Mm. Doody et al., EMPLOYMENT PRACTICES AND BREAST-CANCER AMONG RADIOLOGIC TECHNOLOGISTS, Journal of occupational and environmental medicine, 37(3), 1995, pp. 321-327
A case-control study of breast cancer and employment practices among f
emale radiologic technologists was conducted. The cohort from which ca
ses and controls were derived included over 105,000 female medical rad
iation workers certified by the American Registry of Radiologic Techno
logists during 1926-1980. Breast cancer cases (n = 528) were individua
lly matched to an average of five control subjects (n = 2628) based on
year of birth, year of certification, and length of follow-up. Proced
ures most commonly performed by controls included fluoroscopy (93%), p
ortable radiographs (92%), routine radiographs (92%), multifilm proced
ures (87%), dental x-rays (46%), radium therapy (31%), orthovoltage (2
3%), and cobalt-60 (21%). Breast cancer was not significantly increase
d with occupational experience with any of these procedures. Furthermo
re, risk was not related to number of years worked with a particular p
rocedure. This study is reassuring in indicating that medical radiatio
n workers are not at substantial risk for developing radiation-induced
breast cancer. However, because only surrogate measures of radiation
exposure were available, possibility of a small risk cannot be discoun
ted. Ongoing follow-up of this cohort for incident cancers will incorp
orate detailed exposure assessment schemes, providing additional infor
mation on effects of long-term low-dose radiation, through occupation.