title: Additional lesions detected in therapeutic scans with 177Lu-DOTATATE reflect higher affinity of 177Lu-DOTATATE for somatostatin receptors.
abstract: OBJECTIVE
  Peptide receptor-targeted radionuclide therapy (PRRT) of somatostatin receptor (SR)-expressing neuroendocrine tumors (NETs) has become an established therapeutic option in patients with advanced NETs. The aim of this study was to compare the lesion detection rate of (99m)Tc-EDDA/HYNIC-TOC, a newly developed tracer for NET imaging, with (177)Lu-DOTATATE used for PRRT.
  
  
  METHODS
  8 patients (4 women, 4 men, age range 46-76 years) with histologically proven NETs, who showed high SR loads by (99m)Tc-EDDA/HYNIC-TOC scintigraphy, were treated with (177)Lu-DOTATATE. After treatment, all patients were subjected to whole-body scintigraphy with additional low-dose single-photon emission computed tomography (SPECT-CT) of the chest and abdomen.
  
  
  RESULTS
  All patients demonstrated (177)Lu-DOTATATE accumulation in all lesions previously detected by (99m)Tc- EDDA/HYNIC-TOC scintigraphy. Three patients showed additional lesions in the liver and lungs.
  
  
  CONCLUSIONS
  SPECT-CT after (177)Lu-DOTATATE therapy may be helpful in detecting additional lesions not seen using (99m)Tc-EDDA/HYNIC-TOC. This could reflect the broader affinity of (177)Lu-DOTATATE for SRs compared with (99m)Tc-EDDA/HYNIC-TOC.
authors.affiliation: Institute of Nuclear Medicine with PET Center, Wilhelminenspital, Montleartstrasse 37, Vienna, Austria.
authors.forename: Siroos
authors.initials: S
authors.lastname: Mirzaei
authors.forename: Brigitte
authors.initials: B
authors.lastname: Bastati
authors.forename: Rainer W
authors.initials: RW
authors.lastname: Lipp
authors.forename: Peter
authors.initials: P
authors.lastname: Knoll
authors.forename: Niklas
authors.initials: N
authors.lastname: Zojer
authors.forename: Heinz
authors.initials: H
authors.lastname: Ludwig
mesh_terms: D000368:Aged; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000000981:diagnostic imaging* / Q000378:metabolism*; D015282:Octreotide / Q000031:analogs & derivatives* / Q000378:metabolism / Q000627:therapeutic use; D009942:Organometallic Compounds / Q000378:metabolism / Q000627:therapeutic use*; D015609:Organotechnetium Compounds / Q000378:metabolism; D019275:Radiopharmaceuticals / Q000627:therapeutic use; D017481:Receptors, Somatostatin / Q000378:metabolism*; D012680:Sensitivity and Specificity; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014057:Tomography, X-Ray Computed
chemical_list: D009942:Organometallic Compounds; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D017481:Receptors, Somatostatin; C526854:technetium Tc 99m (EDDA-HYNIC)octreotate; C447941:lutetium Lu 177 dotatate; D015282:Octreotide