title: Pilot study of DCE-MRI to predict progression-free survival with sorafenib therapy in renal cell carcinoma.
abstract: BACKGROUND
  The investigation of angiogenesis inhibitors is of particular interest in renal cell carcinoma (RCC), in which dysregulated blood vessel formation has been correlated with shortened survival. Sorafenib is a novel RAF and VEGF receptor tyrosine kinase inhibitor. We conducted this study to (a) determine if sorafenib is anti-angiogenic, and (b) to relate anti-angiogenic effect to outcome.
  
  
  RESULTS
  Four patients achieved partial response by WHO criteria (ORR 24%). Median time to progression (TTP) was 12.9 months. K(trans) decreased significantly during treatment with sorafenib (60.3% decline, 95% CI 46.1-74.6%). The percent decline in K(trans) and change in tumor size by CT scan were significantly associated with progression-free survival (p = 0.01 and 0.05, respectively). In addition, K(trans) at baseline was also significantly associated with progress-free survival (p = 0.02).
  
  
  METHODS
  Seventeen patients with metastatic RCC underwent dynamic-contrast enhanced magnetic resonance imaging (DCE-MRI). DCE-MRI was used to calculate the gadolinium exchange constant between blood and tumor interstitial tissue, K(trans).
  
  
  CONCLUSIONS
  In patients with RCC, inhibition of tumor vascular permeability by sorafenib was associated with improved outcome. Moreover, baseline tumor vascular permeability, expected to be a poor prognosis factor, was a predictive marker of favorable response to therapy.
authors.affiliation: Abramson Cancer Center, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA. ktflaherty@aol.com
authors.forename: Keith T
authors.initials: KT
authors.lastname: Flaherty
authors.forename: Mark A
authors.initials: MA
authors.lastname: Rosen
authors.forename: Daniel F
authors.initials: DF
authors.lastname: Heitjan
authors.forename: Maryann L
authors.initials: ML
authors.lastname: Gallagher
authors.forename: Brian
authors.initials: B
authors.lastname: Schwartz
authors.forename: Mitchell D
authors.initials: MD
authors.lastname: Schnall
authors.forename: Peter J
authors.initials: PJ
authors.lastname: O'Dwyer
mesh_terms: D000328:Adult; D000368:Aged; D020533:Angiogenesis Inhibitors / Q000627:therapeutic use*; D001557:Benzenesulfonates / Q000627:therapeutic use*; D002292:Carcinoma, Renal Cell / Q000098:blood supply / Q000188:drug therapy* / Q000473:pathology; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000098:blood supply / Q000188:drug therapy* / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000188:drug therapy*; D009536:Niacinamide / Q000031:analogs & derivatives; D010671:Phenylurea Compounds; D010865:Pilot Projects; D019908:Proto-Oncogene Proteins c-raf / Q000037:antagonists & inhibitors; D011725:Pyridines / Q000627:therapeutic use*; D040262:Receptors, Vascular Endothelial Growth Factor / Q000037:antagonists & inhibitors; D000077157:Sorafenib; D016019:Survival Analysis
chemical_list: D020533:Angiogenesis Inhibitors; D001557:Benzenesulfonates; D010671:Phenylurea Compounds; D011725:Pyridines; D009536:Niacinamide; D000077157:Sorafenib; D040262:Receptors, Vascular Endothelial Growth Factor; D019908:Proto-Oncogene Proteins c-raf