Screening mammography outcomes: risk of breast cancer and mortality by comorbidity score and age

Abstract

BACKGROUND

Potential benefits of screening mammography among women ages ≥75 remain unclear.

METHODS

We evaluated 10-year cumulative incidence of breast cancer and death from breast cancer and other causes by Charlson Comorbidity Index (CCI) and age in the Medicare-linked Breast Cancer Surveillance Consortium (BCSC, 1999-2010) cohort of 222,088 women with ≥1 screening mammogram between ages 66 and 94.

RESULTS

During median follow-up of 107 months, 7,583 were diagnosed with invasive breast cancer and 1,742 with ductal carcinoma in situ (DCIS); 471 died from breast cancer and 42,229 from other causes. The 10-year cumulative incidence of invasive breast cancer did not change with increasing CCI but decreased slightly with age: ages 66-74 [CCI0=4.0% (95%CI 3.9-4.2%) vs. CCI≥2=3.9% (95%CI, 3.5-4.3%)], ages 75-84 [CCI0=3.7% (95%CI, 3.5-3.9%) vs. CCI≥2=3.4% (95%CI, 2.9-3.9%)], and ages 85-94 [CCI0=2.7%, (95%CI, 2.3-3.1%) vs. CCI≥2=2.1% (95%CI, 1.3-3.0%)]. The 10-year cumulative incidence of other cause death increased with increasing CCI and age: ages 66-74 [CCI0=10.4% (95%CI, 10.3-10.7%) vs. CCI≥2=43.4% (95%CI 42.2-44.4%)], ages 75-84 [CCI0=29.8% (95%CI, 29.3-30.2%) vs. CCI≥2=61.7% (95%CI, 60.2-63.3%)], and ages 85-94 [CCI0=60.3%, (95%CI, 59.1-61.5%) vs. CCI≥2=84.8% (95%CI, 82.5-86.9%)]. The 10-year cumulative incidence of breast cancer death was small and did not vary by age: ages 66-74=0.2% (95%CI: 0.2-0.3%), ages 75-84=0.29% (95%CI: 0.25%-0.34%) and ages 85-94=0.3% (95%CI: 0.2-0.4%).

CONCLUSIONS

Cumulative incidence of other cause death was many times higher than breast cancer incidence and death, depending on comorbidity and age. Hence, older women with increased comorbidity may experience diminished benefit from continued screening.

To read more, see the following article on the PubMed website: PMID: 31593591