title: Outcome of small lung nodules missed on hybrid PET/MRI in patients with primary malignancy.
abstract: OBJECTIVE
  To assess outcomes of lung nodules missed on simultaneous positron emission tomography and magnetic resonance imaging (PET/MRI) compared to the reference standard PET and computed tomography (PET/CT) in patients with primary malignancy.
  
  
  METHODS
  In all, 208 patients with primary malignancy undergoing clinically indicated (18F) fluorodeoxyglucose (FDG) PET/CT followed by PET/MRI were independently reviewed by two readers. Upon review of the thoracic station on PET/MRI and PET/CT, 89 non-FDG avid small lung nodules in 43 patients were detected (by reader 1) only on the CT component of the PET/CT but were not identified on PET/MRI. Overall, 84 of these 89 nodules were examined on follow-up imaging with PET/CT or chest CT. The remaining five nodules had no follow-up imaging but had remote imaging available for comparison.
  
  
  RESULTS
  Among the 84 nodules with follow-up, three nodules (3%) in one patient progressed, 10 (12%) nodules partially/completely resolved, whereas 71 nodules (85%) remained stable. The five nodules without follow-up were all stable since prior imaging of over 21 months.
  
  
  CONCLUSIONS
  The vast majority (97%) of small non-FDG avid lung nodules missed on PET/MRI either resolved or remained stable on follow-up, suggestive of benignity. PET/MRI remains a viable alternative imaging modality in oncology patients, despite its low sensitivity in detecting small lung nodules.
authors.affiliation: New York University School of Medicine, Department of Radiology, New York, New York, USA.
authors.forename: Roy A
authors.identifier: http://orcid.org/0000-0001-7561-6983
authors.initials: RA
authors.lastname: Raad
authors.affiliation: New York University School of Medicine, Department of Radiology, New York, New York, USA.
authors.forename: Kent P
authors.initials: KP
authors.lastname: Friedman
authors.affiliation: New York University School of Medicine, Department of Radiology, New York, New York, USA.
authors.forename: Laura
authors.initials: L
authors.lastname: Heacock
authors.affiliation: New York University School of Medicine, Department of Radiology, New York, New York, USA.
authors.forename: Fabio
authors.initials: F
authors.lastname: Ponzo
authors.affiliation: New York University School of Medicine, Department of Radiology, New York, New York, USA.
authors.forename: Amy
authors.initials: A
authors.lastname: Melsaether
authors.affiliation: New York University School of Medicine, Department of Radiology, New York, New York, USA.
authors.forename: Hersh
authors.initials: H
authors.lastname: Chandarana
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging / Q000473:pathology; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D017063:Outcome Assessment, Health Care; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: PET/CT; PET/MRI; lung; malignancy; nodules