title: Assessment of response to endocrine therapy using FDG PET/CT in metastatic breast cancer: a pilot study.
abstract: OBJECTIVE
  The purpose of this pilot study was to assess whether outcome in metastatic or recurrent breast cancer patients is related to metabolic response to endocrine therapy determined by (18)F-FDG PET/CT.
  
  
  METHODS
  The study group comprised 22 patients with breast cancer (age 58 ± 11 years, mean ± SD) who were scheduled to receive endocrine therapy. They were systematically assessed by PET/CT at baseline and after a mean of 10 ± 4 weeks for evaluation of response after induction. All patients demonstrated FDG-avid lesions on the baseline PET/CT scan. The metabolic response was assessed according to EORTC criteria and based on the mean difference in SUV(max) between the two PET/CT scans, and the patients were classified into four groups: complete or partial metabolic response, or stable or progressive metabolic disease (CMR, PMR, SMD and PMD, respectively). All patients were followed in our institution.
  
  
  RESULTS
  Metastatic sites were localized in bone (n = 15), lymph nodes (n = 11), chest wall (n = 3), breast (n = 5), lung (n = 3), soft tissue (n = 1) and liver (n = 1). PMR was observed in 11 patients (50%), SMD in 5 (23%) and PMD in 6 (27%). The median progression-free survival (PFS) times were 20, 27 and 6 months in the PMR, SMD and PMD groups, respectively. PFS in the SMD group differed from that in the PMR and SMD groups (p < 0.0001).
  
  
  CONCLUSIONS
  Metabolic response assessed by FDG PET/CT imaging in patients with metastatic breast cancer treated with endocrine therapy is predictive of the patients' PFS.
authors.affiliation: Service de Médecine nucléaire, Institut Curie, Hôpital René Huguenin, Saint-Cloud, France. nina.jehanno@gmail.com
authors.forename: Nina
authors.initials: N
authors.lastname: Mortazavi-Jehanno
authors.forename: Anne-Laure
authors.initials: AL
authors.lastname: Giraudet
authors.forename: Laurence
authors.initials: L
authors.lastname: Champion
authors.forename: Florence
authors.initials: F
authors.lastname: Lerebours
authors.forename: Elise
authors.initials: E
authors.lastname: Le Stanc
authors.forename: Veronique
authors.initials: V
authors.lastname: Edeline
authors.forename: Olivier
authors.initials: O
authors.lastname: Madar
authors.forename: Dominique
authors.initials: D
authors.lastname: Bellet
authors.forename: Alain Paul
authors.initials: AP
authors.lastname: Pecking
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Alberini
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D019788:Fluorodeoxyglucose F18; D006728:Hormones / Q000627:therapeutic use*; D006801:Humans; D008875:Middle Aged; D018396:Mucin-1 / Q000097:blood; D064847:Multimodal Imaging; D009362:Neoplasm Metastasis; D010865:Pilot Projects; D049268:Positron-Emission Tomography; D012008:Recurrence; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D006728:Hormones; D018396:Mucin-1; D019788:Fluorodeoxyglucose F18