title: Do we have enough evidence to implement particle therapy as standard treatment in lung cancer? A systematic literature review.
abstract: BACKGROUND
  The societal burden of lung cancer is high because of its high incidence and high lethality. From a theoretical point of view, radiotherapy with beams of protons and heavier charged particles, for example, carbon ions (C-ions), should lead to superior results, compared with photon beams. In this review, we searched for clinical evidence to justify implementation of particle therapy as standard treatment in lung cancer.
  
  
  METHODS
  A systematic literature review based on an earlier published comprehensive review was performed and updated through November 2009.
  
  
  RESULTS
  Eleven fully published studies, all dealing with non-small cell lung cancer (NSCLC), mainly stage I, were identified. No phase III trials were found. For proton therapy, 2- to 5-year local tumor control rates varied in the range of 57%-87%. The 2- and 5-year overall survival (OS) and 2- and 5-year cause-specific survival (CSS) rates were 31%-74% and 23% and 58%-86% and 46%, respectively. Radiation-induced pneumonitis was observed in about 10% of patients. For C-ion therapy, the overall local tumor control rate was 77%, but it was 95% when using a hypofractionated radiation schedule. The 5-year OS and CSS rates were 42% and 60%, respectively. Slightly better results were reported when using hypofractionation, 50% and 76%, respectively.
  
  
  CONCLUSIONS
  The present results with protons and heavier charged particles are promising. However, the current lack of evidence on the clinical (cost-)effectiveness of particle therapy emphasizes the need to investigate the efficiency of particle therapy in an adequate manner. Until these results are available for lung cancer, charged particle therapy should be considered experimental.
authors.affiliation: Maastricht Radiation Oncology (MAASTRO) Clinic, Dr. Tanslaan 12, 6229 ET Maastricht, The Netherlands. madelon.pijls@maastro.nl
authors.forename: Madelon
authors.initials: M
authors.lastname: Pijls-Johannesma
authors.forename: Janneke P C
authors.initials: JP
authors.lastname: Grutters
authors.forename: Frank
authors.initials: F
authors.lastname: Verhaegen
authors.forename: Philippe
authors.initials: P
authors.lastname: Lambin
authors.forename: Dirk
authors.initials: D
authors.lastname: De Ruysscher
mesh_terms: D002250:Carbon Radioisotopes / Q000627:therapeutic use*; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality* / Q000473:pathology / Q000532:radiotherapy*; D002986:Clinical Trials as Topic; D019583:Dose Fractionation, Radiation; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality* / Q000473:pathology / Q000532:radiotherapy*; D061766:Proton Therapy; D011788:Quality of Life; D011878:Radiotherapy / Q000009:adverse effects; D011879:Radiotherapy Dosage
chemical_list: D002250:Carbon Radioisotopes