title: FDG PET/CT as a prognostic biomarker in the era of molecular-targeting therapies: max SUVmax predicts survival of patients with advanced renal cell carcinoma.
abstract: BACKGROUND
  Various molecular-targeting therapies have become available for the treatment of advanced renal cell carcinoma (RCC). Accurate prognostication is desirable for choosing the appropriate treatment for individual patients. (18)F-2-fluoro-2-deoxyglucose positron-emission tomography/computed tomography (FDG PET/CT) is a non-invasive tool for evaluating glucose accumulation, which can be an index of biological characteristics of cancer. We prospectively evaluated FDG PET/CT as a prognostic indicator in patients with advanced RCC.
  
  
  METHODS
  A total of 101 patients slated for different systematic therapies for advanced RCC were enrolled between 2008 and 2014. A total of 61 patients had recurrent RCC (58 metastatic and 3 regional) and 40 patients had stage IV RCC (36 metastatic and 4 locoregional). Sixteen patients had not undergone nephrectomy. Pre-treatment FDG PET/CT was performed, and the max SUVmax (the highest SUV measurement in each patient) was recorded. The max SUVmax was compared with different clinical risk factors as prognostic indicators. The median observation period was 18 months (range 1-70 months).
  
  
  RESULTS
  The max SUVmax of the 101 subjects ranged from undetectable to 23.0 (median 6.9). Patients with high max SUVmax had a poor prognosis. Multivariate analysis with standard risk factors revealed that max SUVmax was an independent predictor of survival (p < 0.001; hazard ratio 1.265; 95% confidence interval 1.159-1.380). A cutoff of 8.8 for max SUVmax advocated in our previous report was highly significant (p < 0.0001). When we subclassified the max SUVmax values, the median overall survival of subjects with max SUVmax < 7.0 was 41.9 months. That of subjects with max SUVmax between 7.0 and 12.0 was 20.6 months. That of subjects with max SUVmax ≥ 12.0 was 4.2 months. The differences were statistically significant.
  
  
  CONCLUSIONS
  Pretreatment max SUVmax assessed by FDG PET/CT is a useful prognostic marker for patients with advanced RCC, providing helpful information for clinical decision making.
authors: Department of Urology, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Kanazawa, Yokohama, 236-0004, Japan. nakaigan@med.yokohama-cu.ac.jp.
authors: Noboru
authors: N
authors: Nakaigawa
authors: Department of Urology, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Kanazawa, Yokohama, 236-0004, Japan.
authors: Keiichi
authors: K
authors: Kondo
authors: Department of Radiology, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
authors: Ukihide
authors: U
authors: Tateishi
authors: Department of Radiology, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
authors: Ryogo
authors: R
authors: Minamimoto
authors: Department of Radiology, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
authors: Tomohiro
authors: T
authors: Kaneta
authors: Department of Urology, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Kanazawa, Yokohama, 236-0004, Japan.
authors: Kazuhiro
authors: K
authors: Namura
authors: Department of Urology, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Kanazawa, Yokohama, 236-0004, Japan.
authors: Daiki
authors: D
authors: Ueno
authors: Department of Urology, Yokosuka Kyosai Hospital, Yokosuka, Japan.
authors: Kazuki
authors: K
authors: Kobayashi
authors: Department of Urology, Kanagawa Cancer Center, Yokohama, Japan.
authors: Takeshi
authors: T
authors: Kishida
authors: Department of Urology, Yokohama Minami Kyosai Hospital, Yokohama, Japan.
authors: Ichiro
authors: I
authors: Ikeda
authors: Department of Urology, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Kanazawa, Yokohama, 236-0004, Japan.
authors: Hisashi
authors: H
authors: Hasumi
authors: Department of Urology, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Kanazawa, Yokohama, 236-0004, Japan.
authors: Kazuhide
authors: K
authors: Makiyama
authors: Department of Urology, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Kanazawa, Yokohama, 236-0004, Japan.
authors: Yoshinobu
authors: Y
authors: Kubota
authors: Department of Radiology, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
authors: Tomio
authors: T
authors: Inoue
authors: Department of Urology, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Kanazawa, Yokohama, 236-0004, Japan.
authors: Masahiro
authors: M
authors: Yao
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000627:therapeutic use; D005947:Glucose / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D058990:Molecular Targeted Therapy; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy*; D009367:Neoplasm Staging; D009392:Nephrectomy; D049268:Positron-Emission Tomography; D011379:Prognosis; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D019788:Fluorodeoxyglucose F18; D005947:Glucose