FUSION OF IMMUNOSCINTIGRAPHY SINGLE-PHOTON EMISSION COMPUTED-TOMOGRAPHY (SPECT) WITH CT OF THE CHEST IN PATIENTS WITH NON-SMALL-CELL LUNG-CANCER

In non-small cell lung cancer (NSCLC), accurate staging is critical in deciding between potentially curative surgery and palliative treatmen t. Image registration, or fusion, combines the unique functional infor mation provided by SPECT imaging with the excellent anatomic detail of fered by computed tomography (CT) or magnetic resonance imaging to bet ter characterize the information provided by each separate modality. I n this study, we explored the role of fusion of immunoscintigraphy SPE CT with CT in the staging of NSCLC, We fused chest CT with Tc-99m-labe led IMMU-4 anti-carcinoembryonic antigen Fab' antibody fragment SPECT in 14 patients with NSCLC using a landmark-based algorithm, The algori thm's accuracy was a measure from the center-to-center distance and th e percentage overlap of two regions of interest: one drawn on CT and w arped onto SPECT, the other drawn directly on the SPECT. We found that the average center-to-center distance was 1.3 +/- 0.8 pixels, Average overlap was 46 +/- 20%, CT-SPECT fusion helped differentiate tumor fr om normal blood pool, necrotic areas within viable tumor, tumor recurr ence from scar, and malignant lymphadenopathy from hyperplasia, We con clude that fusion of CT and SPECT augments the information provided by each separate modality, Future clinical applications of fusion in NSC LC staging using immunoscintigraphy appear promising.