Breast Cancer Screening: Who Needs More?

Early detection decreases mortality for women with breast cancer.  Women at higher than average risk of breast cancer may benefit from supplemental breast cancer screening.  Questions?  We have answers.

Why do we offer screening mammography?  The goal of breast cancer screening is to reduce deaths from breast cancer by detecting it early, when treatment is more effective and less harmful. Mammography is the only test proven to reduce breast cancer mortality.  Breast cancer accounts for almost a 1/3 (29%) of new cancer diagnoses and is the 2nd leading cause of cancer related death among women in the United States. Mammography screening decreases breast cancer deaths by roughly a third in all women ages 40 and over.

When should a women start undergoing screening mammography and for how long?   Annual screening beginning at age 40 will save the most lives.  Annual screening yields a greater benefit, particularly for younger women, whose cancers have faster growth rates.  Check out: or sbi-online/endtheconfusion.  Higher-risk women should start mammographic screening earlier and may benefit from supplemental screening modalities, like magnetic resonance imaging (MRI) or ultrasound.

Are there Population Subgroups at Higher Risk for Breast Cancer?  Yes!  Several factors can increase a women’s risk for breast cancer.  Certain genetic mutations are associated with an increased risk of developing breast cancer.  The most widely recognized genetic mutations include BRCA 1 and BRCA2 mutation, with a lifetime risk of developing breast cancer 50-85% among BRCA1 carriers and approximately 45% in BRCA2 carriers.  Other less common gene mutations include TP53, CHEK2 (Li-Fraumeni syndrome), PTEN (Cowden and Bannayan-Riley-Ruvalcaba syndromes), CDH1 (hereditary diffuse gastric cancer), STK11 (Peutz-Jeghers syndrome), PALB2, and ATM genes.

When should a woman undergo evaluation to assess for breast cancer risk?   All women, especially black women and those of Askenazi Jewish descent should be evaluated for breast cancer risk no later than age 30, so that those at higher risk can be identified and can benefit from supplemental screening.

Am I at higher risk if I have family history of breast cancer?   Maybe.  Even in the absence of known genetic mutations, women with strong family histories are at higher risk.  The number of family members with breast cancer, especially first degree relatives and their ages at diagnosis are important considerations that add to the complexity to the assessment. 

Am I at higher risk if I have had breast cancer?  Yes.  Women with personal histories of breast cancer are at risk for recurrence of a second breast cancer, with a risk of a contralateral cancer ranging between 0.5%-1% per year during the ten years after diagnosis. Age at diagnosis maters. Women diagnosed at or before age of 50 and treated with breast conserving therapy have a 20% of higher lifetime risk for a new breast cancer.  Women with history of lobular neoplasia (LCIS or ALH) also have a lifetime risk ranging between 10-20%.

Who should consider supplemental breast MRI for breast cancer screening? For women with genetics based increased risk (and their untested first-degree relatives), a history of chest radiation (cumulative dose >10 Gy before age of 30), or with a calculated lifetime risk of 20% or more, breast MRI should be performed annually beginning at age 25 to 30 years of age.  For women with personal histories of breast cancer and dense breast tissue or those diagnosed before age of 50, annual surveillance with breast MRI is recommended.  For women with personal histories of breast cancer or with LCIS or atypia on prior biopsy, MRI should be considered especially if other risk factors are present.*

Who should consider supplemental whole breast screening breast ultrasound for breast cancer screening?  Women with elevated risk who would qualify but cannot undergo breast MRI should consider adjunctive screening with ultrasound.  For women with elevated risk limited to increase breast density, ultrasound can also be considered for adjunctive screening after weighing the benefits and risks.

Is breast density related to my risk for developing breast cancer?  Yes, breast density is a strong predictors of breast cancer risk.  A woman with extremely dense breast density has a 4-6 times increase risk of developing breast cancer as a woman with fatty breasts and almost two times increase risk of developing breast cancer as a woman with scattered fibroglandular breast density.  Density assessment may vary by radiologist and from year to year, and apparent changes may be affected by weight gain or weight loss and the use of withdrawl of endocrine therapy.

 *BREAKING NEWS –  a recent study shows abbreviated MRI is better than 3D mammograms at detecting breast cancer in women with dense breasts. Follow the links to opens in a new windowread the complete study or opens in a new windowread a news release on the study.