ZIRCONIUM ZR-89 is used in specialized diagnostic applications using positron emission tomography (PET). An increasing interest in zirconium-89 can be attributed to the isotope's half-life, which is compatible with antibody imaging. ZR-89 as a radioimmunoconjugate, [89Zr]DFO-HuMab-5B1 was used in preclinical animal models of lung, colorectal, and pancreatic malignancies for PET imaging and was in a phase I trial for pancreatic cancer. In addition, the use of 89Zr-DFO-nimotuzumab that had low organ absorbed dose and effective dose made it suitable for potential human use for immunoPET imaging of epidermal growth factor receptor I. It is known, that epidermal growth factor receptor upregulation is associated with enhanced proliferation and drug resistance in a number of cancers.