Mammography use may partially mediate disparities in tumor size at diagnosis in women with social security disabilities

Objective: This study determined the association between screening mammography and tumor size at diagnosis in older women whose original reason for entitlement to Medicare benefits was disability (SSDI). Methods: A retrospective study of female Medicare beneficiaries older than 69 years diagnosed with breast cancer using Surveillance Epidemiological End Results (SEER)-Medicare linked database. Multiple linear regression techniques were used to determine the effect of screening mammography use on tumor size. Main Findings: The total number of women was 413 with SSDI and 8,989 without. Bivariate analysis showed that significantly fewer women with SSDI used screening mammography (45% vs. 38%, P = 0.0006) during the two years prior to diagnosis. Mean tumor size at diagnosis was 2.91 mm (95%, CI = 1.10, 4.73) larger in the group with SSDI. Conclusion: This study found that older women whose original reason for Medicare benefits was disability present with larger tumors at breast cancer diagnosis compared to those who were not. Screening mammography may partially mediate the disparity.