title: Tumour volume changes assessed with high-quality KVCT in lung cancer patients undergoing concurrent chemoradiotherapy.
abstract: OBJECTIVE
  We evaluated tumour volume changes in patients with lung cancer undergoing concurrent chemoradiotherapy using image-guided radiotherapy (RT).
  
  
  METHODS
  The kilovoltage image was obtained using CT on rail at every five fractions. The gross tumour volumes (GTVs), including the primary tumour and lymph nodes (LNs), were contoured to analyse the time and degree of tumour regression.
  
  
  RESULTS
  46 patients [32, non-small-cell lung cancer (NSCLC), and 14, small-cell lung cancer (SCLC)] were included in this study. In total, 281 CT scans and 82 sites of GTVs were evaluated. Significant volume changes occurred in both the NSCLC and SCLC groups (p < 0.001 and 0.002), and the average GTV change compared with baseline was 49.85 ± 3.65 [standard error (SE)]% and 65.95 ± 4.60 (SE)% for the NSCLC and SCLC groups, respectively. A significant difference in the degree of volume reduction between the primary tumour and LNs was observed in only the NSCLC group (p < 0.0001) but not in the SCLC group (p = 0.735). The greatest volume regression compared with the volume before the five fractions occurred between the 15 and 20 fractions in the NSCLC group and between the 5 and 10 fractions in the SCLC group.
  
  
  CONCLUSIONS
  Both primary tumour and LNs were well defined using CT on rail. Significant volume changes occurred during RT, and there was a difference in volume reduction between the NSCLC and SCLC groups, regarding the degree and timing of the tumour reduction in the primary tumour and LNs.
  
  
  CONCLUSIONS
  NSCLC and SCLC groups showed differences in the degree and timing of volume reduction. The primary tumour and LNs in NSCLC regressed differently.
authors.affiliation: 1 Department of Radiation Oncology, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: Y H
authors.initials: YH
authors.lastname: Lee
authors.affiliation: 1 Department of Radiation Oncology, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: Y S
authors.initials: YS
authors.lastname: Kim
authors.affiliation: 1 Department of Radiation Oncology, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: H C
authors.initials: HC
authors.lastname: Lee
authors.affiliation: 1 Department of Radiation Oncology, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: S W
authors.initials: SW
authors.lastname: Lee
authors.affiliation: 1 Department of Radiation Oncology, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: Y N
authors.initials: YN
authors.lastname: Kang
authors.affiliation: 2 Department of Medical Oncology, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: J H
authors.initials: JH
authors.lastname: Kang
authors.affiliation: 2 Department of Medical Oncology, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: S H
authors.initials: SH
authors.lastname: Hong
authors.affiliation: 3 Department of Internal Medicine, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: Y K
authors.initials: YK
authors.lastname: Kim
authors.affiliation: 3 Department of Internal Medicine, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: S J
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: 4 Department of Radiology, Seoul St Mary's Hospital, Seoul, College of Medicine, The Catholic University of Korea, Republic of Korea.
authors.forename: M I
authors.initials: MI
authors.lastname: Ahn
authors.affiliation: 4 Department of Radiology, Seoul St Mary's Hospital, Seoul, College of Medicine, The Catholic University of Korea, Republic of Korea.
authors.forename: D H
authors.initials: DH
authors.lastname: Han
authors.affiliation: 5 Department of Nuclear Medicine, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: I R
authors.initials: IR
authors.lastname: Yoo
authors.affiliation: 6 Department of Thoracic Surgery, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: J G
authors.initials: JG
authors.lastname: Park
authors.affiliation: 6 Department of Thoracic Surgery, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: S W
authors.initials: SW
authors.lastname: Sung
authors.affiliation: 7 Department of Pathology, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: K Y
authors.initials: KY
authors.lastname: Lee
mesh_terms: D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging / Q000473:pathology* / Q000628:therapy; D059248:Chemoradiotherapy / Q000379:methods; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D061089:Radiotherapy, Image-Guided / Q000379:methods; D055752:Small Cell Lung Carcinoma / Q000000981:diagnostic imaging / Q000473:pathology* / Q000628:therapy; D014057:Tomography, X-Ray Computed / Q000379:methods; D047368:Tumor Burden