Abstract 1891
Background
Randomized clinical trials (RCTs) have shown that initiating breast cancer (BC) screening between ages 50 to 69 and continuing it for 10 years decreases BC mortality. None of the existing RCTs included women over 74 and all included few women aged 70-74, such that the 95% confidence interval (CI) ranged from preventing 32.1 deaths to causing 17.2 deaths. However, there is no RCT data on when a woman should stop receiving BC screening, yet an estimated 52% of women over 75 receive screening mammograms in the US. A future randomized trial to study when to stop screening may be infeasible and potentially unethical. We used insurance claims data to emulate a (hypothetical) target trial of the effect of continuing screening on BC mortality among Medicare beneficiaries aged 70-74 or 75-84 years.
Methods
We emulated a hypothetical trial using a population-based cohort study with 20% random sample of Medicare (1999-2008). We selected 1,058,013 Medicare beneficiaries aged 70 to 84 with a life expectancy of at least 10 years and no previous diagnosis of BC, and who received a BC screening. We compared the following two strategies: continuing annual screening vs. stopping screening mammograms. The main outcome was 8-year standardized risk of BC mortality by age group (70-74, 75-84). Estimates are standardized by baseline and time-varying variables.
Results
In the 70-74 age group, the estimated 8-year BC-specific death risk difference (95% CI) of continuing vs. stopping screening was -1.0 deaths per 1000 women (-2.3 to 0.1); hazard ratio 0.78 (0.63 to 0.95). In the 75-84 age group, the corresponding risk difference was 0.07 deaths per 1000 women (-0.93 to 1.3); hazard ratio 1.00 (0.83 to 1.19). The estimated 8-year risk of BC was 5.5% under the continue screening strategy (5.3% in the 70-74 age group, 5.8% in the 75-84 age group), and 3.9% under the stop screening strategy (3.9% in the 70-74 age group, 3.9% in the 75-84 age group).
Conclusions
Among women who have received at least one screening mammogram, we estimated that, compared with stopping BC screening, continuing screening past the age of 75 years results in no material difference in cancer-specific mortality over the following 8-year period. Our results in the age range of 70-74 match those of existing randomized clinical trials.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
US National Institutes of Health.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
2115 - Preclinical in vivo screening to predict responder patients depend on EGFR status
Presenter: Yejin Kim
Session: Poster Display session 3
Resources:
Abstract
3349 - Interplay between miR-17-5p and MALAT-1 Shapes The Cytokine Storm in Triple Negative Breast Cancer (TNBC) Tumor Microenvironment
Presenter: Raghda Soliman
Session: Poster Display session 3
Resources:
Abstract
4014 - Clinical verification on the relationship between lipid metabolism and the immune microenvironment of breast cancer
Presenter: Wataru Goto
Session: Poster Display session 3
Resources:
Abstract
4158 - The clinical and transcriptional signatures of human CD204 reveal an applicable marker for tumor associated macrophage in breast cancer
Presenter: Yunjie He
Session: Poster Display session 3
Resources:
Abstract
5392 - Activated effector T cells co-expressing multiple inhibitory receptors (IRs) are enriched in the tumor immune microenvironment in high grade serous ovarian cancer (HGSOC)
Presenter: Alice Bergamini
Session: Poster Display session 3
Resources:
Abstract
2617 - Oncolytic reovirus as a new anti-tumor strategy in castration resistant prostate cancer
Presenter: Yunlim Kim
Session: Poster Display session 3
Resources:
Abstract
2995 - Dysregulation of helper T lymphocytes in esophageal squamous cell carcinoma (ESCC) patients is highly associated with aberrant production of miR-21
Presenter: Ali Memarian
Session: Poster Display session 3
Resources:
Abstract
3597 - Myeloid derived suppressor cells but not regulatory T cells are associated with adaptive immunity and clinical outcomes in anal squamous cell carcinoma
Presenter: Christophe Borg
Session: Poster Display session 3
Resources:
Abstract
3430 - Evaluation of immune responses among responders (R) and non-responders (non-R) in a humanized mouse model with colorectal cancer (CRC) xenografts treated with combination immunotherapy
Presenter: Juan Marín Jiménez
Session: Poster Display session 3
Resources:
Abstract
1995 - ¬¬Advanced melanoma patients with high CD16+ macrophages have better response and survival to anti-PD-1 based immunotherapy
Presenter: Hansol Lee
Session: Poster Display session 3
Resources:
Abstract