Biochemical and Pathophysiological Premises to Positron Emission Tomography With Choline Radiotracers.

Choline is a quaternary ammonium base that represents an essential component of phospholipids and cell membranes. Malignant transformation is associated with an abnormal choline metabolism at a higher levels with respect to those exclusively due to cell multiplication. The use of Positron Emission Tomography/Computed Tomography (PET/CT) with radiocholine (RCH), labeled with 11 C or 18 F, is widely diffuse in oncology, with main reference to restaging of patients with prostate cancer. The enhanced concentration in neoplasm is based not only on the increasing growing rate, but also on more specific issues, such as the augmented uptake in malignant cells due to the up-regulation of choline kinase. Furthermore the role of hypoxia in decreasing choline's uptake determine an in vivo concentration only in well oxygenated tumors, with a lower uptake when malignancy increases, that is, in tumors positive at 18 F-Fluoro-deoxyglucose. In this paper we have analyzed the most important issues related to the possible utilization of RCH in diagnostic imaging of human cancer. J. Cell. Physiol. 232: 270-275, 2017.