title: Early assessment by FDG-PET/CT of patients with advanced renal cell carcinoma treated with tyrosine kinase inhibitors is predictive of disease course.
abstract: BACKGROUND
  We reported previously that (18)F-2-fluoro-2-deoxyglucose positron emission tomography/ computed tomography (FDG PET/CT) had potential for evaluating early response to treatment by tyrosine kinase inhibitors (TKIs) in advanced renal cell carcinoma (RCC). This time we investigated the relation of the early assessment by FDG PET/CT to long-term prognosis with an expanded number of patients and period of observation.
  
  
  METHODS
  Patients for whom TKI treatment for advanced RCC was planned were enrolled. FDG PET/CT was performed before TKI treatment and after one month of TKI treatment. The relations of the FDGPET/CT assessment to progression free survival (PFS) and overall survival (OS) were investigated.
  
  
  RESULTS
  Thirty-five patients were enrolled (sunitinib 19 cases, sorafenib 16 cases). The patients with RCC showing high SUVmax in pretreatment FDG PET/CT demonstrated short PFS (P =0.024, hazard ratio 1.137, 95% CI 1.017-1.271) and short OS (P =0.004, hazard ratio 1.210 95% CI 1.062-1.379). Thirty patients (sunitinib 16 cases, sorafenib 14 cases) were evaluated again after 1 month. The PFS of the patients whose SUVmax decreased<20% was shorter than that of the patients whose SUVmax decreased<20% (P = 0.027, hazard ratio 3.043, 95% CI 1.134-8.167). The PFS of patients whose tumor diameter sum increased was shorter than that of the patient with tumors whose diameter sum did not (P =0.006, hazard ratio 4.555, 95% CI 1.543-13.448). The patients were classified into three response groups: good responder (diameter sum did not increase, and SUVmax decreased ≥ 20%), intermediate responder (diameter sum did not increase, and SUVmax decreased<20%), and poor responder (diameter sum increased, or one or more new lesions appeared). The median PFS of good, intermediate, and poor responders were 458 ± 146 days, 131 ± 9 days, and 88 ± 26 days (good vs. intermediate P = 0.0366, intermediate vs. poor P = 0.0097, log-rank test). Additionally the mean OSs were 999 ± 70 days, 469 ± 34 days, and 374 ± 125 days, respectively (good vs. intermediate P = 0.0385, intermediate vs. poor P = 0.0305, log-rank test).
  
  
  CONCLUSIONS
  The evaluation of RCC response to TKI by tumor size and FDG uptake using FDG PET/CT after 1 month can predict PFS and OS.
authors.affiliation: Department of Urology, Yokohama City University Graduate School of Medicine, 3-9 Fukuura kanazawaku, Yokohama, 236-0004, Japan.
authors.forename: Daiki
authors.initials: D
authors.lastname: Ueno
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yao
authors.forename: Ukihide
authors.initials: U
authors.lastname: Tateishi
authors.forename: Ryogo
authors.initials: R
authors.lastname: Minamimoto
authors.forename: Kazuhide
authors.initials: K
authors.lastname: Makiyama
authors.forename: Narihiko
authors.initials: N
authors.lastname: Hayashi
authors.forename: Futoshi
authors.initials: F
authors.lastname: Sano
authors.forename: Takayuki
authors.initials: T
authors.lastname: Murakami
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kishida
authors.forename: Takeshi
authors.initials: T
authors.lastname: Miura
authors.forename: Kazuki
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Sumio
authors.initials: S
authors.lastname: Noguchi
authors.forename: Ichiro
authors.initials: I
authors.lastname: Ikeda
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Ohgo
authors.forename: Tomio
authors.initials: T
authors.lastname: Inoue
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Kubota
authors.forename: Noboru
authors.initials: N
authors.lastname: Nakaigawa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001557:Benzenesulfonates / Q000627:therapeutic use; D002292:Carcinoma, Renal Cell / Q000175:diagnosis* / Q000188:drug therapy* / Q000401:mortality; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007211:Indoles / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D009367:Neoplasm Staging; D009536:Niacinamide / Q000031:analogs & derivatives; D010671:Phenylurea Compounds; D049268:Positron-Emission Tomography; D011379:Prognosis; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use*; D011725:Pyridines / Q000627:therapeutic use; D011758:Pyrroles / Q000627:therapeutic use; D000077157:Sorafenib; D000077210:Sunitinib; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D001557:Benzenesulfonates; D007211:Indoles; D010671:Phenylurea Compounds; D047428:Protein Kinase Inhibitors; D011725:Pyridines; D011758:Pyrroles; D019788:Fluorodeoxyglucose F18; D009536:Niacinamide; D000077157:Sorafenib; D000077210:Sunitinib