title: 68Ga-DOTANOC PET/CT allows somatostatin receptor imaging in idiopathic pulmonary fibrosis: preliminary results.
abstract: Interstitial lung diseases include different clinical entities with variable prognoses. Idiopathic pulmonary fibrosis (IPF), the most common, presents the most severe outcome (death within 3-5 y), whereas nonspecific interstitial pneumonia (NSIP) shows a more indolent progression. Preclinical evidence of somatostatin receptor (SSTR) expression on fibroblasts in vitro and in lung fibrosis murine models, coupled with the longer survival of mice with fibrotic lungs treated with agents blocking SSTR, supports the hypothesis of imaging fibroblast activity in vivo by visualization of SSTR with (68)Ga-DOTANOC PET/CT. The aim of this study was to evaluate (68)Ga-DOTANOC PET/CT in patients with IPF and NSIP.
  
  
  METHODS
  Seven IPF patients and 7 NSIP patients were included in the study. (68)Ga-DOTANOC PET/CT and high-resolution CT (HRCT) were performed in all cases by following a standard procedure. PET/CT results were compared with disease sites and extent on HRCT.
  
  
  RESULTS
  In IPF, (68)Ga-DOTANOC uptake was peripheral, subpleural, and directly correlated with pathologic areas on HRCT (subpleural/reticular fibrosis, honeycombing). NSIP patients showed fainter tracer uptake, whereas corresponding HRCT showed areas of ground-glass opacity and rare fibrotic changes. Only IPF patients showed a linear correlation between maximal SUV and disease extent quantified both automatically (Q) (IPF: P = 0.002, R = 0.93) and using the visual score (Spearman ρ = 0.46, P = 0.0001). Q directly correlated with percentage carbon monoxide diffusing capacity in IPF (P = 0.03, R = 0.79) and NSIP (P = 0.05, R = 0.94), whereas maximal SUV did not present any correlation with percentage carbon monoxide diffusing capacity.
  
  
  CONCLUSIONS
  Our preliminary data show that (68)Ga-DOTANOC PET/CT demonstrates SSTR overexpression in IPF patients; this may prove interesting for the evaluation of novel treatments with somatostatin analogs.
authors.affiliation: Nuclear Medicine, Azienda Ospedaliero-Universitaria di Bologna, S Orsola-Malpighi Hospital, Bologna, Italy. valentina.ambrosini@aosp.bo.it
authors.forename: Valentina
authors.initials: V
authors.lastname: Ambrosini
authors.forename: Maurizio
authors.initials: M
authors.lastname: Zompatori
authors.forename: Fiorella
authors.initials: F
authors.lastname: De Luca
authors.forename: D'Errico
authors.initials: D
authors.lastname: Antonia
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Allegri
authors.forename: Cristina
authors.initials: C
authors.lastname: Nanni
authors.forename: Deborah
authors.initials: D
authors.lastname: Malvi
authors.forename: Eva
authors.initials: E
authors.lastname: Tonveronachi
authors.forename: Luca
authors.initials: L
authors.lastname: Fasano
authors.forename: Mario
authors.initials: M
authors.lastname: Fabbri
authors.forename: Stefano
authors.initials: S
authors.lastname: Fanti
mesh_terms: D000368:Aged; D001706:Biopsy; D005260:Female; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D009942:Organometallic Compounds / Q000008:administration & dosage; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D011653:Pulmonary Diffusing Capacity; D011658:Pulmonary Fibrosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D019275:Radiopharmaceuticals / Q000008:administration & dosage; D017481:Receptors, Somatostatin / Q000378:metabolism*; D012129:Respiratory Function Tests; D014055:Tomography, Emission-Computed
chemical_list: C504894:68Ga-DOTANOC; D009942:Organometallic Compounds; D019275:Radiopharmaceuticals; D017481:Receptors, Somatostatin