@article{LewisHabringerKircheretal.2021,
  author    = {Lewis, Richard and Habringer, Stefan and Kircher, Malte and Hefter, Maike and Peuker, Caroline Anna and Werner, Rudolf and Ademaj-Kospiri, Val{\"e}za and G{\"a}ble, Alexander and Weber, Wolfgang and Wester, Hans-J{\"u}rgen and Buck, Andreas and Herhaus, Peter and Lapa, Constantin and Keller, Ulrich},
  title     = {Investigation of spleen CXCR4 expression by [68Ga]Pentixafor PET in a cohort of 145 solid cancer patients},
  series = {EJNMMI Research},
  volume    = {11},
  journal   = {EJNMMI Research},
  doi       = {10.1186/s13550-021-00822-6},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-363820},
  year      = {2021},
  abstract  = {Background The chemokine receptor CXCR4 is frequently overexpressed and associated with adverse prognosis in most hematopoietic malignancies and solid cancers. Recently, CXCR4 molecular imaging using the CXCR4-specific positron emission tomography (PET) tracer Pentixafor ([68Ga]Pentixafor) has become a well-established method to non-invasively measure CXCR4 expression in vivo. In previous Pentixafor imaging studies, highly variable CXCR4 tracer uptake to the spleen was observed. Results We investigated the hypothesis that enhanced spleen [68Ga]Pentixafor uptake and thus CXCR4 expression in patients with solid tumors would indicate an activated spleen state and/or an association with clinical and prognostic features and survival parameters. In this retrospective study, [68Ga]Pentixafor-PET images and patient records of 145 solid tumor patients representing 27 cancer entities were investigated for an association of spleen [68Ga]Pentixafor uptake and clinical characteristics and outcome. Based on this assessment, we did not observe differences in clinical outcomes, measured by progression-free survival, overall survival and remission status neither within the entire cohort nor within subgroups of adrenal cancer, desmoplastic small round cell tumor, neuroendocrine tumors, non-small cell lung cancer, small cell lung cancer and pancreatic adenocarcinoma patients. No tumor entity showed especially high levels of spleen [68Ga]Pentixafor uptake compared to others or a control cohort. However, when investigating laboratory parameters, there was a positive correlation of high spleen [68Ga]Pentixafor uptake with leukocyte and/or platelet counts in neuroendocrine tumors, non-small cell lung cancer and small cell lung cancer. Conclusion Spleen [68Ga]Pentixafor uptake was not associated with stage of disease and clinical outcomes in solid tumor patients. We identified positively associated platelet and/or leukocyte counts with spleen [68Ga]Pentixafor uptake in neuroendocrine tumors, non-small cell lung cancer and small cell lung cancer, suggesting that splenic CXCR4 expression could possibly play a role in systemic immunity/inflammation in some types of solid tumors or a subgroup of patients within solid tumor entities.},
  language  = {en}
}