title: Concurrent SPECT/PET-CT imaging as a method for tracking adoptively transferred T-cells in vivo.
abstract: BACKGROUND
  The ability of T-cells to traffic to and penetrate tumors impacts the clinical efficacy of T-cell therapy therefore methods to track transferred T-cells in vivo are needed. In this preliminary report, we evaluated the use of concurrent SPECT/PET-CT imaging to monitor the egress of HER-2/neu specific T-cells in a breast cancer patient with extensive bone-only metastatic disease.
  
  
  RESULTS
  Indium (In-111) labeled T-cells demonstrated similar or greater viability than unlabeled T-cells at either a low or high dose of In-111 over a 24-h incubation period in vitro. The function of labeled or unlabeled T-cells was not significantly different (p > 0.05) at either dose. T-cells trafficked to all sites of metastatic disease and infiltrated the tumor as assessed by SPECT imaging. In-111 uptake at 24 h after infusion varied from 3.8 (right proximal humerus) to 6.3 (right sacrum) background corrected counts per pixel and remained elevated at 48 h. Concurrent PET-CT imaging demonstrated a fluorodeoxyglucose flare, measured by increase in tumor site uptake as high as 32 % and at most sites of disease at 48 h. This flare was associated with focal pain after T-cell infusion at metastatic sites. The patient had stable disease for 18 months after completion of T-cell therapy.
  
  
  CONCLUSIONS
  Concurrent SPECT/PET-CT imaging, over a 48-h period after T-cell infusion, provided evidence of T-cell homing to all disease sites as well as a tumor metabolism flare response. This technique may be useful for monitoring T-cell trafficking after autologous as well as chimeric antigen receptor T-cell infusion.
  
  
  BACKGROUND
  Trial registered at ClinicalTrials.gov registration number NCT00791037, registered 13 November 2008.
authors.affiliation: Tumor Vaccine Group, Center for Translational Medicine in Women's Health, University of Washington, Seattle, WA 98109 USA.
authors.forename: Sasha E
authors.initials: SE
authors.lastname: Stanton
authors.affiliation: Department of Radiology, University of Alabama at Birmingham, Birmingham, AL 35249 USA.
authors.forename: Janet F
authors.initials: JF
authors.lastname: Eary
authors.affiliation: Tumor Vaccine Group, Center for Translational Medicine in Women's Health, University of Washington, Seattle, WA 98109 USA.
authors.forename: Edmond A
authors.initials: EA
authors.lastname: Marzbani
authors.affiliation: Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 USA.
authors.forename: David
authors.initials: D
authors.lastname: Mankoff
authors.affiliation: Tumor Vaccine Group, Center for Translational Medicine in Women's Health, University of Washington, Seattle, WA 98109 USA.
authors.forename: Lupe G
authors.initials: LG
authors.lastname: Salazar
authors.affiliation: Tumor Vaccine Group, Center for Translational Medicine in Women's Health, University of Washington, Seattle, WA 98109 USA.
authors.forename: Doreen
authors.initials: D
authors.lastname: Higgins
authors.affiliation: Tumor Vaccine Group, Center for Translational Medicine in Women's Health, University of Washington, Seattle, WA 98109 USA.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Childs
authors.affiliation: Tumor Vaccine Group, Center for Translational Medicine in Women's Health, University of Washington, Seattle, WA 98109 USA.
authors.forename: Jessica
authors.initials: J
authors.lastname: Reichow
authors.affiliation: Tumor Vaccine Group, Center for Translational Medicine in Women's Health, University of Washington, Seattle, WA 98109 USA.
authors.forename: Yushe
authors.initials: Y
authors.lastname: Dang
authors.affiliation: Tumor Vaccine Group, Center for Translational Medicine in Women's Health, University of Washington, Seattle, WA 98109 USA.
authors.forename: Mary L
authors.initials: ML
authors.lastname: Disis
keywords: Adoptive T-cell therapy; FDG; HER2; Indium-111 labeled; PET-CT; SPECT; breast cancer