CEACAM5 and neoplasm: Within 1 h, the CEA-positive tumor showed high and specific targeting of 68Ga-IMP-288 (10.7 ± 3.6% ID/g tumor uptake) and very low uptake in normal tissues (tumor-to-blood ratio of 69.9 ± 32.3), compared to the CEA-negative tumor and inflamed muscle (lower than 1.0% ID/g).