Predictors of advanced imaging use during breast cancer surveillance.

Abstract

e18337 Background: Our objectives were to determine advanced imaging use (whole body imaging with bone scan, CT, or PET-CT and breast MRI) during breast cancer surveillance, and to identify drivers of potential imaging overuse as outlined by ASCO’s Choosing Wisely initiative. Methods: Cancer registry records for 2923 women diagnosed with primary breast cancer in Washington State from January 1, 2007 to December 31, 2014 were linked with claims data from two regional commercial insurance plans. Inclusion criteria included women with AJCC stage 0-3 disease treated with curative intent. Women without continuous insurance enrollment from 3 months prior to diagnosis until 14 months after diagnosis were excluded. Surveillance began 4 months after the end of primary therapy and lasted for 15 months or until restart of treatment. Women’s (age, race, family history) and tumor (grade, receptor status, stage) characteristics were collected. Evaluation and management codes from claims data were used to determine mammography, advanced imaging, and tumor biomarker use during the peri-diagnostic and surveillance periods. Multivariate logistic regression models were used to identify factors associated with advanced imaging use during surveillance. Results: Of eligible women, 80.0% (2332/2923) received mammography, 16.5% (483/2932) received whole body imaging, and 21.5% (670/2932) received breast MRI during the surveillance period. Whole body imaging was significantly associated with increasing stage of disease (stage 3: OR = 3.39, 95% CI: 2.30-5.02), peri-diagnostic whole body imaging (OR = 1.80, 95% CI: 1.36-2.38), and surveillance tumor biomarker use (OR = 1.83, 95% CI: 1.46-2.31). Significant predictors of surveillance breast MRI included young age ( < 45 years: OR = 2.40, 95% CI:1.78- 3.25), family history (OR = 1.58, 95% CI:1.26-1.98), peri-diagnostic breast MRI (OR = 2.01, 95% CI: 1.56-2.59), and surveillance tumor biomarker use (OR = 1.74, 95% CI:1.41-2.17). Conclusions: Peri-diagnostic use of advanced imaging and surveillance use of tumor biomarkers are associated with advanced imaging use during surveillance, and may represent targets for interventions to increase adherence to Choosing Wisely clinical guidelines.