title: Prone Versus Supine Breast FDG-PET/CT for Assessing Locoregional Disease Distribution in Locally Advanced Breast Cancer.
abstract: OBJECTIVE
  Prone (18)F fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) may have advantages for breast imaging because of improved separation of deep anatomic structures. There are limited data on whether prone and supine FDG-PET/CT provide similar information regarding breast and axillary disease in the setting of locally advanced breast cancer (LABC). The purpose of this study was to compare the information on locoregional disease distribution provided by prone versus supine FDG-PET in newly diagnosed LABC.
  
  
  METHODS
  In an Institutional Review Board-approved prospective trial, 24 patients with newly diagnosed LABC underwent both supine and prone FDG-PET/CT at the same scanning session. Three readers performed an independent review of all scans and categorized the locoregional disease distribution as breast only (BO)-unifocal, BO-multifocal, BO-multicentric, or breast + axillary involvement. For breast + axillary disease, the readers also assessed the number of involved axillary lymph nodes. Interobserver discrepancies were resolved at a consensus reading session.
  
  
  RESULTS
  Two scanning sessions were excluded because the prone scan had omitted part of the axilla from the field of view. In the remaining 22 patients, the consensus categorization of anatomic disease distribution was concordant between prone and supine scanning in 21 patients (linear kappa 0.91, 95% confidence interval [0.79-1]). In the 16 patients with breast + axillary disease, equal numbers of involved lymph nodes were identified on prone and supine scanning in 12 patients, whereas in the remaining four patients, prone scanning resulted in a higher number of visualized lymph nodes.
  
  
  CONCLUSIONS
  Prone and supine FDG-PET/CT provided statistically identical information on locoregional disease distribution in LABC. However, prone scanning may perform better than supine for assessing the number of involved lymph nodes. Prone FDG-PET/CT may be useful in future clinical and research efforts, including hybrid PET-magnetic resonance imaging (MRI) applications.
authors: Department of Radiology and Radiological Sciences, Vanderbilt University, 1161 21st Avenue S, CCC-1121 MCN, Nashville, TN 37232-2675. Electronic address: richard.abramson@vanderbilt.edu.
authors: Richard G
authors: RG
authors: Abramson
authors: Department of Radiology and Radiological Sciences, Vanderbilt University, 1161 21st Avenue S, CCC-1121 MCN, Nashville, TN 37232-2675.
authors: Katrina F
authors: KF
authors: Lambert
authors: Department of Radiology and Radiological Sciences, Vanderbilt University, 1161 21st Avenue S, CCC-1121 MCN, Nashville, TN 37232-2675.
authors: Laurie B
authors: LB
authors: Jones-Jackson
authors: Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee.
authors: Lori R
authors: LR
authors: Arlinghaus
authors: Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee.
authors: Jason
authors: J
authors: Williams
authors: Vanderbilt-Ingram Cancer Center, Nashville, Tennessee.
authors: Vandana G
authors: VG
authors: Abramson
authors: Department of Radiation Oncology, Vanderbilt University Medical Center, Nashville, Tennessee.
authors: A Bapsi
authors: AB
authors: Chakravarthy
authors: Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee.
authors: Thomas E
authors: TE
authors: Yankeelov
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000473:pathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D009361:Neoplasm Invasiveness; D056888:Patient Positioning / Q000379:methods*; D049268:Positron-Emission Tomography / Q000379:methods*; D016684:Prone Position; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016683:Supine Position; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: Neoadjuvant chemotherapy; nodal disease burden; radiation planning; risk stratification