title: 18F-FDG uptake as a biologic prognostic factor for recurrence in patients with surgically resected non-small cell lung cancer.
abstract: Among patients with resected non-small cell lung cancer (NSCLC), approximately 50% present with a recurrent tumor. The clinical or pathologic TNM staging does not always provide a satisfactory explanation for differences in relapse and survival. Thus, it is of major importance to be able to predict these relapses and to prevent them with an active chemotherapy or radiotherapy program (or both). 18F-FDG uptake on PET could be of prognostic significance in patients with resected NSCLC. The goal of this study was to determine whether the level of metabolic activity observed with 18F-FDG uptake correlates with the probability of postoperative recurrence in patients with NSCLC.
  
  
  METHODS
  Fifty-seven patients with NSCLC were examined with 18F-FDG PET. For semiquantitative analysis, standardized uptake values (SUVs) were calculated. Patients were classified into high-SUV (> 5.0) and low-SUV (< or = 5.0) groups. All patients underwent thoracotomy within 4 wk after the 18F-FDG PET study. Tumor 18F-FDG uptake (SUV), pathologic stage, and lesion size were analyzed for their possible association with disease-free survival.
  
  
  RESULTS
  Forty-six patients had pathologic stage I NSCLC and 11 had pathologic stage II or stage III NSCLC. In a univariate analysis, patients with an SUV of < or = 5 had a much better disease-free survival than did patients with an SUV of > 5 (P < 0.0001). In patients with pathologic stage I and stage IA NSCLC, the SUV was also correlated with disease-free survival (P < 0.0001 and P = 0.0012, respectively). Patients with pathologic stage I disease had an expected 5-y disease-free survival rate of 88% if the SUV was < or = 5 and a survival rate of < or = 17% if the SUV was > 5. A multivariate Cox analysis identified the SUV as the most significant independent factor for disease-free survival.
  
  
  CONCLUSIONS
  We conclude that the 18F-FDG uptake in primary NSCLC determined by PET has a significant independent postoperative prognostic value for recurrence, especially in patients with pathologic stage I NSCLC. 18F-FDG uptake was superior to pathologic stage in predicting relapse of patients with NSCLC.
authors.affiliation: Department of Radiology, Kanazawa Medical University, Ishikawa, Japan. h550208@kanazawa-med.ac.jp
authors.forename: Kotaro
authors.initials: K
authors.lastname: Higashi
authors.forename: Yoshimichi
authors.initials: Y
authors.lastname: Ueda
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Arisaka
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Sakuma
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Nambu
authors.forename: Manabu
authors.initials: M
authors.lastname: Oguchi
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Seki
authors.forename: Suzuka
authors.initials: S
authors.lastname: Taki
authors.forename: Hisao
authors.initials: H
authors.lastname: Tonami
authors.forename: Itaru
authors.initials: I
authors.lastname: Yamamoto
mesh_terms: D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000601:surgery; D018572:Disease-Free Survival; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008168:Lung / Q000473:pathology; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology*; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D019275:Radiopharmaceuticals; D016019:Survival Analysis; D014055:Tomography, Emission-Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18