STUDIES ON RADIATION-INDUCED MAMMARY GLAND NEOPLASIA IN THE RAT. VII. THE EFFECTS OF FRACTIONATION AND PROTRACTION OF SUBLETHAL TOTAL-BODY IRRADIATION

Journal Article · Sun Jul 01 04:00:00 EDT 1962 · Radiation Research

DOI:https://doi.org/10.2307/3571214· OSTI ID:4827722

Shellabarger, C. J.; Bond, V. P.; Cronkite, E. P.

Female Sprague-Dawley rats were given a total-body exposure of 400 r of 250-kvp x rays either in a single dose, in five successive daily exposures, or in eighteen successive daily exposures, the mid-point of each exposure being the fortieth day of age. The cumulative incidence of mammary neoplasms 12 months later was: 24/31 = 77%; differ statistically from one to the other but were clearly greater than the 3/31 = 10% incldence in the controls. The incidence of nonmammary tissue neoplasia did not exceed 6% in any group, and no conclusions could be drawn about the effect of fractionation and protraction on this response. It was concluded that within the limits of the experiment the neoplastic response of rat mammary tissue was independent of fractionation and protraction and thus is not inconsistent with a nonthreshold direct mechanism for the primary event leading to neoplasia induction by sublethal to total-body irradiation. (auth)

• Research Organization: Brookhaven National Lab., Upton, N.Y.
• NSA Number: NSA-16-021982
• OSTI ID: 4827722
• Report Number(s): BNL-5815
• Journal Information: Radiation Research, Journal Name: Radiation Research Vol. Vol: 17
• Country of Publication: United States
• Language: English

Related Subjects

AGE
BIOLOGY AND MEDICINE
BODY
CARCINOGENESIS
GLANDS
MAMMARY GLANDS
RADIATION DOSES
RATS
TUMORS
X RADIATION