PURPOSE: We assessed the associations between the 21-gene recurrence score assay (RS) receipt, subsequent chemotherapy use, and medical expenditures among @entity1 with @entity0 . @entity1 AND METHODS: Data from the @entity5 Registry were used to assemble a retrospective cohort of @entity1 with @entity0 from 2007 to 2010 who underwent initial surgical treatment. These data were merged with administrative claims from the 12-month periods before and after diagnosis to identify comorbidities, treatments, and expenditures (n = 7,287). Propensity score-weighted regression models were estimated to identify the effects of RS receipt on chemotherapy use and medical spending in the year after diagnosis. RESULTS: The associations between RS receipt and outcomes varied markedly by @entity1 age. RS use was associated with lower chemotherapy use among @entity1 younger than 55 (19.2% lower; 95% CI, 10.6 to 27.9). RS use was associated with higher chemotherapy use among @entity1 75 to 84 years old (5.7% higher; 95% CI, 0.4 to 11.0). RS receipt was associated with lower adjusted 1-year medical spending among @entity1 younger than 55 ( 15,333 lower; 95% CI,  2,841 to  27,824) and with higher spending among @entity1 who were 75 to 84 years old ( 3,489 higher; 95% CI,  857 to  6,122). CONCLUSION: RS receipt was associated with reduced use of adjuvant chemotherapy and lower health care spending among @entity1 with @entity0 who were younger than 55. Conversely, among @entity1 75 and older, RS testing was associated with a modest increase in chemotherapy use and slightly higher spending. From a population perspective, the impact of RS testing on @entity0 treatment and health care costs is much greater in younger @entity1 .

Adjuvant Chemotherapy Use and Health Care Costs After Introduction of Genomic Testing in XXXX .

@entity1 :: ('9606', 'Species') :: ['women', 'patients', 'patient', 'PATIENTS'] @entity5 :: ('MESH:D009369', 'Disease') :: ['Pennsylvania Cancer'] @entity0 :: ('MESH:D001943', 'Disease') :: ['breast cancer', 'early-stage breast cancer']
@entity0 :: (MESH:D001943,Disease) :: ['Breast Cancer']
