PET/CT images of 18
F-FDG and 124
I-IAZGP in a rectal cancer patient. (A to D) Coronal maximum intensity projection PET images of 18F-FDG acquired 3 days before 124I-IAZGP administration (A) and 124I-IAZGP acquired at 3 h (B), 6 h (C), and 25 h (D) post-administration in a patient with primary rectal cancer with liver metastases. (E to G) Cross-sectional fused PET/CT images of the same patient comparing 18F-FDG (E and F left, G top) with 124I-IAZGP at 3 h (E and F right, G bottom). No evidence of 124I-IAZGP uptake is seen in either FDG-avid primary or metastatic lesions. The 124I-IAZGP MIP images (B to D) also illustrate the characteristic pattern of 124I-IAZGP clearance, initially via the urinary tract with longer term excretion via the GI tract. Note that image intensities are not directly comparable as window levels were adjusted to maximize feature visibility.