986–1988) to evaluate the use of Indium‐111 (¹¹¹In)‐labeled anti‐EGFr‐425 in the localization of gliomas before radioimmunotherapy with Iodine‐125 (¹²⁵I)‐labeled anti‐EGFr‐425. Methods. Twenty‐eight patients with intracranial neoplasms were injected intravenously with an average dose of 2.2 mCi ¹¹¹In‐labeled anti‐EGFr‐425. Planar and single‐photon emission computed tomography scans were performed after 48 and 72 hours. Control studies also were performed in two cases with ¹¹¹In‐labeled Co 17‐1A (a, *I antibody to colorectal cancer) and in one case with unlabeled ¹¹¹In chloride. Results. The immunoscintigraphic findings were generally in good agreement with computerized tomographic findings. The definitive diagnosis was established by biopsy findings: 23 gliomas (1 Grade I, 5 Grade II, 6 Grade III, and 11 Grade IV), 1 meningioma, and 4 metastatic lesions. The localization of gliomas with ¹¹¹In‐labeled anti‐EGF‐425 had a sensitivity of 0.96, a specificity of 0.60 and an accuracy of 0.90. Conclusion. Immunoscintigraphy with ¹¹¹‐In labeled anti‐EGFr‐425 can be useful in the management of malignant gliomas, especially before radioimmunotherapy with ¹²⁵I‐labeled anti‐EGFr‐425. Cancer 1994; 73:884–9.