Combination therapy with 1,3-bis(2-chloroethyl)-1-nitrosourea and low dose rate radiation in the 9L rat brain tumor and spheroid models: implications for brain tumor brachytherapy

Journal Article · Sat Dec 01 04:00:00 EST 1984 · Neurosurgery; (United States)

DOI:https://doi.org/10.1227/00006123-198412000-00002· OSTI ID:5777666

Gutin, P H; Bernstein, M; Sano, Y; Deen, D F

The effects of combination treatment with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and low dose rate radiation were studied in the 9L rat brain tumor in vivo model and the 9L multicellular tumor spheroid model. F-344 rats bearing intracerebral 9L gliosarcomas were implanted with removable /sup 125/I sources. Minimal (peripheral) tumor doses of 6387 rad produced an increased life-span (ILS) of 28% over that of control rats implanted with dummy sources, BCNU alone (13.3 mg/kg) produced in an ILS of 67%, and combination treatment with BCNU and implanted /sup 125/I sources produced an ILS of 167%. As measured by a colony-forming efficiency assay, the greatest cell kill in 9L spheroids occurred when BCNU was administered 24 hours before irradiation from a /sup 137/Cs source at a low dose rate of 5 rad/minute. At a higher dose rate of 210 rad/minute, the time dependence of the effects of combination treatment was identical and therefore independent of dose rate.

• Research Organization: Univ. of California, San Francisco
• OSTI ID: 5777666
• Journal Information: Neurosurgery; (United States), Journal Name: Neurosurgery; (United States) Vol. 15:6; ISSN NRSRD
• Country of Publication: United States
• Language: English

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62 RADIOLOGY AND NUCLEAR MEDICINE
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALKALI METAL ISOTOPES
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BIOLOGICAL MODELS
BODY
BRAIN
CELL KILLING
CENTRAL NERVOUS SYSTEM
CESIUM 137
CESIUM ISOTOPES
DAYS LIVING RADIOISOTOPES
DISEASES
DOSES
ELECTRON CAPTURE RADIOISOTOPES
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPES
MAMMALS
MEDICINE
NEOPLASMS
NERVOUS SYSTEM
NITROSO COMPOUNDS
NITROSOUREAS
NUCLEAR MEDICINE
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
RADIATION DOSES
RADIOISOTOPES
RADIOLOGY
RADIOTHERAPY
RATS
RODENTS
SARCOMAS
SURVIVAL TIME
SYNERGISM
THERAPY
VERTEBRATES
YEARS LIVING RADIOISOTOPES