title: Esophagus and Contralateral Lung-Sparing IMRT for Locally Advanced Lung Cancer in the Community Hospital Setting.
abstract: BACKGROUND
  The optimal technique for performing lung IMRT remains poorly defined. We hypothesize that improved dose distributions associated with normal tissue-sparing IMRT can allow safe dose escalation resulting in decreased acute and late toxicity.
  
  
  METHODS
  We performed a retrospective analysis of 82 consecutive lung cancer patients treated with curative intent from 1/10 to 9/14. From 1/10 to 4/12, 44 patients were treated with the community standard of three-dimensional conformal radiotherapy or IMRT without specific esophagus or contralateral lung constraints (standard RT). From 5/12 to 9/14, 38 patients were treated with normal tissue-sparing IMRT with selective sparing of contralateral lung and esophagus. The study endpoints were dosimetry, toxicity, and overall survival.
  
  
  RESULTS
  Despite higher mean prescribed radiation doses in the normal tissue-sparing IMRT cohort (64.5 vs. 60.8 Gy, p = 0.04), patients treated with normal tissue-sparing IMRT had significantly lower lung V20, V10, V5, mean lung, esophageal V60, and mean esophagus doses compared to patients treated with standard RT (p ≤ 0.001). Patients in the normal tissue-sparing IMRT group had reduced acute grade ≥3 esophagitis (0 vs. 11%, p < 0.001), acute grade ≥2 weight loss (2 vs. 16%, p = 0.04), and late grade ≥2 pneumonitis (7 vs. 21%, p = 0.02). The 2-year overall survival was 52% with normal tissue-sparing IMRT arm compared to 28% for standard RT (p = 0.015).
  
  
  CONCLUSIONS
  These data provide proof of principle that suboptimal radiation dose distributions are associated with significant acute and late lung and esophageal toxicity that may result in hospitalization or even premature mortality. Strict attention to contralateral lung and esophageal dose-volume constraints are feasible in the community hospital setting without sacrificing disease control.
authors.affiliation: Department of Radiation Oncology, Good Samaritan Hospital Medical Center , West Islip, NY , USA.
authors.forename: Johnny
authors.initials: J
authors.lastname: Kao
authors.affiliation: Department of Radiation Oncology, Good Samaritan Hospital Medical Center , West Islip, NY , USA.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Pettit
authors.affiliation: Department of Radiation Oncology, Good Samaritan Hospital Medical Center , West Islip, NY , USA.
authors.forename: Soombal
authors.initials: S
authors.lastname: Zahid
authors.affiliation: Division of Hematology and Medical Oncology, Good Samaritan Hospital Medical Center , West Islip, NY , USA.
authors.forename: Kenneth D
authors.initials: KD
authors.lastname: Gold
authors.affiliation: Department of Surgery, Good Samaritan Hospital Medical Center , West Islip, NY , USA.
authors.forename: Terry
authors.initials: T
authors.lastname: Palatt
keywords: chemoradiation; dose distribution; intensity-modulated radiation therapy; lung cancer; toxicity