Smoking: the influence of carboxyhemoglobin (HbCO) on tumor oxygenation and response to radiation. [X rays; mice; transplantable KHT sarcomas]

Journal Article · Sun Jan 01 04:00:00 EST 1978 · Int. J. Radiat. Oncol., Biol. Phys.; (United States)

DOI:https://doi.org/10.1016/0360-3016(78)90189-X· OSTI ID:6540423

Siemann, D W; Hill, R P; Bush, R S

The effectiveness of localized x radiation on the transplantable KHT sarcoma was studied in nonanesthetized C3H mice possessing blood carboxyhemoglobin (HbCO) levels similar to those observed in heavy smokers. HbCO values of 10 percent were induced in tumor-bearing animals, either acutely just prior to irradiation or chronically during tumor growth and irradiation, by allowing the mice to breathe gas mixtures containing carbon monoxide (CO) in air. Tumors were irradiated either with single doses of 1500, 2000, or 2500 rad or with seven 500 rad fractions given at 24 hr intervals. Tumor cell survival was determined using an in vivo lung colony or an in vitro agar colony assay. The results with single doses of radiation indicate that under conditions of both acute and chronic exposure, the presence of 10 percent HbCO in the blood of the mice at the time of irradiation increases the survival of tumor cells in the hypoxic region of the survival curve by a factor of 2. During the fractionated irradiation, tumor cell survival in the presence of a 10 percent blood HbCO level (induced either acutely or chronically) was found to be significantly higher than that observed in air breathing mice. The results indicate that HbCO levels, such as are observed in heavy smokers, result in a larger fraction of hypoxic tumor cells. These findings suggest that heavy smoking prior to treatment may worsen the prognosis of patients undergoing radiotherapy.

• Research Organization: Ontario Cancer Inst., Toronto
• OSTI ID: 6540423
• Journal Information: Int. J. Radiat. Oncol., Biol. Phys.; (United States), Journal Name: Int. J. Radiat. Oncol., Biol. Phys.; (United States) Vol. 4:7-8; ISSN IOBPD
• Country of Publication: United States
• Language: English

Related Subjects

560151 -- Radiation Effects on Animals-- Man
560152* -- Radiation Effects on Animals-- Animals
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ACUTE EXPOSURE
ANIMAL CELLS
ANIMALS
ANOXIA
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CARBOXYHEMOGLOBIN
CHALCOGENIDES
CHRONIC EXPOSURE
DISEASES
ELECTROMAGNETIC RADIATION
FRACTIONATED IRRADIATION
INHALATION
INTAKE
IONIZING RADIATIONS
IRRADIATION
LOCAL IRRADIATION
MAMMALS
MICE
NEOPLASMS
OXIDES
OXYGEN COMPOUNDS
RADIATION EFFECTS
RADIATIONS
RADIOSENSITIVITY
RADIOSENSITIVITY EFFECTS
RODENTS
SARCOMAS
SURVIVAL CURVES
TRANSPLANTS
TUMOR CELLS
VERTEBRATES
X RADIATION