Tumor characteristics associated with tomosynthesis versus digital mammography in older women with screen-detected breast cancer
摘要
Digital breast tomosynthesis (DBT) has demonstrated improved cancer detection compared with digital mammography (DM) in trials of women aged 50–74, identifying more invasive cancers and detecting tumors at smaller sizes. However, its benefits for women over the age of 75 have not been examined.
PurposeTo assess whether DBT versus DM is associated with favorable tumor characteristics and detection of less conspicuous histologic subtypes in women aged ≥ 75 compared with those aged 67–74, thereby informing screening strategies and overdiagnosis risks.
MethodsWe conducted a SEER-Medicare retrospective cohort study of women aged ≥ 67 diagnosed with screen-detected ER+/HER2- breast cancer from 2015 to 2021. The primary exposure was screening modality (DBT vs. DM). Outcomes included tumor size, nodal involvement, grade, and histology (invasive lobular carcinoma [ILC] vs. other). Multivariable logistic regression was used to assess the association between screening modality and tumor characteristics among women aged 67–74 and ≥ 75.
ResultsAmong 17,201 women with screen-detected breast cancer, 43.6% were ≥ 75 at diagnosis and 60.4% were detected by DBT. In women aged 67–74, DBT was associated with higher odds of smaller tumors (adjusted odds ratio [aOR] = 1.18, 95% confidence interval [CI] = 1.08–1.29), grade I vs. II or III disease (aOR = 1.14, CI = 1.04–1.26), node-negative disease (aOR = 1.15, CI = 1.00-1.31, P = 0.048), and ILC histology (aOR = 1.29, CI = 1.13–1.48). In contrast, among women aged ≥ 75, DBT remained associated with higher odds of grade I tumors (aOR = 1.21, CI = 1.08–1.35) and node-negative disease (aOR = 1.18, CI = 1.00-1.39, P = 0.049), but was not significantly associated with smaller tumor size (aOR = 0.99, CI = 0.90–1.10) or ILC histology (aOR = 1.13, CI = 0.98–1.32).
ConclusionsDBT was associated with lower grade and node negative disease in women ≥ 75, but not with smaller tumor size or ILC histology. The incremental advantage of DBT over DM may diminish with age, making the two modalities more comparable in women ≥ 75.