Abstract B97: Potential missed opportunities for early detection with screening mammography: Does the quality of radiologist's interpretation vary by patient socioeconomic advantage/disadvantage?

Introduction: Non-Hispanic (nH) Black and Hispanic women are more likely than their nH White counterparts to be diagnosed at a later stage of breast cancer. Potential explanations for this stage disparity include racial/ethnic differences in biological aggressiveness of breast cancer, differences in utilization of screening, and differences in the quality of the screening process. The purpose of these analyses was to examine whether quality of mammography interpretation as performed by the original reading radiologist varied by patient sociodemographic characteristics. We hypothesized that the proportion of potentially missed cancers at original interpretation would be greater in more disadvantaged patient groups (nH Black and Hispanic patients, lacking private health insurance, with lower income and education), such that it might contribute to disparities in stage at diagnosis. Methods: The “Breast Cancer Care in Chicago” study included 989 recently diagnosed nH Black, Hispanic and nH White breast cancer patients residing in Chicago and diagnosed in 2005–2008. Patients reporting either initial awareness of their breast cancer through screening mammography or initial awareness through symptoms despite a prior mammogram within 2 years of detection were eligible for this substudy (N=597). Of these, 369 (62%) consented to a review of their mammogram and other breast images involved in their screening and diagnosis. Original mammograms and diagnostic follow-up images and corresponding reports were requested from screening and diagnostic facilities. Often, multiple facilities were involved for a single patient. For 185 patients, we were able to obtain the original index mammogram (that detected the breast cancer) and the original prior mammogram (that did not detect the cancer), and these 185 patients are the subject of these analyses. A single breast imaging specialist (EC) performed a blinded review of the prior mammogram (blinded to the original interpretation and all other subsequent screening and diagnostic images and results), followed by an unblinded review of the index mammogram (mammogram at time of diagnosis). All reviews were blinded to patient age, race/ethnicity and other sociodemographic characteristics. If an actionable lesion (BIRADs category 0, 4 or 5) on the prior film was found in the same breast and quadrant as the cancer seen on the index mammogram, it was considered a potentially detectable lesion. Results: Of 185 prior mammograms read as non-malignant by the original radiologist, 44% (N=82) had a potentially detectable lesion. The probability of a potentially detectable lesion was greater among patients lacking health insurance or with public but no private insurance, compared to those with private insurance (63% vs. 39%, respectively, p=0.005). The probability of a potentially detectable lesion was also greater for patients reporting annual household incomes below $30,000 compared to higher income patients (59% vs. 37%, respectively p=0.006) as well as minority compared to nH White patients (52% vs. 38%, p=0.04). Similar though insignificant trends were seen for lower vs. greater education. Conclusions: Disadvantaged socioeconomic status appears to be associated with lower quality mammography interpretation for malignancy, and may be contributing to racial/ethnic disparities in breast cancer stage at diagnosis. Citation Information: Cancer Epidemiol Biomarkers Prev 2011;20(10 Suppl):B97.