title: Evaluation of sorafenib treatment in metastatic renal cell carcinoma with 2-fluoro-2-deoxyglucose positron emission tomography and computed tomography.
abstract: OBJECTIVE
  New potent tyrosine kinase inhibitors such as sorafenib are the most effective treatment for metastatic renal cell carcinoma (MRCC) today. In this study, we used [18F]-2-fluoro-2-deoxyglucose (FDG) with positron emission tomography (PET) combined with computed tomography (CT) to evaluate early effects of sorafenib in patients with MRCC.
  
  
  METHODS
  Ten patients, eight males and two females, with a mean age of 61 years (49-72 years), with MRCC were enrolled. A total of 52 lesions, two to nine lesions/patient, out of which 39 were soft lesions, were evaluated. The [18F]FDG-PET/CT was performed before treatment and after 1-2 months. A region of interest (ROI) was identified including the lesions where the glucose uptake was measured, calculating the average value within the ROI and using the cerebellum as the reference. The same ROI was measured in the subsequent FDG-PET. The sum of the diameters was measured in CT according to the Response Evaluation Criteria in Solid Tumors (RECIST). Sorafenib was given 400 mg twice daily orally.
  
  
  RESULTS
  After 1-2 months, the mean glucose uptake in all lesions decreased to 75% (32-105%) of initial values of ROI as measured by FDG-PET. The mean glucose uptake in soft lesions decreased to 71% (32-108%) and in skeletal lesions to 82% (53-101%). The sum of the diameters measured by CT decreased to 80% (57-94%) of the initial value in soft lesions according to the RECIST.
  
  
  CONCLUSIONS
  An early decrease in the mean glucose uptake was found in both soft and skeletal lesions after treatment with sorafenib. FDG-PET thus seems to be advantageous, compared with RECIST evaluation, which is limited to soft lesions.
authors.affiliation: Department of Urology, Sahlgrenska University Hospital, Göteborg S-41345, Sweden. sven.lundstam@vgregion.se
authors.forename: David
authors.initials: D
authors.lastname: Lyrdal
authors.forename: Marianne
authors.initials: M
authors.lastname: Boijsen
authors.forename: Madis
authors.initials: M
authors.lastname: Suurküla
authors.forename: Sven
authors.initials: S
authors.lastname: Lundstam
authors.forename: Ulrika
authors.initials: U
authors.lastname: Stierner
mesh_terms: D000368:Aged; D001557:Benzenesulfonates / Q000627:therapeutic use*; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009536:Niacinamide / Q000031:analogs & derivatives; D010671:Phenylurea Compounds; D049268:Positron-Emission Tomography; D011725:Pyridines / Q000627:therapeutic use*; D000077157:Sorafenib; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D001557:Benzenesulfonates; D010671:Phenylurea Compounds; D011725:Pyridines; D019788:Fluorodeoxyglucose F18; D009536:Niacinamide; D000077157:Sorafenib