Gamma camera emission tomography using radiolabelled antibodies

Single photon emission computed tomography (SPECT) of 52 patients injected with 131I and 111In labelled monoclonal antibodies has been undertaken. Patients with tumours within the thorax or lower abdomen were imaged 48-72 h following administration of 80 MBq 131I or 111In labelled monoclonal antibody. Tumour detection from the reconstructed views was compared with that from the planar images. Studies of patients injected with 131I labelled antibodies required long data collection times otherwise image quality was unsatisfactory. Emission tomography using 111In labelled antibodies provided high quality reconstructed images using data collection times acceptable for most patients, and tumour deposits not confidently detected on planar images were clearly visualised in the axial views. These studies demonstrate the potential of radiolabelled antibody emission tomography.