title: A new, effective, and safe therapeutic option using proton irradiation for hepatocellular carcinoma.
abstract: OBJECTIVE
  Conventional radiation is almost useless for hepatocellular carcinoma (HCC) because of the severe adverse effects of the irradiation to the accompanying liver cirrhosis. In contrast, the proton beam has Bragg peak, which limits distribution of the beam. The aim of this study was to prove the usefulness of proton irradiation for HCC.
  
  
  METHODS
  The proton irradiation was performed in 32 nodular lesions in 24 patients with HCC who had unresectable tumors or serious complications; the proton irradiation was performed either as monotherapy (15 lesions) or as combination therapy to insufficient Lipiodol-targeted chemotherapy (Kodama Co. Ltd., Tokyo, Japan) (17 lesions). The energy was 250 MeV, and 50-87 Gy (76.5 +/- 9.5, mean +/- SD) in total was irradiated for a time period of 17-69 days.
  
  
  RESULTS
  After 1 year, size reduction was seen in 12 out of 13 lesions (92%) in the monotherapy group and 9 out of 9 lesions (100%) in the combination therapy group; after 2 years, size reduction was seen 4 out of 5 lesions (80%) in the monotherapy group and 5 out of 5 lesions (100%) in the combination therapy group. Local tumor control has being assured for 2 years of the observation, which is continuing for another 2 years. None of the patients have experienced any serious adverse effects.
  
  
  CONCLUSIONS
  These results show that proton irradiation is a new, safe, and effective therapeutic option in cases of HCC, even in patients with unresectable tumors or those with serious complications.
authors.affiliation: Department of Medicine, University of Tsukuba, Ibaraki, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Matsuzaki
authors.forename: T
authors.initials: T
authors.lastname: Osuga
authors.forename: Y
authors.initials: Y
authors.lastname: Saito
authors.forename: Y
authors.initials: Y
authors.lastname: Chuganji
authors.forename: N
authors.initials: N
authors.lastname: Tanaka
authors.forename: J
authors.initials: J
authors.lastname: Shoda
authors.forename: H
authors.initials: H
authors.lastname: Tsuji
authors.forename: H
authors.initials: H
authors.lastname: Tsujii
mesh_terms: D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008113:Liver Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D061766:Proton Therapy; D011522:Protons / Q000009:adverse effects; D011832:Radiation Injuries; D016019:Survival Analysis; D014057:Tomography, X-Ray Computed; D000509:alpha-Fetoproteins / Q000032:analysis
chemical_list: D011522:Protons; D000509:alpha-Fetoproteins