title: Variation of the relative biologic effectiveness with tumor size using accelerated helium ions.
abstract: The RBE of an accelerated helium ion beam was determined on murine osteosarcomas ranging in size from single cells to visibly detectable lung colonies of approximately 1 X 10(-2) mm3. That the RBE increased as tumor size increased provides some biologic basis for the selection of advanced cases of neoplasia for clinical trials using relatively high LET radiation sources.
mesh_terms: D000818:Animals; D003037:Cobalt Radioisotopes; D006371:Helium; D007477:Ions; D008175:Lung Neoplasms / Q000532:radiotherapy*; D051379:Mice; D009362:Neoplasm Metastasis; D009374:Neoplasms, Experimental / Q000532:radiotherapy; D012516:Osteosarcoma / Q000532:radiotherapy*; D011867:Radioisotope Teletherapy; D011868:Radioisotopes; D013997:Time Factors
chemical_list: D003037:Cobalt Radioisotopes; D007477:Ions; D011868:Radioisotopes; D006371:Helium