Mammography interval and breast cancer mortality in women over the age of 75

Abstract

Purpose To evaluate the relationship between mammography interval and breast cancer mortality among older women with breast cancer. Methods The study population included 1,914 women diagnosed with invasive breast cancer at age 75 or later during their participation in the Women’s Health Initiative, with an average follow-up of 4.4 years (3.1 SD). Cause of death was based on medical record review. Mammography interval was defined as the time between the last self-reported mammogram 7 or more months prior to diagnosis, and the date of diagnosis. Multivariable adjusted hazards ratios (HR) and 95% confidence intervals (CIs) for breast cancer mortality and all-cause mortality were computed from Cox proportional hazards analyses. Results Prior mammograms were reported by 73.0 % of women from 7 months to ≤ 2 year of diagnosis (referent group), 19.4% (> 2 – < 5 years), and 7.5% (≥5 years or no prior mammogram). Women with the longest vs. shortest intervals, had more poorly differentiated (28.5% vs. 22.7%), advanced stage (25.7% vs. 22.9%) and estrogen receptor negative tumors (20.9% vs. 13.1%). Compared to the referent group, women with intervals of > 2 – < 5 years or ≥ 5 years had an increased risk of breast cancer mortality (hazard ratio (HR) 1.62, 95% confidence interval (CI) 1.03–2.54) and (HR 2.80, 95% CI, 1.57–5.00) respectively, p trend = 0.0002. There was no significant relationship between mammography interval and other causes of death. Conclusions These results suggest a continued role for screening mammography among women 75 years of age and older.

Cardiovascular disease and mortality after breast cancer in postmenopausal women: Results from the Women’s Health Initiative

“…In the WHI, mammographic examinations were required annually for women in the hormone therapy arm of the trial, every other year for those in the dietary modification arm, but were not required for participants in the WHI-OS. There are no clinical guidelines and trials specifically focusing on breast cancer screening among older women [ 43 , 44 ]. An evaluation of time between last mammography screening and breast cancer diagnosis in the WHI among women age 75+ at time of diagnosis suggested a benefit of more recent screening based on reduced deaths due to breast cancer [ 43 ] but not reduction in deaths to other causes.…”

“…There are no clinical guidelines and trials specifically focusing on breast cancer screening among older women [ 43 , 44 ]. An evaluation of time between last mammography screening and breast cancer diagnosis in the WHI among women age 75+ at time of diagnosis suggested a benefit of more recent screening based on reduced deaths due to breast cancer [ 43 ] but not reduction in deaths to other causes. There is also little evidence of the benefits of drug therapies or nonpharmacological approaches, such as exercise or nutrition, in reducing total or CVD morbidity and mortality in the 70+ age groups with localized, lymph node-negative breast cancer, a growing phenotype of breast cancer with the aging population [ 27 , 29 , 45 ].…”

Is the false-positive rate in mammography in North America too high?

“…These findings themselves indicate that at least a proportion of screen-detected cancers will progress to the extent of clinical detection within the lifetimes of older females. Furthermore, clinically detected cancers are generally found at a later stage than screen-detected cancers 140,141 and the stage at which invasive cancer is detected in patients older than 70 years proved to be greatly influential upon mortality risk. 140 Simon et al 141 determined that the breast cancer mortality risk related to advancement of cancer in this age group can be limited by screening at an interval protracted over a period no longer than every 2 years.…”

“…Furthermore, clinically detected cancers are generally found at a later stage than screen-detected cancers 140,141 and the stage at which invasive cancer is detected in patients older than 70 years proved to be greatly influential upon mortality risk. 140 Simon et al 141 determined that the breast cancer mortality risk related to advancement of cancer in this age group can be limited by screening at an interval protracted over a period no longer than every 2 years. These results collectively indicate continued utility for screening on a biennial schedule for females over 70 years.…”

Mammography: an update of the EUSOBI recommendations on information for women

“…A general suggestion is to continue screening with mammography for elderly women as long as their health is not significantly compromised by illness that drastically reduces life expectancy [41, 42]. Discuss this decision with your radiologist.…”