(RxWiki News) It’s a conundrum — dense breast tissue makes it harder to detect cancer in a mammogram, but it also raises the risk of breast cancer. For women with dense breast tissue, breast cancer risk education may help more than required screening.
Although some states have passed laws on this issue, a new commentary from three Harvard Medical School radiologists suggests that laws are not a good answer. More intensive screening can result in false positives and overtreatment, these radiologists said.
These radiologists said states should carefully analyze the risks and benefits of additional screening before increasing regulations for supplemental screening.
Lead author Priscilla J. Slanetz, MD, director of breast imaging research and education at Beth Israel Deaconess Medical Center and an associate professor at Harvard Medical School in Boston, wrote in a press release, "Given recent concerns raised by the US Preventive Services Task Force about false positives and increased patient anxiety with even routine mammography screening, widespread supplemental screening for all women with dense breast tissue without careful consideration of the risks and benefits would be unwise.”
Dense breast tissue contains more of a type of tissue called fibroglandular tissue than fatty tissue. Women who have dense breast tissue also have an increased risk of breast cancer.
Dr. Slanetz and team noted that a woman with dense breast tissue has a breast cancer risk between 1.2 and 2.1 times higher than a woman with average breast density. But other factors should be considered, Dr. Slanetz and team said. For instance, women with close relatives like sisters or mothers who have had breast cancer may have double the risk of breast cancer, regardless of the composition of the breast tissue.
Genetic mutations called BRCA1 or BRCA2 can also increase the risk of breast cancer. If a woman has a relative who is known to carry either mutation, her breast cancer risk goes up eight-fold.
Laws on screening dense breast tissue vary from one state to another. What all have in common, however, is that doctors who perform mammography must notify women if they have dense breast tissue. These doctors must also tell the patients that dense breast tissue increases their risk of breast cancer.
Some states require women with dense breast tissue to undergo screening with a breast ultrasound. A small number require that insurance cover the ultrasound.
In an interview with Stephen Morrissey, managing editor of the New England Journal of Medicine, Dr. Slanetz said that patient compliance with follow-up ultrasounds varies. The use of ultrasounds is also variable, according to Dr. Slanetz, and false positives occur relatively often, which can be stressful for the patient.
Dr. Slanetz stressed in the interview that each patient and her doctor should discuss all of the relevant issues and risks before deciding on screening frequency and follow-ups with either ultrasound or breast MRI.
Dr. Slanetz and her colleagues noted in their article that supplemental screening should be based on medical evidence. At this point, they said, evidence supports mammography screening and the use of breast MRI — but not ultrasound screening.
These authors noted in their article that overdiagnosis and overtreatment should also concern doctors.
"Having dense breast tissue increases a women's lifetime risk of breast cancer, but it's important for health care providers to place this risk in perspective for each patient," Dr. Slanetz said in the press release. "At present, risk [knowledge] is likely going to help guide recommendations regarding which women might benefit from supplemental screening, regardless of their breast density. This conversation also offers an opportunity to engage women in their own health care and forge stronger patient-doctor relationships."
The article by Dr. Slanetz and team was published Feb. 11 in the New England Journal of Medicine.
Dr. Slanetz and colleagues disclosed no funding sources or conflicts of interest.