title: Association between partial-volume corrected SUVmax and Oncotype DX recurrence score in early-stage, ER-positive/HER2-negative invasive breast cancer.
abstract: OBJECTIVE
  Oncotype DX, a 21-gene expression assay, provides a recurrence score (RS) which predicts prognosis and the benefit from adjuvant chemotherapy in patients with early-stage, estrogen receptor-positive (ER-positive), and human epidermal growth factor receptor 2-negative (HER2-negative) invasive breast cancer. However, Oncotype DX tests are expensive and not readily available in all institutions. The purpose of this study was to investigate whether metabolic parameters on (18)F-FDG PET/CT are associated with the Oncotype DX RS and whether (18)F-FDG PET/CT can be used to predict the Oncotype DX RS.
  
  
  METHODS
  The study group comprised 38 women with stage I/II, ER-positive/HER2-negative invasive breast cancer who underwent pretreatment (18)F-FDG PET/CT and Oncotype DX testing. On PET/CT, maximum (SUVmax) and average standardized uptake values, metabolic tumor volume, and total lesion glycolysis were measured. Partial volume-corrected SUVmax (PVC-SUVmax) determined using the recovery coefficient method was also evaluated. Oncotype DX RS (0 - 100) was categorized as low (<18), intermediate (18 - 30), or high (≥31). The associations between metabolic parameters and RS were analyzed. Multivariate logistic regression was used to identify significant independent predictors of low versus intermediate-to-high RS.
  
  
  RESULTS
  Of the 38 patients, 22 (58 %) had a low RS, 13 (34 %) had an intermediate RS, and 3 (8 %) had a high RS. In the analysis with 38 index tumors, PVC-SUVmax was higher in tumors in patients with intermediate-to-high RS than in those with low RS (5.68 vs. 4.06; P = 0.067, marginally significant). High PVC-SUVmax (≥4.96) was significantly associated with intermediate-to-high RS (odds ratio, OR, 10.556; P = 0.004) in univariate analysis. In multivariate analysis with clinicopathologic factors, PVC-SUVmax ≥4.96 (OR 8.459; P = 0.013) was a significant independent predictor of intermediate-to-high RS.
  
  
  CONCLUSIONS
  High PVC-SUVmax on (18)F-FDG PET/CT was significantly associated with an intermediate-to-high Oncotype DX RS. PVC metabolic parameters on (18)F-FDG PET/CT can be used to predict the Oncotype DX RS in patients with early-stage, ER-positive/HER2-negative breast cancer.
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Su Hyun
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Nuclear Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea.|Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, and College of Medicine or College of Pharmacy, Seoul National University, Seoul, South Korea.
authors.forename: Seunggyun
authors.initials: S
authors.lastname: Ha
authors.affiliation: Department of Nuclear Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea.|Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Hyun Joon
authors.initials: HJ
authors.lastname: An
authors.affiliation: Department of Nuclear Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea.|Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Jae Sung
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Department of Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Wonshik
authors.initials: W
authors.lastname: Han
authors.affiliation: Department of Internal Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Seock-Ah
authors.initials: SA
authors.lastname: Im
authors.affiliation: Department of Pathology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Han Suk
authors.initials: HS
authors.lastname: Ryu
authors.affiliation: Department of Radiology, Kyungpook National University Hospital, Daegu, South Korea.
authors.forename: Won Hwa
authors.initials: WH
authors.lastname: Kim
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Jung Min
authors.initials: JM
authors.lastname: Chang
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Nariya
authors.initials: N
authors.lastname: Cho
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea. moonwk@snu.ac.kr.|Cancer Research Institute, Seoul National University College of Medicine, Seoul, South Korea. moonwk@snu.ac.kr.|Radiation Medicine Research Institute, Seoul National University College of Medicine, Seoul, South Korea. moonwk@snu.ac.kr.
authors.forename: Woo Kyung
authors.initials: WK
authors.lastname: Moon
authors.affiliation: Department of Nuclear Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea. larrycheon@gmail.com.|Cancer Research Institute, Seoul National University College of Medicine, Seoul, South Korea. larrycheon@gmail.com.|Radiation Medicine Research Institute, Seoul National University College of Medicine, Seoul, South Korea. larrycheon@gmail.com.
authors.forename: Gi Jeong
authors.initials: GJ
authors.lastname: Cheon
mesh_terms: D000328:Adult; D001692:Biological Transport; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism*; D006801:Humans; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D000072078:Positron Emission Tomography Computed Tomography; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism*; D012008:Recurrence; D047368:Tumor Burden
chemical_list: D014408:Biomarkers, Tumor; D019788:Fluorodeoxyglucose F18; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen
keywords: 18F-FDG PET/CT; Breast cancer; Oncotype DX; Oncotype DX recurrence score; Partial volume correction; Recovery coefficient