title: 68Ga-DOTATATE PET/CT, 99mTc-HYNIC-octreotide SPECT/CT, and whole-body MR imaging in detection of neuroendocrine tumors: a prospective trial.
abstract: There are different metabolic imaging methods, various tracers, and emerging anatomic modalities to stage neuroendocrine tumor (NET). We aimed to compare NET lesion detectability among (99m)Tc-hydrazinonicotinamide (HYNIC)-octreotide (somatostatin receptor scintigraphy [SSRS]) SPECT/CT, (68)Ga-DOTATATE PET/CT, and whole-body diffusion-weighted MR imaging (WB DWI).
  
  
  METHODS
  Nineteen consecutive patients (34-77 y old; mean, 54.3 ± 10.4 y old; 10 men and 9 women) underwent SSRS SPECT/CT, (68)Ga-DOTATATE PET/CT, and WB DWI. Images were acquired with a maximum interval of 3 mo between them and were analyzed with masking by separate teams. Planar whole-body imaging and SPECT/CT were performed from thorax to pelvis using a double-head 16-slice SPECT/CT scanner 4 h after injection of 111-185 MBq of (99m)Tc-HYNIC-octreotide. (68)Ga-DOTATATE PET/CT was performed from head to feet using a 16-slice PET/CT scanner 45 min after injection of 185 MBq of tracer. WB DWI was performed in the coronal plane using a 1.5-T scanner and a body coil. The standard method of reference for evaluation of image performance was undertaken: consensus among investigators at the end of the study, clinical and imaging follow-up, and biopsy of suggestive lesions.
  
  
  RESULTS
  McNemar testing was applied to evaluate the detectability of lesions using (68)Ga-DOTATATE PET/CT in comparison to SSRS SPECT/CT and WB DWI: a significant difference in detectability was noted for pancreas (P = 0.0455 and P = 0.0455, respectively), gastrointestinal tract (P = 0.0455 and P = 0.0455), and bones (P = 0.0082 and P = 0.0082). Two unknown primary lesions were identified solely by (68)Ga-DOTATATE PET/CT. (68)Ga-DOTATATE PET/CT, SSRS SPECT/CT, and WB DWI demonstrated, respectively, sensitivities of 0.96, 0.60, and 0.72; specificities of 0.97, 0.99, and 1.00; positive predictive values of 0.94, 0.96, and 1.00; negative predictive values of 0.98, 0.83, and 0.88; and accuracies of 0.97, 0.86, and 0.91.
  
  
  CONCLUSIONS
  (68)Ga PET/CT seems to be more sensitive for detection of well-differentiated NET lesions, especially for bone and unknown primary lesions. NET can be staged with (68)Ga-DOTATATE PET/CT. WB DWI is an efficient new method with high accuracy and without ionizing radiation exposure. SSRS SPECT/CT should be used only when (68)Ga-DOTATATE PET/CT and WB DWI are not available.
authors.affiliation: Division of Nuclear Medicine and PET/CT, Sirio Libanes Hospital, São Paulo, Brazil.
authors.forename: Elba Cristina Sá de Camargo
authors.initials: EC
authors.lastname: Etchebehere
authors.affiliation: Division of Nuclear Medicine and PET/CT, Sirio Libanes Hospital, São Paulo, Brazil.
authors.forename: Allan
authors.initials: A
authors.lastname: de Oliveira Santos
authors.affiliation: Oncology Center, Sirio Libanes Hospital, São Paulo, Brazil; and.
authors.forename: Brenda
authors.initials: B
authors.lastname: Gumz
authors.affiliation: Division of Nuclear Medicine and PET/CT, Sirio Libanes Hospital, São Paulo, Brazil.
authors.forename: Andreia
authors.initials: A
authors.lastname: Vicente
authors.affiliation: Oncology Center, Sirio Libanes Hospital, São Paulo, Brazil; and.
authors.forename: Paulo Ghem
authors.initials: PG
authors.lastname: Hoff
authors.affiliation: Division of Radiology, Sirio Libanes Hospital, São Paulo, Brazil.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Corradi
authors.affiliation: Division of Nuclear Medicine and PET/CT, Sirio Libanes Hospital, São Paulo, Brazil.
authors.forename: Wilson André
authors.initials: WA
authors.lastname: Ichiki
authors.affiliation: Division of Nuclear Medicine and PET/CT, Sirio Libanes Hospital, São Paulo, Brazil.
authors.forename: José Geraldo
authors.initials: JG
authors.lastname: de Almeida Filho
authors.affiliation: Division of Radiology, Sirio Libanes Hospital, São Paulo, Brazil.
authors.forename: Saulo
authors.initials: S
authors.lastname: Cantoni
authors.affiliation: Division of Nuclear Medicine and PET/CT, Sirio Libanes Hospital, São Paulo, Brazil elba.etchebehere@hsl.org.br.
authors.forename: Edwaldo Eduardo
authors.initials: EE
authors.lastname: Camargo
authors.affiliation: Oncology Center, Sirio Libanes Hospital, São Paulo, Brazil; and.
authors.forename: Frederico Perego
authors.initials: FP
authors.lastname: Costa
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D001706:Biopsy; D005260:Female; D006801:Humans; D006834:Hydrazines; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000000981:diagnostic imaging* / Q000473:pathology*; D009539:Nicotinic Acids; D015282:Octreotide; D009942:Organometallic Compounds; D049268:Positron-Emission Tomography / Q000379:methods*; D011446:Prospective Studies; D013667:Technetium; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods*; D051598:Whole Body Imaging / Q000379:methods*
chemical_list: C120392:6-hydrazinopyridine-3-carboxylic acid; D006834:Hydrazines; D009539:Nicotinic Acids; D009942:Organometallic Compounds; D013667:Technetium; C513399:gallium Ga 68 dotatate; D015282:Octreotide
keywords: 68Ga-DOTATATE PET/CT; 99mTc-HYNIC-octreotide SPECT/CT; MRI; PET/CT; SPECT/CT; neuroendocrine tumor