Biomaterial Database

Pions for radiotherapy at TRIUMF. 1980

L D Skarsgard, and R M Henkelman, and C J Eaves

Beams of negative pi-mesons (pions) have depth-dose characteristics which are favorable for radiation therapy. As well, the densely ionizing radiations resulting from pion capture give pion beams an increased RBE and reduced OER, largely confined to the treatment volume. Three facilities capable of testing pion beams for therapy now exist: TRIUMF in Vancouver, LAMPF in New Mexico and SIN in Villigen, Switzerland. Patient treatment is already underway at LAMPF and will commence at TRIUMF in November, 1979, and at SIN in 1980. Pre-clinical studies of the pion beam at TRIUMF have confirmed the predicted physical and radiobiologic properties of this new type of radiation. Fractionated irradiation of mouse skin suggests an RBE of 1.4 -- 1.6 for small treatment volumes receiving 10 dose fractions of peak pions. Single dose studies with cultured cells give an RBE for peak pions of 1.2 -- 1.5 and an oxygen gain factor of 1.2. The results are generally in good agreement with those obtained at LAMPF and SIN. Techniques have been developed which facilitate the delivery of well-defined dose distributions with uniform biologic effect throughout the treatment volume.

UI	MeSH Term	Description	Entries
D010101	Oxygen Consumption	The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)	Consumption, Oxygen,Consumptions, Oxygen,Oxygen Consumptions
D010315	Particle Accelerators	Devices which accelerate electrically charged atomic or subatomic particles, such as electrons, protons or ions, to high velocities so they have high kinetic energy.	Betatrons,Linear Accelerators,Accelerator, Linear,Accelerator, Particle,Accelerators, Linear,Accelerators, Particle,Betatron,Linear Accelerator,Particle Accelerator
D010825	Physics	The study of those aspects of energy and matter in terms of elementary principles and laws. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Physic
D011829	Radiation Dosage	The amount of radiation energy that is deposited in a unit mass of material, such as tissues of plants or animal. In RADIOTHERAPY, radiation dosage is expressed in gray units (Gy). In RADIOLOGIC HEALTH, the dosage is expressed by the product of absorbed dose (Gy) and quality factor (a function of linear energy transfer), and is called radiation dose equivalent in sievert units (Sv).	Sievert Units,Dosage, Radiation,Gray Units,Gy Radiation,Sv Radiation Dose Equivalent,Dosages, Radiation,Radiation Dosages,Units, Gray,Units, Sievert
D011853	Radiobiology	Study of the scientific principles, mechanisms, and effects of the interaction of ionizing radiation with living matter. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Radiation Biology,Biology, Radiation
D011878	Radiotherapy	The use of IONIZING RADIATION to treat malignant NEOPLASMS and some benign conditions.	Radiotherapy, Targeted,Targeted Radiotherapy,Radiation Therapy,Radiation Therapy, Targeted,Radiation Treatment,Targeted Radiation Therapy,Radiation Therapies,Radiation Therapies, Targeted,Radiation Treatments,Radiotherapies,Radiotherapies, Targeted,Targeted Radiation Therapies,Targeted Radiotherapies,Therapies, Radiation,Therapies, Targeted Radiation,Therapy, Radiation,Therapy, Targeted Radiation,Treatment, Radiation
D011879	Radiotherapy Dosage	The total amount of radiation absorbed by tissues as a result of radiotherapy.	Dosage, Radiotherapy,Dosages, Radiotherapy,Radiotherapy Dosages
D012062	Relative Biological Effectiveness	The ratio of radiation dosages required to produce identical change based on a formula comparing other types of radiation with that of gamma or roentgen rays.	Biological Effectiveness, Relative,Effectiveness, Biologic Relative,Effectiveness, Biological Relative,Relative Biologic Effectiveness,Biologic Effectiveness, Relative,Biologic Relative Effectiveness,Biological Relative Effectiveness,Effectiveness, Relative Biologic,Effectiveness, Relative Biological,Relative Effectiveness, Biologic
D001955	British Columbia	A province of Canada on the Pacific coast. Its capital is Victoria. The name given in 1858 derives from the Columbia River which was named by the American captain Robert Gray for his ship Columbia which in turn was named for Columbus. (From Webster's New Geographical Dictionary, 1988, p178 & Room, Brewer's Dictionary of Names, 1992, p81-2)
D002470	Cell Survival	The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.	Cell Viability,Cell Viabilities,Survival, Cell,Viabilities, Cell,Viability, Cell