Evaluation of recurrent epidermoid tumors of head and neck by immuno-SPECT with monoclonal IOR EGF/R3 antibody marked with Tc-99m

Monoclonal antibody ior egf/r3 is an IgG2a that recognizes the epidermal growth factor receptor. The aim of this study was to evaluate the clinical value of Tc-99m ior egf/r3 for the detection of local and regional recurrences from squamous cell carcinomas of the head and neck (SCCHN). We studied 18 male patients, with a previously resected SCCHN: tongue (n=7), tonsil (n=6) and larynx carcinoma (n=5). All patients were suspected of having local recurrences (n=9) or cervical lymph node metastases (n=9) when enrolling in the study. Patients were administered 3mg/1.11 GBq of the Tc-99m-labelled antibody by intravenous injection. Planar images of the head and neck were acquired immediately and at 6-8 hrs. after injection. A SPECT was performed after that, using a 360 orbit with 64 images. Scintigraphic data was correlated with histopathology in all cases. Immediate planar images showed lesion uptake in 4/13 patients with confirmed recurrences (30.8%), whereas delayed images demonstrated abnormal uptake in 7/13 (53.8%) metastases. However, immuno-SPECT detected metastatic disease in 5/6 patients with lymph node metastases and in 5/7 with local recurrences (10/13, 76.9%). No false-positive case was observed. These preliminary findings suggest the potential of Tc-99m ior egf/r3 in the evaluation of recurrent SCCHN (Au)