The charts below detail relative risk and prevalence [1-6].
Relative Risk: The top chart shows approximate relative risk of developing invasive breast cancer by age 80 for a woman with a given risk factor compared to a woman without that risk factor: 1) disease-causing BRCA1 or -2 mutation; 2) prior ductal carcinoma in situ; 3) prior atypical ductal hyperplasia; 4) first-degree relative (mother or sister) diagnosed with breast cancer by age 50; 5) combined estrogen and progesterone therapy after menopause; 6) heterogeneously dense breast tissue (relative to a woman with fatty breasts); or 7) extremely dense breast tissue (relative to a woman with fatty breasts).
*The 15-year risk of developing invasive breast cancer among women with untreated DCIS (i.e. found on retrospective review of surgical biopsy specimens years later) is about 10 times greater than the risk in the general population [4, 5]. The risk 3 years or more after DCIS diagnosis in women who receive standard treatment is nearly 3 times greater than the risk in the general population [6].
Prevalence: The lower chart shows estimated prevalence of each risk factor in American women aged 40-74, except for hormone replacement therapy which applies only to postmenopausal women. Dense breast tissue is quite common, seen in 43% of all women aged 40-74.
References Cited
1. Cummings SR, Tice JA, Bauer S, et al. Prevention of breast cancer in postmenopausal women: Approaches to estimating and reducing risk. J Natl Cancer Inst2009; 101:384-398
2. Couch FJ, DeShano ML, Blackwood MA, et al. BRCA1 mutations in women attending clinics that evaluate the risk of breast cancer. N Engl J Med1997; 336:1409-1415
3. Sprague BL, Gangnon RE, Burt V, et al. Prevalence of mammographically dense breasts in the United States. J Natl Cancer Inst2014; 106
4. Page DL, Dupont WD, Rogers LW, Landenberger M. lntraductal carcinoma of the breast: follow-up after biopsy only. Cancer 1982; 49: 75 1-758
5. Betsill WL Jr, Rosen PP, Lieberman PH, Robbins GF. Intraductal carcinoma: Long-term follow-up after treatment by biopsy alone. JAMA 1978; 239:1863-1867
6. Mannu GS, Wang Z, Broggio J, et al. Invasive breast cancer and breast cancer mortality after ductal carcinoma in situ in women attending for breast screening in England, 1988-2014: population based observational cohort study. BMJ. 2020;369:m1570. doi: 10.1136/bmj.m1570