title: New radiological clues in the diagnosis of spindle cell oncocytoma of the adenohypophysis.
abstract: OBJECTIVE
  To present three new cases of spindle cell oncocytoma (SCO) from a single centre and to identify new radiological clues in the diagnosis of SCO according to the information obtained from the cases presented.
  
  
  METHODS
  Three adults with SCO confirmed at histopathology were retrospectively reviewed. The medical records, imaging findings, operative notes, and histopathology findings for each patient were recorded. Magnetic resonance imaging (MRI) findings were evaluated, including tumour localisation, tumour size, signal intensity, imaging features on T1-weighted and T2-weighted images, and contrast enhancement characteristics. The study protocol was approved by the institutional review board. Informed consent was obtained from each patient.
  
  
  RESULTS
  T1-weighted imaging (WI) and T2WI demonstrated millimetric hypointense foci and linear signal void areas in all lesions. Consistent with the hypervascular features of the tumour, intense contrast enhancement was observed during the early stages of dynamic contrast enhanced (DCE) MRI. Linear signal void areas showed contrast enhancement, but some of the hypointense millimetric foci remained without contrast enhancement.
  
  
  CONCLUSIONS
  Although the radiological findings and preoperative diagnosis of SCO have been reported to be non-specific and impossible, respectively, in the literature, the characteristics of MRI and different patterns of contrast enhancement can help in recognising this rare entity. This article represents a single institution case series of SCOs and also includes the first description of a correlation of the histopathological findings with radiological findings and new clues in the differential diagnosis of SCOs. We described these new radiological clues as "Hasiloglu's Signs".
authors.affiliation: Department of Radiology, Istanbul University, Cerrahpasa Medical Faculty, Kocamustafapasa, Istanbul, Turkey. Electronic address: zhasiloglu@gmail.com.
authors.forename: Z I
authors.initials: ZI
authors.lastname: Hasiloglu
authors.affiliation: Department of Radiology, Istanbul University, Cerrahpasa Medical Faculty, Kocamustafapasa, Istanbul, Turkey.
authors.forename: E
authors.initials: E
authors.lastname: Ure
authors.affiliation: Department of Pathology, Istanbul University, Cerrahpasa Medical Faculty, Kocamustafapasa, Istanbul, Turkey.
authors.forename: N
authors.initials: N
authors.lastname: Comunoglu
authors.affiliation: Department of Neurosurgery, Istanbul University, Cerrahpasa Medical Faculty, Kocamustafapasa, Istanbul, Turkey.
authors.forename: N
authors.initials: N
authors.lastname: Tanriover
authors.affiliation: Department of Pathology, Istanbul University, Cerrahpasa Medical Faculty, Kocamustafapasa, Istanbul, Turkey.
authors.forename: B
authors.initials: B
authors.lastname: Oz
authors.affiliation: Department of Neurosurgery, Istanbul University, Cerrahpasa Medical Faculty, Kocamustafapasa, Istanbul, Turkey.
authors.forename: N
authors.initials: N
authors.lastname: Gazioglu
authors.affiliation: Department of Radiology, Istanbul University, Cerrahpasa Medical Faculty, Kocamustafapasa, Istanbul, Turkey.
authors.forename: I
authors.initials: I
authors.lastname: Mihmanli
mesh_terms: D018249:Adenoma, Oxyphilic / Q000000981:diagnostic imaging* / Q000473:pathology*; D000328:Adult; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010911:Pituitary Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D047368:Tumor Burden