Research Article Uptake of 18 F-FET and 18 F-FCH in Human Glioblastoma T98G Cell Line after Irradiation with Photons or Carbon Ions Francesca Pasi, 1,2 Marco Giovanni Persico, 3,4 Federica Eleonora Buroni, 3 Carlo Aprile, 3,5 Marina Hodolic, 6 Franco Corbella, 1 Rosanna Nano, 2 Angelica Facoetti, 5 and Lorenzo Lodola 3 1 Department of Oncohaematology, Radiotherapy Unit, Fondazione IRCCS Policlinico San Matteo, Viale Golgi 19, 27100 Pavia, Italy 2 Department of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, Via Ferrata 9, 27100 Pavia, Italy 3 Department of Oncohaematology, Nuclear Medicine Unit, Fondazione IRCCS Policlinico San Matteo, Viale Golgi 19, 27100 Pavia, Italy 4 Scuola Universitaria Superiore IUSS Pavia, Pavia, Italy 5 National Centre for Oncological Hadrontherapy (CNAO), Via Campeggi 53, 27100 Pavia, Italy 6 Nuclear Medicine Research Department, IASON GmbH, Graz, Austria Correspondence should be addressed to Carlo Aprile; c.aprile@smatteo.pv.it Received 29 July 2016; Revised 10 November 2016; Accepted 26 December 2016; Published 15 January 2017 Academic Editor: Ralf Schirrmacher Copyright © 2017 Francesca Pasi et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Te diferential diagnosis between recurrence of gliomas or brain metastases and this phenomenon is important in order to choose the best therapy and predict the prognosis but is still a big problem for physicians. Te new emerging MRI, CT, and PET diagnostic modalities still lack sufcient accuracy. Radiolabeled choline and amino acids have been reported to show great tumor specifcity. We studied the uptake kinetics of [ 18 F]fuoromethyl-choline (FCH) and O-(2-[ 18 F]fuoroethyl)-L-tyrosine (FET) by the T98G human glioblastoma cells from 20 to 120 min afer irradiation either with photons at 2-10-20 Gy or with carbon ions at 2 Gy (at the National Centre for Oncological Hadrontherapy (CNAO), Pavia, Italy). We also evaluated the cell death and morphology changes induced by radiation treatment. Both FET and FCH are able to trace tumor behavior in terms of higher uptake for increased doses of radiation treatment, due to the upregulation of cells attempts to repair nonlethal damage. Our data suggest that both FCH and FET could be useful to analyze the metabolic pathways of glioblastoma cells before and afer radiotherapy. Physicians will have to consider the diferent kinetics pathways of uptake concerning the two radiopharmaceuticals. 1. Introduction Te diferential diagnosis between recurrence of gliomas and brain metastases and the phenomenon of radiation necrosis plays an important role in both therapeutic and prognostic settings. Te distinction between tumor recur- rence and radionecrosis is important in order to choose the best subsequent therapy and prognosis is guided by the cause of progression. Necrosis is an important histological feature of glial tumors. Tumor necrosis is ischemic in nature, due to an insufcient blood supply [1]. Te diferential diagnosis is complicated by the fact that late radionecrosis appears at various times afer treatment, from 6 months up to several years [2]. Moreover, radionecrosis phenomenon is observable without the direct involvement of the brain in the feld of radiation (bystander efect, e.g., head and neck cancer irradiated with hadrons). Nowadays, despite the enormous improvement of diagnostic modalities, including the vari- ous applications of MRI, CT, and PET, the diagnosis and grading of primary brain tumours lack sufcient accuracy. Tis is more relevant when recurrence afer therapy, early neuroinfammation [3], or late radionecrosis is concerned [4]. Despite the technological advances and new MR inves- tigable parameters [5], there is a wide area that does not allow the reasonable accuracy that the clinicians need. Also, PET radiopharmaceuticals ( 11 C-METH, 18 F-FET, 18 F-FCH, and 18 F-DOPA) have limitations mainly in terms of speci- fcity, although the dynamic investigation, only possible with Hindawi Contrast Media & Molecular Imaging Volume 2017, Article ID 6491674, 8 pages https://doi.org/10.1155/2017/6491674