title: 18F-FDG PET/CT for early prediction of response to neoadjuvant chemotherapy in breast cancer.
abstract: OBJECTIVE
  The aim of this study was to prospectively evaluate 18F-FDG PET/CT in predicting response to neoadjuvant chemotherapy in large primary breast cancer.
  
  
  METHODS
  Fifty consecutive patients underwent PET/CT at baseline and after the second cycle. Baseline MRI was performed to establish tumour size. All findings were confirmed by histopathological analysis. Changes in maximum standardized uptake value (SUV(max)) between baseline study and after two cycles of neoadjuvant chemotherapy (epirubicin + cyclophosphamide + taxanes) were compared using response evaluation criteria in solid tumours (RECIST) criteria and the Miller and Payne (M&P) scale.
  
  
  RESULTS
  The mean tumour size was 4.3 +/- 1.4 cm. Forty patients were considered responders and ten as non-responders. SUV(max) changes in patients with good prognosis (M&P grades 4-5) were higher than in patients with bad prognosis (M&P grades 1-3) (p = 0.025). SUV(max) changes between responders and non-responders following RECIST criteria were also statistically significant (p = 0.0028). A cut-off DeltaSUV value of 40% differentiates both groups, with a sensitivity of 77% and a specificity of 80%.
  
  
  CONCLUSIONS
  18F-FDG PET/CT can predict response to neoadjuvant chemotherapy at an early stage.
authors.affiliation: Nuclear Medicine Department, Hospital Clínic de Barcelona, Villarroel, 170, 08036, Barcelona, Spain. joanduch@gmail.com
authors.forename: Joan
authors.initials: J
authors.lastname: Duch
authors.forename: David
authors.initials: D
authors.lastname: Fuster
authors.forename: Montserrat
authors.initials: M
authors.lastname: Muñoz
authors.forename: Pedro Luís
authors.initials: PL
authors.lastname: Fernández
authors.forename: Pilar
authors.initials: P
authors.lastname: Paredes
authors.forename: Montserrat
authors.initials: M
authors.lastname: Fontanillas
authors.forename: Flavia
authors.initials: F
authors.lastname: Guzmán
authors.forename: Sebastià
authors.initials: S
authors.lastname: Rubí
authors.forename: Francisco Juan
authors.initials: FJ
authors.lastname: Lomeña
authors.forename: Francesca
authors.initials: F
authors.lastname: Pons