title: Three-dimensional volumetric measurements in defining endoscope-guided giant adenoma surgery outcomes.
abstract: OBJECTIVE
  Maximum two-dimensional (2D) diameter has been used to define giant pituitary adenoma (GPA) surgery outcomes as has volume using an ellipsoid approximation of volumetrics. Cross sectional length can be measured in several different planes. We sought to compare the accuracy of different 2D cross sectional measurements with the 3D volumetric measurements for predicting GPA surgery outcomes.
  
  
  METHODS
  Retrospective analysis was performed on a prospectively collected database. Tumors with >3 cm diameter were identified and classified based on maximal cross sectional measurements in three separate co-axial planes, i.e. transverse (TV), antero-posterior (AP) and cranio-caudal (CC). Volume was calculated using both MRI-guided volumetrics and an ellipsoid approximation (TV × AP × CC/2). Univariate and multivariate analysis was used to evaluate the relationship between cross sectional and volumetric data and extent of resection (EOR).
  
  
  RESULTS
  In 62 subjects, median tumor volume using 3D volumetrics was 13.74 cm(3), which was overestimated by 16 % by the ellipsoid calculation (p = 0.0029), particularly for tumors >20 cm(3). Gross total resection (GTR) was 46.7 % and median EOR was 99.57 %. At 22-month follow-up, visual and anterior pituitary functions were stable (90 %) or improved (87 %). Pre-operative tumor volume >10 cm(3) (p = 0.02) and Knosp grade 3-4 (p = 0.04) were independent predictors of EOR. Knosp grade 3-4 (p < 0.0001), TV measurement >4 cm (p = 0.007) and maximum cross sectional length >4 cm (p = 0.04) were predictors of not achieving GTR. Only TV measurement (p = 0.02) predicted permanent diabetes insipidis. The smallest significant thresholds for predicting decreased GTR were TV measurement >25 mm, AP measurement >35 mm and volume >19 cm(3).
  
  
  CONCLUSIONS
  We propose a new volumetric threshold of 20 cm(3) as most accurate for predicting GTR in the EEA era. CC measurement is the least useful predictor. Cavernous sinus invasion remains the best predictor of incomplete resection.
authors: Department of Neurosurgery, Memorial Sloan-Kettering Cancer Center, 1275 York Ave, New York, NY, 10065, USA. mchohan@salud.unm.edu.|Department of Neurosurgery, University of New Mexico, Albuquerque, NM, USA. mchohan@salud.unm.edu.
authors: Muhammad Omar
authors: MO
authors: Chohan
authors: Joan and Sanford I. Weill Medical College of Cornell University, New York, NY, USA.
authors: Ariana M
authors: AM
authors: Levin
authors: Joan and Sanford I. Weill Medical College of Cornell University, New York, NY, USA.
authors: Ranjodh
authors: R
authors: Singh
authors: Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY, USA.
authors: Zhiping
authors: Z
authors: Zhou
authors: Department of Neuroradiology, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY, USA.
authors: Carlos L
authors: CL
authors: Green
authors: Department of Neuroradiology, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY, USA.
authors: Jacob J
authors: JJ
authors: Kazam
authors: Department of Neuroradiology, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY, USA.
authors: Apostolos J
authors: AJ
authors: Tsiouris
authors: Department of Otolaryngology-Head and Neck Surgery, New York Presbyterian Hospital, New York, NY, USA.
authors: Vijay K
authors: VK
authors: Anand
authors: Department of Otolaryngology-Head and Neck Surgery, New York Presbyterian Hospital, New York, NY, USA.|Department of Neurological Surgery and Neuroscience, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY, USA.
authors: Theodore H
authors: TH
authors: Schwartz
mesh_terms: D000236:Adenoma / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D000368:Aged; D002426:Cavernous Sinus / Q000000981:diagnostic imaging; D016208:Databases, Factual; D005260:Female; D006801:Humans; D007016:Hypophysectomy; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009361:Neoplasm Invasiveness; D018365:Neoplasm, Residual; D044583:Neuroendoscopy; D010911:Pituitary Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D012189:Retrospective Studies; D013100:Sphenoid Bone; D016896:Treatment Outcome; D047368:Tumor Burden
keywords: Endoscopic; Giant pituitary adenoma; Knosp grade; Transsphenoidal surgery; Tumor volume