title: Tumor response in patients with advanced non-small cell lung cancer: perfusion CT evaluation of chemotherapy and radiation therapy.
abstract: OBJECTIVE
  The objectives of this study were to prospectively evaluate changes in tumor perfusion after chemoradiation therapy and to investigate the feasibility of perfusion CT for prediction of early tumor response and prognosis of non-small cell lung cancer.
  
  
  METHODS
  Perfusion CT was performed on an MDCT scanner with 50 mL of iodinated contrast material injected at 4 mL/s. The quality of each functional map was rated from 0 to 3 for 123 patients with confirmed lung cancer. A subset of images was independently reviewed by two radiologists to measure interobserver and intraobserver variability. Perfusion parameters and tumor response were assessed for 35 patients with non-small cell lung cancer who underwent chemoradiation therapy. Progression-free survival and overall survival were analyzed for 22 patients who underwent repeated perfusion CT after therapy.
  
  
  RESULTS
  Image quality was graded 2 (moderate) or 3 (good) in 68.2% of cases. High interobserver and intraobserver correlations of perfusion parameters were found on qualified images. The patients who responded to chemoradiation therapy had significantly greater blood flow (p = 0.023) than patients who did not respond. The median progression-free survival period of the patients with an increased permeability-surface area product was 4.7 months, significantly lower than the median progression-free survival period of 19.0 months among patients with a decreased permeability-surface area product (p < 0.001). The median overall survival period was 10.6 months for the group with an increased permeability-surface area product, significantly lower than the 19.3 months for the group with a decreased permeability-surface area product (p = 0.004).
  
  
  CONCLUSIONS
  Non-small cell lung cancer with higher perfusion is more sensitive to chemoradiation therapy than that with lower perfusion. After chemoradiation therapy, findings at perfusion CT are a significant predictor of early tumor response and overall survival among patients with non-small cell lung cancer.
authors.affiliation: Department of Diagnostic Radiology, Cancer Hospital and Institute, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100021, China.
authors.forename: Jianwei
authors.initials: J
authors.lastname: Wang
authors.forename: Ning
authors.initials: N
authors.lastname: Wu
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Cham
authors.forename: Ying
authors.initials: Y
authors.lastname: Song
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use*; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000628:therapy*; D003131:Combined Modality Therapy; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000628:therapy*; D055420:Perfusion Imaging / Q000379:methods*; D011379:Prognosis; D020266:Radiotherapy, Conformal; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents