Nuclear-based breast imaging tests could increase the risk of radiation-induced cancer, reports a new study.
However, the radiation dose and risk from mammography are very low.
"A single breast-specific gamma imaging (BSGI) or positron emission mammography (PEM) examination carries a lifetime risk of inducing fatal cancer greater than or comparable to a lifetime of annual screening mammography starting at age 40," said the study's author, R. Edward Hendrick, clinical professor of radiology at the University of Colorado-Denver, School of Medicine in Aurora, Co.
The risks and benefits of screening mammography are under constant scrutiny. Meanwhile, newer breast imaging technologies, such as BSGI and PEM have been approved by the U.S. Food and Drug Administration (FDA) and introduced into clinical practice.
Preliminary studies have shown both to be promising at detecting cancer; however, both involve the injection of radioactive material into the patient.
BSGI uses a high-resolution gamma camera that allows for imaging with mild compression of the breast along with an injection of a nuclear radiotracer, which is absorbed at a higher rate by cancerous cells.
In PEM, radioactive material is injected into the body to measure metabolic activity and determine the presence of disease. Other technologies, not yet approved by the FDA, include dedicated breast CT and digital breast tomosynthesis.
Dr. Hendrick reviewed recent studies on radiation doses from radiologic procedures and organ doses from nuclear medicine procedures, along with Biologic Effects of Ionizing Radiation (BEIR) VII age-dependent risk data, to estimate the lifetime risk of radiation-induced cancer incidence and death from breast imaging exams using ionizing radiation.
