title: Reduction in Tumor Volume by Cone Beam Computed Tomography Predicts Overall Survival in Non-Small Cell Lung Cancer Treated With Chemoradiation Therapy.
abstract: OBJECTIVE
  We sought to evaluate whether tumor response using cone beam computed tomography (CBCT) performed as part of the routine care during chemoradiation therapy (CRT) could forecast the outcome of unresectable, locally advanced, non-small cell lung cancer (NSCLC).
  
  
  METHODS
  We manually delineated primary tumor volumes (TV) of patients with NSCLC who were treated with radical CRT on days 1, 8, 15, 22, 29, 36, and 43 on CBCTs obtained as part of the standard radiation treatment course. Percentage reductions in TV were calculated and then correlated to survival and pattern of recurrence using Cox proportional hazard models. Clinical information including histologic subtype was also considered in the study of such associations.
  
  
  RESULTS
  We evaluated 38 patients with a median follow-up time of 23.4 months. The median TV reduction was 39.3% (range, 7.3%-69.3%) from day 1 (D1) to day 43 (D43) CBCTs. Overall survival was associated with TV reduction from D1 to D43 (hazard ratio [HR] 0.557, 95% CI 0.39-0.79, P=.0009). For every 10% decrease in TV from D1 to D43, the risk of death decreased by 44.3%. For patients whose TV decreased ≥39.3 or <39.3%, log-rank test demonstrated a separation in survival (P=.02), with median survivals of 31 months versus 10 months, respectively. Neither local recurrence (HR 0.791, 95% CI 0.51-1.23, P=.29), nor distant recurrence (HR 0.78, 95% CI 0.57-1.08, P=.137) correlated with TV decrease from D1 to D43. Histologic subtype showed no impact on our findings.
  
  
  CONCLUSIONS
  TV reduction as determined by CBCT during CRT as part of routine care predicts post-CRT survival. Such knowledge may justify intensification of RT or application of additional therapies. Assessment of genomic characteristics of these tumors may permit a better understanding of behavior or prediction of therapeutic outcomes.
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, Rutgers The State University of New Jersey, New Brunswick, New Jersey. Electronic address: jabbousk@cinj.rutgers.edu.
authors.forename: Salma K
authors.initials: SK
authors.lastname: Jabbour
authors.affiliation: Division of Biometrics, Rutgers Cancer Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, Rutgers The State University of New Jersey, New Brunswick, New Jersey; Department of Biostatistics, School of Public Health, Rutgers University, New Brunswick, New Jersey.
authors.forename: Sinae
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, Rutgers The State University of New Jersey, New Brunswick, New Jersey.
authors.forename: Syed A
authors.initials: SA
authors.lastname: Haider
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, Rutgers The State University of New Jersey, New Brunswick, New Jersey; Department of Radiation Oncology, The First Affiliated Hospital of Soochow University, Soochow, China.
authors.forename: Xiaoting
authors.initials: X
authors.lastname: Xu
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, Rutgers The State University of New Jersey, New Brunswick, New Jersey.
authors.forename: Alson
authors.initials: A
authors.lastname: Wu
authors.affiliation: Division of Medical Oncology, Rutgers Cancer Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, Rutgers The State University of New Jersey, New Brunswick, New Jersey.
authors.forename: Sujani
authors.initials: S
authors.lastname: Surakanti
authors.affiliation: Division of Medical Oncology, Rutgers Cancer Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, Rutgers The State University of New Jersey, New Brunswick, New Jersey.
authors.forename: Joseph
authors.initials: J
authors.lastname: Aisner
authors.affiliation: Division of Surgery, Rutgers Cancer Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, Rutgers The State University of New Jersey, New Brunswick, New Jersey.
authors.forename: John
authors.initials: J
authors.lastname: Langenfeld
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, Rutgers The State University of New Jersey, New Brunswick, New Jersey.
authors.forename: Ning J
authors.initials: NJ
authors.lastname: Yue
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, Rutgers The State University of New Jersey, New Brunswick, New Jersey.
authors.forename: Bruce G
authors.initials: BG
authors.lastname: Haffty
authors.affiliation: Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, Rutgers The State University of New Jersey, New Brunswick, New Jersey.
authors.forename: Wei
authors.initials: W
authors.lastname: Zou
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging / Q000401:mortality / Q000473:pathology / Q000556:secondary / Q000628:therapy; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging / Q000401:mortality / Q000473:pathology / Q000556:secondary / Q000628:therapy*; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000401:mortality / Q000473:pathology / Q000556:secondary / Q000628:therapy; D059248:Chemoradiotherapy / Q000401:mortality; D054893:Cone-Beam Computed Tomography; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D016016:Proportional Hazards Models; D011879:Radiotherapy Dosage; D061089:Radiotherapy, Image-Guided / Q000379:methods; D047368:Tumor Burden / Q000187:drug effects / Q000528:radiation effects