title: Comparative study of dose distributions and cell survival fractions for 1H, 4He, 12C and 16O beams using Geant4 and Microdosimetric Kinetic model.
abstract: Depth and radial dose profiles for therapeutic (1)H, (4)He, (12)C and (16)O beams are calculated using the Geant4-based Monte Carlo model for Heavy-Ion Therapy (MCHIT). (4)He and (16)O ions are presented as alternative options to (1)H and (12)C broadly used for ion-beam cancer therapy. Biological dose profiles and survival fractions of cells are estimated using the modified Microdosimetric Kinetic model. Depth distributions of cell survival of healthy tissues, assuming 10% and 50% survival of tumor cells, are calculated for 6 cm SOBPs at two tumor depths and for different tissues radiosensitivities. It is found that the optimal ion choice depends on (i) depth of the tumor, (ii) dose levels and (iii) the contrast of radiosensitivities of tumor and surrounding healthy tissues. Our results indicate that (12)C and (16)O ions are more appropriate to spare healthy tissues in the case of a more radioresistant tumor at moderate depths. On the other hand, a sensitive tumor surrounded by more resistant tissues can be better treated with (1)H and (4)He ions. In general, (4)He beam is found to be a good candidate for therapy. It better spares healthy tissues in all considered cases compared to (1)H. Besides, the dose conformation is improved for deep-seated tumors compared to (1)H, and the damage to surrounding healthy tissues is reduced compared to heavier ions due to the lower impact of nuclear fragmentation. No definite advantages of (16)O with respect to (12)C ions are found in this study.
authors.affiliation: Frankfurt Institute for Advanced Studies, Johann Wolfgang Goethe University, 60438 Frankfurt am Main, Germany. Institut für Theoretische Physik, Johann Wolfgang Goethe University, 60438 Frankfurt am Main, Germany.
authors.forename: Lucas
authors.initials: L
authors.lastname: Burigo
authors.forename: Igor
authors.initials: I
authors.lastname: Pshenichnov
authors.forename: Igor
authors.initials: I
authors.lastname: Mishustin
authors.forename: Marcus
authors.initials: M
authors.lastname: Bleicher
mesh_terms: D002250:Carbon Radioisotopes / Q000627:therapeutic use; D002470:Cell Survival / Q000528:radiation effects*; D002478:Cells, Cultured; D063193:Heavy Ion Radiotherapy; D006371:Helium / Q000627:therapeutic use; D006801:Humans; D006859:Hydrogen / Q000627:therapeutic use; D007700:Kinetics; D008962:Models, Theoretical; D009010:Monte Carlo Method; D010104:Oxygen Radioisotopes / Q000627:therapeutic use; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D013363:Submandibular Gland / Q000166:cytology / Q000528:radiation effects*; D013365:Submandibular Gland Neoplasms / Q000473:pathology / Q000532:radiotherapy*
chemical_list: D002250:Carbon Radioisotopes; D010104:Oxygen Radioisotopes; D006371:Helium; D006859:Hydrogen