Use of a Novel Arg-Gly-Asp Radioligand, ¹⁸F-AH111585, to Determine Changes in Tumor Vascularity After Antitumor Therapy

Representative coregistered small-animal PET and micro-CT images demonstrating ¹⁸F-AH111585 uptake at 120 min in Calu-6 xenograft model before (A) and after (B) administration of 3 doses of vehicle control or before (C) and after (D) 3 doses of ZD4190 (100 mg/kg). Contrast is clearly seen in Calu-6 tumors located on left shoulder region in both ZD4190-treated and vehicle control animals. The only additional higher activity concentration was found in bladder. In addition, ²²Na fiducial markers can be seen located on base of imaging bed (used for PET/CT coregistration). ROI analysis for tumor uptake before ZD4190 therapy was 1.7 %ID/g, decreasing to 1.1 %ID/g after ZD4190 therapy. Muscle uptake was maintained at 0.5 %ID/g in pre- and post-ZD4190–therapy images. For animals treated with vehicle control alone, ROI analysis for tumor uptake before vehicle control was 2.1 %ID/g, increasing to 2.5 %ID/g after therapy. Muscle uptake was maintained at 0.3 %ID/g in pre- and posttherapy images.