title: Reirradiation and stereotactic radiotherapy for tumors in the lung: dose summation and toxicity.
abstract: OBJECTIVE
  To assess the accumulated dose and the toxicity after reirradiation for tumors in the lung using non-rigid registration.
  
  
  METHODS
  Twenty patients with a tumor in the lung were reirradiated with or after stereotactic radiotherapy. The summed dose distribution was calculated using non-rigid registration. All doses were recalculated to an equivalent dose of 2 Gy per fraction (EQD2). The median follow-up time was 12 months (range 2-52).
  
  
  RESULTS
  The median Dmax of the lung in the summed plans was 363 Gy3 (range 123-590). The median accumulated V20 of the lungs was 15.2%. Seven patients had in the heart and the trachea an accumulated dose ≥70 Gy3, with a median D(max) of the heart of 115 Gy3 and 89 Gy3 for the trachea. Eight patients had in the esophagus an accumulated dose ≥70 Gy3, with a median accumulated dose of 85 Gy3. No grade 3-5 toxicity was observed.
  
  
  CONCLUSIONS
  Reirradiation of the lung with or after stereotactic radiotherapy is feasible to a median Dmax of 363 Gy3 to the lung, as low toxicity was observed.
authors: Department of Radiation Oncology, Erasmus MC-Daniel den Hoed Cancer Center, Rotterdam, The Netherlands.
authors: Thomas R
authors: TR
authors: Meijneke
authors: Steven F
authors: SF
authors: Petit
authors: Davy
authors: D
authors: Wentzler
authors: Mischa
authors: M
authors: Hoogeman
authors: Joost J
authors: JJ
authors: Nuyttens
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004947:Esophagus / Q000528:radiation effects; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D058958:Organs at Risk; D016634:Radiosurgery / Q000009:adverse effects; D011879:Radiotherapy Dosage; D047368:Tumor Burden
keywords: Dose accumulation; Lung cancer; Reirradiation; Toxicity