title: The Impact That Number of Analyzed Metastatic Breast Cancer Lesions Has on Response Assessment by 18F-FDG PET/CT Using PERCIST.
abstract: The PET Response Criteria in Solid Tumors (PERCIST) are not specific regarding the number of lesions that should be analyzed per patient. This study evaluated how the number of analyzed lesions affects response assessment in metastatic breast cancer.
  
  
  
  In 60 patients, response was assessed by the change in SUVpeak, normalized to lean body mass, of the most (18)F-FDG-avid lesion (PERCIST 1) and by the change in the sum of normalized SUVpeak for up to 5 lesions (PERCIST 5). The correlation between response by PERCIST and progression-free and disease-specific survival was evaluated.
  
  
  
  In responders and nonresponders, the respective progression-free survival at 2 y was 37.26% and 6.43% for PERCIST 1 (P < 0.0001) and 33.65% and 7.14% for PERCIST 5 (P < 0.0001) and the respective disease-specific survival at 4 y was 58.96% and 25.44% for PERCIST 1 (P < 0.012) and 59.12% vs 20.01% for PERCIST 5 (P < 0.002).
  
  
  
  The number of analyzed lesions does not appear to have a major impact on the prognostic value of response assessment with (18)F-FDG PET/CT in metastatic breast cancer.
authors.affiliation: Molecular Imaging and Therapy Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York Division of Molecular and Gender Imaging, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.
authors.forename: Katja
authors.initials: K
authors.lastname: Pinker
authors.affiliation: Molecular Imaging and Therapy Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Christopher C
authors.initials: CC
authors.lastname: Riedl
authors.affiliation: Molecular Imaging and Therapy Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Leonard
authors.initials: L
authors.lastname: Ong
authors.affiliation: Breast Imaging Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Maxine
authors.initials: M
authors.lastname: Jochelson
authors.affiliation: Molecular Imaging and Therapy Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Gary A
authors.initials: GA
authors.lastname: Ulaner
authors.affiliation: Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Heather
authors.initials: H
authors.lastname: McArthur
authors.affiliation: Breast Medicine Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, and Weill Cornell Medical College, New York, New York; and.
authors.forename: Maura
authors.initials: M
authors.lastname: Dickler
authors.affiliation: Epidemiology and Biostatistics/Biostatistics, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Mithad
authors.initials: M
authors.lastname: Gönen
authors.affiliation: Molecular Imaging and Therapy Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York weberw@mskcc.org.
authors.forename: Wolfgang A
authors.initials: WA
authors.lastname: Weber
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001823:Body Composition; D001943:Breast Neoplasms / Q000000981:diagnostic imaging*; D018572:Disease-Free Survival; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000000981:diagnostic imaging; D000072078:Positron Emission Tomography Computed Tomography / Q000379:methods* / Q000706:statistics & numerical data; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D016896:Treatment Outcome
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: 18F-FDG; PERCIST; PET; breast cancer; prediction; treatment response