Search

Due to an increasing comorbidity burden with aging, the margin of benefit from screening mammography in women ages ≥65 is highly variable. This study examined 10-year cumulative risk of non-breast cancer mortality and breast cancer by comorbidity and age in a screening population. Methods: We used prospective cohort data from the Breast Cancer Surveillance Consortium (BCSC), which included 198,362 women ages ≥65 years who have undergone at least one screening mammogram. We calculated cumulative incidence of non-breast cancer mortality and risk of breast cancer 10 years following the screening mammogram for women ages 65-74, 75-84 and ≥85 years stratified by the Charlson Comorbidity Index (CCI scores 0, 1 and ≥2). Results: During a median follow-up time of 8.1 years (interquartile range, 4.6 to 10 years), 34,768 died from non-breast cancer causes and 6,327 women were diagnosed with invasive breast cancer of whom 359 died from breast cancer and 942 from non-breast cancer causes. The 10-year cumulative risk of invasive breast cancer following a screening mammogram did not significantly decrease with elevating CCI score and age for women ages 65-74 [CCI 0 = 4.0% (95% CI, 3.9%-4.1%) vs. CCI ≥2 = 3.8% (95% CI, 3.3%-4.3%)], ages 75-84 [CCI 0 = 3.7% (95% CI, 3.5%-3.9%) vs. CCI ≥ 2 = 3.4% (95% CI, 2.8%-4.0%)], and ages ≥85 [CCI 0 = 2.7%, (95% CI, 2.3%-3.2%) vs. CCI ≥ 2 = 2.5% (95% CI, 1.4%-3.6%)]. Cumulative risk of non-breast cancer mortality significantly increased with increasing CCI and age for women ages 65-74 [CCI 0 = 11% (95% CI, 10%-11%] vs. CCI ≥ 2 = 45% (95% CI, [43%-46%)], ages 75-84 [CCI 0 = 29% (95% CI, 29%-30%) vs. CCI ≥2 = 62% (95% CI, 60%-63%)], and ages ≥85 [CCI 0 = 59%, (95% CI, 57%-60%) vs. CCI ≥2 = 84% (95% CI, 81%-86%)]. Conclusion: Risk of non-breast cancer mortality was high and significantly increased with rising comorbidity burden and age whereas breast cancer risk was low and non-significantly decreased with both. These results suggest that women with a CCI score of ≥2 or ages ≥75 years may experience minimal benefit from continuing routine screening mammography. Future research is needed to delineate the specific benefits and harms of screening mammography in subsets of older women defined by age and comorbidity burden. [ABSTRACT FROM AUTHOR]

This study examined whether breast density is associated with risk of breast cancer in women age =65 years undergoing screening mammography in community practice. Methods: We used prospective cohort data between 1996 and 2012 from the Breast Cancer Surveillance Consortium (BCSC). We calculated separate cumulative incidence models for breast cancer incidence according to Breast Imaging Reporting and Data System (BI-RADS) breast density for women ages 65-74 and ages ≥75. Multivariable Cox proportional hazards regression models were fitted to determine the risk of invasive breast cancer adjusted for BCSC registry, race/ethnicity, BMI, hormone therapy use and benign breast disease. Results: Among the 403,268 women included in the study, approximately 40% were ages ≥75. The annual incidence rate of invasive breast cancer increased with increasing breast density among women ages 65-74 [BI- RADS fatty breasts: 2.2% (95% CI, 2.1%-2.4%) vs. heterogeneously or extremely dense breasts: 4.7% (95% CI, 4.6%-4.9%)] and women ages 75+ [BI-RADS fatty breasts: 2.3% (95% CI, 2.1%-2.5%) vs. heterogeneously or extremely dense: 4.3% (95% CI, 4.1%-4.5%)]. Women with BI-RADS fatty breasts had a decreased risk of breast cancer among women ages 65-74 [HR: 0.66 (95% CI: 0.58%-0.78%) and women ages ≥75 [HR: 0.73 (95% CI: 0.62%-0.87%). Women with BI-RADS heterogeneously or extremely dense breasts were found to have increased risk of breast cancer among women ages 65-74 [HR: 1.39 (95% CI: 1.28%-1.51%)] and women ages ≥75 [HR: 1.23 (95% CI: 1.10%-1.37%)]. Conclusions: Older women with higher BI-RADS density had a significantly increased risk of breast cancer. These findings add further evidence that breast density continues to be associated with an increased risk of breast cancer, even among women age ≥75 years. [ABSTRACT FROM AUTHOR]

The impact of the rise in breast cancer incidence associated with mammography diffusion on the prevalence of breast cancer family history is unknown, and may attenuate risk associations between family history and breast cancer. Methods: The proportions of women 40-74 years reporting a first-degree family history of breast cancer were estimated in the Breast Cancer Surveillance Consortium (BCSC, N = 1,170,900) from 1996-2012 and Collaborative Breast Cancer Study (CBCS; cases N = 23,400; controls N = 25,460) from 1987-2007. Breast cancer (ductal carcinoma in situ and invasive) relative risk estimates associated with family history and 95% confidence intervals (CI) were calculated using multivariable Cox proportional hazard (BCSC) and logistic regression (CBCS) models. Results: The proportion of women reporting a family history increased from 11% in the 1980s to 16% in 2010-13. Family history was associated with a 60% increased risk of breast cancer in the BCSC (hazard ratio = 1.61, 95% CI = 1.55-1.66) and CBCS (odds ratio = 1.66, 95% CI = 1.58-1.74), with relative risks decreasing with age. Trends in relative risks were not evident over time or stage of disease at diagnosis, except among older women (60-74) where estimates were attenuated in more recent years (P-trend = 0.08 for both cohorts). Conclusion: The proportion of women with a first-degree family history of breast cancer increased over time and by age, nonetheless breast cancer risk associations with family history were constant over time for women 40-59. First-degree family history of breast cancer remains an important breast cancer risk factor, especially for younger women, despite its increasing prevalence in the mammography screening era. [ABSTRACT FROM AUTHOR]