title: High-Resolution Magnetic Resonance Imaging Can Reliably Detect Orbital Tumor Recurrence after Enucleation in Children with Retinoblastoma.
abstract: OBJECTIVE
  Orbital tumor recurrence is a rare but serious complication in children with retinoblastoma, leading to a high risk of metastasis and death. Therefore, we assume that these recurrences have to be detected and treated as early as possible. Preliminary studies used magnetic resonance imaging (MRI) to evaluate postsurgical findings in the orbit. In this study, we assessed the diagnostic accuracy of high-resolution MRI to detect orbital tumor recurrence in children with retinoblastoma in a large study cohort.
  
  
  METHODS
  Consecutive retrospective study (2007-2013) assessing MRI findings after enucleation.
  
  
  METHODS
  A total of 103 MRI examinations of 55 orbits (50 children, 27 male/23 female, mean age 16.3±12.4 months) with a median time of 8 months (range, 0-93) after enucleation for retinoblastoma.
  
  
  METHODS
  High-resolution MRI using orbital surface coils was performed on 1.5 Tesla MRI systems to assess abnormal orbital findings.
  
  
  METHODS
  Five European experts in retinoblastoma imaging evaluated the MRI examinations regarding the presence of abnormal orbital gadolinium enhancement and judged them as "definitive tumor," "suspicious of tumor," "postsurgical condition/scar formation," or "without pathologic findings." The findings were correlated to histopathology (if available), MRI, and clinical follow-up.
  
  
  RESULTS
  Abnormal orbital enhancement was a common finding after enucleation (100% in the first 3 months after enucleation, 64.3% >3 years after enucleation). All histopathologically confirmed tumor recurrences (3 of 55 orbits, 5.5%) were correctly judged as "definitive tumor" in MRI. Two orbits from 2 children rated as "suspicious of tumor" received intravenous chemotherapy without histopathologic confirmation; further follow-up (67 and 47 months) revealed no sign of tumor recurrence. In 90.2%, no tumor was suspected on MRI, which was clinically confirmed during follow-up (median follow-up after enucleation, 45 months; range, 8-126).
  
  
  CONCLUSIONS
  High-resolution MRI with orbital surface coils may reliably distinguish between common postsurgical contrast enhancement and orbital tumor recurrence, and therefore may be a useful tool to evaluate orbital tumor recurrence after enucleation in children with retinoblastoma. We recommend high-resolution MRI as a potential screening tool for the orbit in children with retinoblastoma to exclude tumor recurrence, especially in high-risk patients within the critical first 2 years after enucleation.
authors.affiliation: Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany. Electronic address: selma.sirin@uk-essen.de.
authors.forename: Selma
authors.initials: S
authors.lastname: Sirin
authors.affiliation: Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Marcus C
authors.initials: MC
authors.lastname: de Jong
authors.affiliation: Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Pim
authors.initials: P
authors.lastname: de Graaf
authors.affiliation: Department of Radiology, Institut Curie, Paris, France.
authors.forename: Hervé J
authors.initials: HJ
authors.lastname: Brisse
authors.affiliation: Unit of Diagnostic and Therapeutic Neuroradiology, Department of Neurosciences, Azienda Ospedaliera Universitaria Senese, Siena, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Galluzzi
authors.affiliation: Department of Radiology, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland.
authors.forename: Philippe
authors.initials: P
authors.lastname: Maeder
authors.affiliation: Department of Ophthalmology, University Hospital Essen, Essen, Germany.
authors.forename: Norbert
authors.initials: N
authors.lastname: Bornfeld
authors.affiliation: Department of Ophthalmology, University Hospital Essen, Essen, Germany.
authors.forename: Eva
authors.initials: E
authors.lastname: Biewald
authors.affiliation: Department of Pathology and Neuropathology, University Hospital Essen, Essen, Germany.
authors.forename: Klaus A
authors.initials: KA
authors.lastname: Metz
authors.affiliation: Department of Pediatric Hematology and Oncology, University Hospital Essen, Essen, Germany.
authors.forename: Petra
authors.initials: P
authors.lastname: Temming
authors.affiliation: Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Jonas A
authors.initials: JA
authors.lastname: Castelijns
authors.affiliation: Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany.
authors.forename: Sophia L
authors.initials: SL
authors.lastname: Goericke
mesh_terms: D002675:Child, Preschool; D003287:Contrast Media; D015353:Eye Enucleation; D005260:Female; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis*; D009918:Orbital Neoplasms / Q000175:diagnosis* / Q000556:secondary; D015203:Reproducibility of Results; D019572:Retinal Neoplasms / Q000473:pathology / Q000601:surgery*; D012175:Retinoblastoma / Q000556:secondary / Q000601:surgery*; D012189:Retrospective Studies
chemical_list: D003287:Contrast Media