title: Solid tumor size on high-resolution computed tomography and maximum standardized uptake on positron emission tomography for new clinical T descriptors with T1 lung adenocarcinoma.
abstract: BACKGROUND
  To better describe clinical T descriptors using solid tumor size (the maximum dimension of the solid component of the tumor) on high-resolution computed tomography (HRCT) and maximum standardized uptake value (SUVmax) on F-18-fluorodeoxyglucose positron emission tomography/CT (FDG-PET/CT).
  
  
  METHODS
  We examined 610 consecutive patients with clinical stage IA lung adenocarcinoma who underwent complete resection. Recurrence-free survival (RFS) was assessed on the basis of whole tumor size (maximum dimension of the tumor), solid tumor size, or a combination of solid tumor size and SUVmax.
  
  
  RESULTS
  RFS based on whole tumor size was not significantly different between patients with tumors measuring ≤2 cm and 2-3 cm (P = 0.089), whereas RFS based on solid tumor size was significantly different (P < 0.0001). We divided patients into four groups on the basis of solid tumor size and SUVmax: group 1: solid tumor size ≤2 cm, SUVmax ≤1.8; group 2: solid tumor size ≤2 cm, SUVmax >1.8; group 3: solid tumor size 2-3 cm, SUVmax ≤3.6; and group 4: solid tumor size 2-3 cm, SUVmax >3.6. Groups 2 and 3 were combined because they showed similar RFS each other. RFS was significantly different among these groups: group 1 versus groups 2 + 3, P < 0.0001; groups 2 + 3 versus group 4, P = 0.019.
  
  
  CONCLUSIONS
  Both solid tumor size on HRCT and SUVmax on FDG-PET/CT reflect prognosis well in patients with clinical stage IA lung adenocarcinoma and may support new clinical T descriptors.
authors.affiliation: Department of Surgical Oncology, Hiroshima University, Hiroshima, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Tsutani
authors.forename: Y
authors.initials: Y
authors.lastname: Miyata
authors.forename: H
authors.initials: H
authors.lastname: Nakayama
authors.forename: S
authors.initials: S
authors.lastname: Okumura
authors.forename: S
authors.initials: S
authors.lastname: Adachi
authors.forename: M
authors.initials: M
authors.lastname: Yoshimura
authors.forename: M
authors.initials: M
authors.lastname: Okada
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging* / Q000601:surgery; D000077192:Adenocarcinoma of Lung; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000000981:diagnostic imaging; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography; D014057:Tomography, X-Ray Computed
keywords: T descriptor; TNM classification; lung adenocarcinoma; positron emission tomography