title: Preclinical imaging of therapy response using metabolic and apoptosis molecular imaging.
abstract: OBJECTIVE
  Early after therapy, 2-deoxy-2-[(18)F]fluoro-D-glucose ([(18)F]FDG) imaging is not always reliable due to the influx of inflammatory cells while apoptosis imaging offers a direct and early measurement of therapy effects. This study uses an improved apoptosis probe ((99m)Tc-hAnxA5) in combination with [(18)F]FDG imaging to evaluate therapy response.
  
  
  METHODS
  Daudi tumor tissue was implanted in the spleen of SCID mice. Treatment was performed with adriamycin and cyclophosphamide. Sequential [(18)F]FDG-positron emission tomography (PET) was acquired over 6 days and (99m)Tc-hAnxA5-SPECT was performed before and 1 day after therapy.
  
  
  RESULTS
  On day 1, therapy induced apoptosis was visualized with (99m)Tc-hAnxA5 without a measurable change in [(18)F]FDG uptake. [(18)F]FDG uptake decreased significantly on day 3 and was even more pronounced on day 6.
  
  
  CONCLUSIONS
  In this preclinical model, (99m)Tc-hAnxA5 imaging was able to detect apoptosis before metabolic changes were measured. These results confirm the value of apoptosis imaging for therapy response and give more insight in [(18)F]FDG imaging and its parameters to evaluate response.
authors.affiliation: Department of Nuclear Medicine, University Hospital Gasthuisberg Leuven, Leuven, Belgium.
authors.forename: Marijke
authors.initials: M
authors.lastname: De Saint-Hubert
authors.forename: Huijun
authors.initials: H
authors.lastname: Wang
authors.forename: Ellen
authors.initials: E
authors.lastname: Devos
authors.forename: Kathleen
authors.initials: K
authors.lastname: Vunckx
authors.forename: Lin
authors.initials: L
authors.lastname: Zhou
authors.forename: Chris
authors.initials: C
authors.lastname: Reutelingsperger
authors.forename: Alfons
authors.initials: A
authors.lastname: Verbruggen
authors.forename: Luc
authors.initials: L
authors.lastname: Mortelmans
authors.forename: Yicheng
authors.initials: Y
authors.lastname: Ni
authors.forename: Felix M
authors.initials: FM
authors.lastname: Mottaghy
mesh_terms: D000818:Animals; D017209:Apoptosis; D045744:Cell Line, Tumor; D004195:Disease Models, Animal; D006801:Humans; D008223:Lymphoma / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology; D008279:Magnetic Resonance Imaging; D051379:Mice; D016513:Mice, SCID; D049268:Positron-Emission Tomography; D015899:Tomography, Emission-Computed, Single-Photon