title: Correlation between Semi-Quantitative (18)F-FDG PET/CT Parameters and Ki-67 Expression in Small Cell Lung Cancer.
abstract: OBJECTIVE
  The aim of this study was to evaluate the relationship between semiquantitative parameters on (18)F-FDG PET/CT including maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) and the expression level of Ki-67 in small-cell lung cancer (SCLC).
  
  
  METHODS
  Ninety-four consecutive patients with SCLC were enrolled in this study. They underwent (18)F-FDG PET/CT for initial evaluation of SCLC, and we measured SUVmax, avgSUVmean, MTVsum, and TLGtotal on (18)F-FDG PET/CT images. The protein expression of Ki-67 was examined by immunohistochemical staining.
  
  
  RESULTS
  Significant correlations were found between the MTVsum and Ki-67 labeling index (r = 0.254, p = 0.014) and the TLGtotal and Ki-67 labeling index (r = 0.239, p = 0.020). No correlation was found between the SUVmax and Ki-67 labeling index (r = 0.116, p = 0.264) and the avgSUVmean and Ki-67 labeling index (r = 0.031, p = 0.770). Dividing the Ki-67 expression level into three categories, it was suggested that increasing Ki-67 expression level caused a stepwise increase in the MTVsum and TLGtotal. (p = 0.028 and 0.039, respectively), but not the SUVmax and avgSUVmean (p = 0.526 and 0.729, respectively).
  
  
  CONCLUSIONS
  In conclusion, the volume-based parameters of (18)F-FDG PET/CT correlate with immunohistochemical staining of Ki-67 in SCLC. Measurement of the MTVsum and TLGtotal by (18)F-FDG PET/CT might be a simple, noninvasive, and useful method to determine the proliferative potential of cancer cells.
authors.affiliation: Department of Nuclear Medicine, Korea University Guro Hospital, Seoul, South Korea.
authors.forename: Soyeon
authors.initials: S
authors.lastname: Park
authors.affiliation: Department of Nuclear Medicine, Korea University Guro Hospital, Seoul, South Korea.
authors.forename: Eunsub
authors.initials: E
authors.lastname: Lee
authors.affiliation: Department of Nuclear Medicine, Korea University Anam Hospital, #73, Inchon-ro, Seongbuk-gu, Seoul, 136-705 South Korea.
authors.forename: Seunghong
authors.initials: S
authors.lastname: Rhee
authors.affiliation: Department of Nuclear Medicine, Korea University Anam Hospital, #73, Inchon-ro, Seongbuk-gu, Seoul, 136-705 South Korea.
authors.forename: Jaehyuk
authors.initials: J
authors.lastname: Cho
authors.affiliation: Department of Nuclear Medicine, Korea University Anam Hospital, #73, Inchon-ro, Seongbuk-gu, Seoul, 136-705 South Korea.
authors.forename: Sunju
authors.initials: S
authors.lastname: Choi
authors.affiliation: Department of Nuclear Medicine, G Sam Hospital, Gunpo, South Korea.
authors.forename: Sinae
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Nuclear Medicine, Korea University Guro Hospital, Seoul, South Korea.
authors.forename: Jae Seon
authors.initials: JS
authors.lastname: Eo
authors.affiliation: Department of Nuclear Medicine, Korea University Anam Hospital, #73, Inchon-ro, Seongbuk-gu, Seoul, 136-705 South Korea ; Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea.
authors.forename: Kisoo
authors.initials: K
authors.lastname: Pahk
authors.affiliation: Department of Nuclear Medicine, Korea University Anam Hospital, #73, Inchon-ro, Seongbuk-gu, Seoul, 136-705 South Korea.
authors.forename: Jae Gol
authors.initials: JG
authors.lastname: Choe
authors.affiliation: Department of Nuclear Medicine, Korea University Anam Hospital, #73, Inchon-ro, Seongbuk-gu, Seoul, 136-705 South Korea.
authors.forename: Sungeun
authors.initials: S
authors.lastname: Kim
keywords: 18F-FDG PET/CT; Ki-67; Metabolic tumor volume; Small-cell lung carcinoma