AUTHOR=Breun Maria , Monoranu Camelia M. , Kessler Almuth F. , Matthies Cordula , Löhr Mario , Hagemann Carsten , Schirbel Andreas , Rowe Steven P. , Pomper Martin G. , Buck Andreas K. , Wester Hans-Jürgen , Ernestus Ralf-Ingo , Lapa Constantin 

TITLE=[68Ga]-Pentixafor PET/CT for CXCR4-Mediated Imaging of Vestibular Schwannomas

JOURNAL=Frontiers in Oncology

VOLUME=9

YEAR=2019

URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2019.00503

DOI=10.3389/fonc.2019.00503

ISSN=2234-943X

ABSTRACT=<p>We have recently demonstrated CXCR4 overexpression in vestibular schwannomas (VS). This study investigated the feasibility of CXCR4-directed positron emission tomography/computed tomography (PET/CT) imaging of VS using the radiolabeled chemokine ligand [<sup>68</sup>Ga]Pentixafor.</p><p><bold>Methods:</bold> 4 patients with 6 primarily diagnosed or pre-treated/observed VS were enrolled. All subjects underwent [<sup>68</sup>Ga]Pentixafor PET/CT prior to surgical resection. Images were analyzed visually and semi-quantitatively for CXCR4 expression including calculation of tumor-to-background ratios (TBR). Immunohistochemistry served as standard of reference in three patients.</p><p><bold>Results:</bold> [<sup>68</sup>Ga]Pentixafor PET/CT was visually positive in all cases. SUV<sub>mean</sub> and SUV<sub>max</sub> were 3.0 ± 0.3 and 3.8 ± 0.4 and TBR<sub>mean</sub> and TBR<sub>max</sub> were 4.0 ± 1.4 and 5.0 ± 1.7, respectively. Histological analysis confirmed CXCR4 expression in tumors.</p><p><bold>Conclusion:</bold> Non-invasive imaging of CXCR4 expression using [<sup>68</sup>Ga]Pentixafor PET/CT of VS is feasible and could prove useful for <italic>in vivo</italic> assessment of CXCR4 expression.</p>