Breast Cancer and Radiation (Part 1)
In our modern world of high-tech medicine, exposure to ionising radiation in the course of medical diagnosis is increasingly common. X-rays, mammograms, and Cat-scans are routinely used to peer into the body. Despite their routine use, all these procedures expose our cells to ionising radiation, for which a safe exposure level has never been established. Even the lowest doses of radiation can damage the genetic material within a cell, increasing the risk of abnormal cell replication and the development of cancer. In fact, exposure to ionizing radiation is one of the few irrefutable causes of cancer. Prominent researchers such as Dr John Gofman, and well known breast specialist Dr Susan Love go as far as to suggest that some of the modern escalation in breast cancer incidence can be accounted for by previous exposure to medical radiation. Between 1950 and 1990 breast cancer incidence soared by 90% in America, with similar increases seen in other western countries. How much of this rapid increase is related to radiation exposure, will never be certain.
In 1993 the Journal of the National Cancer Institute concluded that “total dose, age at first exposure, and time since first exposure are all determinants of the incidence rate ratio of breast cancer after exposure of the breast to ionizing radiation”. Time of exposure to radiation influences how great a negative impact there will be on breast tissue. Radiation exposure during childhood is thought to impart the greatest cancer risk, with exposure after the age of 40 having much less of an impact. Adolescent girls undergoing rapid breast tissue development are at the most risk of radiation damage to breast tissue
A fact sheet from Cornell University states “age at exposure is one of the most important determinants of future risk of developing breast cancer due to radiation later in life. Young girls are at highest risk and women irradiated around the menopausal ages are at low risk”. Before menopause, breast tissue has an increased sensitivity to radiation, possibly due to higher estrogen levels, so cumulative exposure to radiation prior to menopause poses a greater risk than the same cumulative exposure after the menopause.
While one exposure to radiation may not significantly increase our risk of breast cancer, cumulative exposures almost certainly do. Modern X-rays and mammograms deliver about ten times fewer rads than their earlier ancestors, but their cumulative impact is still of concern. When it comes to X-rays it is X-rays of the chest and coronary X-rays which pose the greatest risk to the breasts. However, radiation can scatter from X-rays anywhere in the body, including dental X-rays, to effect the breasts (Always request a lead apron be used for dental X-rays).
CT scans are now widely used in medical diagnosis, despite the fact that the radiation exposure from CT scans is many times greater than from an X-ray. The American National Cancer Institute says “CT scans comprise about 10% of diagnostic radiological procedures in US hospitals, but contribute an estimated 65% of effective radiation dose to the public from all medical X ray equipment”. Professor Eric Hall, from Columbia University, New York, says that a modern CT scan will expose a patient to the same amount of radiation as the inhabitants of Hiroshima and Nagasaki were exposed to!
(CONTINUED IN PART 2)
To Your Wellbeing…
Lynda Wharton