title: Progression of non-small-cell lung cancer during the interval before stereotactic body radiotherapy.
abstract: OBJECTIVE
  To investigate the relationship between waiting time (WT) and disease progression in patients undergoing stereotactic body radiotherapy (SBRT) for lung adenocarcinoma (AD) or squamous cell carcinoma (SQ).
  
  
  METHODS
  201 patients with Stage I AD or SQ undergoing SBRT between January 2004 and June 2010 were analyzed. The WT was defined as the interval between diagnostic computed tomography before referral and computed tomography for treatment planning or positioning before SBRT. Tumor size was measured on the slice of the longest tumor diameter, and tumor volume was calculated from the longest diameter and the diameter perpendicular to it. Changes in tumor volume and TNM stage progression were evaluated, and volume doubling time (VDT) was estimated.
  
  
  RESULTS
  The median WT was 42 days (range, 5-323 days). There was a correlation between WT and rate of increase in volume in both AD and SQ. The median VDTs of AD and SQ were 170 and 93 days, respectively. Thirty-six tumors (23%) did not show volume increase during WTs >25 days. In 41 patients waiting for ≤4 weeks, no patient showed T stage progression, whereas in 25 of 120 (21%) patients waiting for >4 weeks, T stage progressed from T1 to T2 (p = 0.001). In 10 of 110 (9.1%) T1 ADs and 15 of 51 (29%) T1 SQs, T stage progressed (p = 0.002). N stage and M stage progressions were not observed.
  
  
  CONCLUSIONS
  Generally, a WT of ≤4 weeks seems to be acceptable. The WT seems to be more important in SQ than in AD.
authors.affiliation: Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan. taro8864@hotmail.com
authors.forename: Taro
authors.initials: T
authors.lastname: Murai
authors.forename: Yuta
authors.initials: Y
authors.lastname: Shibamoto
authors.forename: Fumiya
authors.initials: F
authors.lastname: Baba
authors.forename: Chisa
authors.initials: C
authors.lastname: Hashizume
authors.forename: Yoshimasa
authors.initials: Y
authors.lastname: Mori
authors.forename: Shiho
authors.initials: S
authors.lastname: Ayakawa
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Kawai
authors.forename: Shinya
authors.initials: S
authors.lastname: Takemoto
authors.forename: Chikao
authors.initials: C
authors.lastname: Sugie
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ogino
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D000077192:Adenocarcinoma of Lung; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D018450:Disease Progression; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods*; D056888:Patient Positioning; D011859:Radiography; D016634:Radiosurgery; D011880:Radiotherapy Planning, Computer-Assisted; D018709:Statistics, Nonparametric; D013997:Time Factors; D047368:Tumor Burden