Routine screening mammography: how important is the radiation-risk side of the benefit-risk equation?
The potential radiation hazards associated with routine screening mammography, in terms of breast cancer induction, are discussed in the context of the potential benefits. The very low energy X-rays used in screening mammography (26-30 kVp) are expected to be more hazardous, per unit dose, than high-energy X- or gamma-rays, such as those to which A-bomb survivors (from which radiation risk estimates are derived) were exposed. Based on in vitro studies using oncogenic transformation and chromosome aberration end-points, as well as theoretical estimates, it seems likely that low doses of low-energy X-rays produce an increased risk per unit dose (compared with high energy photons) of about a factor of 2. Because of the low doses involved in screening mammography, the benefit-risk ratio for older women would still be expected to be large, though for younger women the increase in the estimated radiation risk suggests a somewhat later age than currently recommended--by about 5-10 years--at which to commence routine breast screening.
Brenner
D J
DJ
Center for Radiological Research, Columbia University, 630 West 168th Street, New York, NY 10032, USA. djb3@columbia.edu
Sawant
S G
SG
Hande
M P
MP
Miller
R C
RC
Elliston
C D
CD
Fu
Z
Z
Randers-Pehrson
G
G
Marino
S A
SA
D000328:Adult; D000367:Age Factors; D000818:Animals; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D002460:Cell Line / Q000528:radiation effects; D002869:Chromosome Aberrations; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D008327:Mammography / Q000009:adverse effects*; D008403:Mass Screening / Q000009:adverse effects*; D051379:Mice; D008809:Mice, Inbred C3H; D008875:Middle Aged; D009381:Neoplasms, Radiation-Induced / Q000209:etiology*; D017785:Photons; D012306:Risk; D018570:Risk Assessment; D013997:Time Factors; D014965:X-Rays