Monday, June 9, 2014

Should I have a mammogram?

Nearly every day a patient will ask when she should have her first mammogram.  In our practice, we follow the American Cancer Society guideline that recommends women have their first screening mammogram at age 40 and annually thereafter even if no family history of breast cancer or breast symptoms. The exception to this is for women who have a first degree relative (mother or sister) who developed breast cancer before age 50.  Those women should start screening 10 years before youngest age of diagnosis.  For example, if a woman is age 30 and her mother developed breast cancer at age 42, she should have her first mammogram at age 32 and annually thereafter.  The reason that women generally should not have their mammogram before age 40 is that breast tissue is very dense which makes it more difficult to detect even very small tumors.  If a concern arises such as a palpable lump, our clinicians will generally order breast ultrasound.  Depending on age and circumstances, some radiologists will also require that a diagnostic mammogram be performed before the ultrasound.

Mammograms are X-rays of the breast.  The gold standard for mammograms is the digital mammogram where the images are stored electronically.  The newest technology is 3D mammography also known as Digital Breast Tomosynthesis.  3D is similar to a CT of the breast and is performed in conjunction with a standard digital mammogram. The mammogram is performed the same way but additional images are captured that break the breast tissue down into more layers or "slices."  The advantage of 3D is that images can better differentiate abnormal from normal tissue.  In digital mammography there can be an "overlap" of breast tissue that may result in a call to the patient to return for additional views which can cause psychological distress. The disadvantage of 3D is that, because more images are taken, radiation exposure is slightly higher. It is also not yet covered by insurance so costs about $75 more than digital mammography alone. At present, only one hospital in Omaha offers 3D imaging.  I encourage women who are going for their baseline mammogram, have dense breast tissue or have a strong family of breast cancer or tested positive for BRCA gene mutations to consider 3D mammography.  Those positive for gene mutation(s) would also qualify for breast MRI annually in addition to mammography.  We offer testing for BRCA gene mutations in our clinic to identify those women who might be at high genetic risk for breast cancer.

Some women hesitate to have a mammogram because they are worried about the pain due to breast compression or excessive exposure to radiation that might actually cause cancer. While there is some discomfort, most women acknowledge that it is short-lived and they do not find it intolerable.  Radiation exposure is also very minimal. A digital mammogram is  0.1 to 0.2 rads (a rad is a measure of radiation) per x-ray. To put that into perspective, a woman who has an annual mammogram from age 40 to 90 would be exposed to a total of 20 to 40 rads and 1-3xs higher if 3D is utilized.  A woman being treated for breast cancer, however, may receive 5000 rads!

Although there has been a lot of controversy swirling in the media in the recent past regarding the benefit of mammography especially before the age of 50,  it remains the gold standard for early detection of breast cancer which then impacts her chance of survival.