Do Early Screening Mammography Outcomes <Age 40 Adversely Impact the Timing of Screening Mammography >40 Differentially by Race?

Purpose: Previous studies suggest 29% of women ages 30-39 report having had a mammogram; this varies by race/ethnicity. Black women have a greater odds than White women of reporting multiple mammograms <40; yet ≥40, Black and Asian women are less likely to receive adequate mammography screening. Could early mammography testing adversely impact future mammography use? Our objective is to determine whether racial/ethnic differences and the outcome of a first mammogram <40 (false positive (FP) or true negative (TN)) may delay the age of the first mammogram ≥40.

Methods: Data were pooled from seven mammography registries of the National Cancer Institute's Breast Cancer Surveillance Consortium (BCSC), a network created to study performance and outcomes in community practice. Using 1996-2006 data, we identified 29,158 women with a screening mammogram between ages 40-45 who also underwent screening mammography for the first time ever at an age <40 in the BCSC data. We used logistic regression to examine the association between race/ethnicity and first mammography outcomes on the odds of delayed mammography after 40 (ages 43-45 compared to 40-42).

Results: Overall, 96% of these women's first screens <40 were at ages 35 or later, and 93% of their first screens >40 were at ages 40-42. Regression models adjusted for age at first screen suggest: (1) Hispanic women have an increased odds of waiting to screen until 43-45 compared to White women, regardless of first screening outcome <40; (2) White and Black women whose first screen <40 was a FP have less odds of delaying future screening than those with a TN; and (3) among women with a TN, Black women have an increased odds of waiting to screen until 43-45 relative to White women, with no observed difference between Asian and White women.

Conclusions: Findings suggest a differential impact of early mammography outcomes on future mammography use by race/ethnicity, among the women in our sample with a known first screening mammogram before and after age 40. The concern for harmful effects of over-screening young women drives the need for additional work in this area.