Abstract
PURPOSE: Preoperative magnetic resonance imaging (MRI) after breast cancer diagnosis is increasingly used to improve locoregional staging, particularly among women with dense breasts, extensive ductal carcinoma in situ, and lobular histology. The goals of this study were to (1) assess whether use of preoperative MRI varies by race and insurance type; and (2) determine whether preoperative MRI is associated with downstream surgical management. MATERIALS AND METHODS: We performed a retrospective cohort study of women with stage 0-III breast cancer who were treated with surgical resection within our academic health system (2016-2019). Patients were categorized by race and insurance type. The primary outcome was receipt of preoperative MRI. Secondary outcomes included surgery extent (lumpectomy v mastectomy) and receipt of a second operation. RESULTS: A total of 1,410 women (27% Black, 73% White; 67% private insurance, 26% Medicare, 6% Medicaid) were included. Black patients were significantly less likely to undergo preoperative MRI than White patients (odds ratio [OR], 0.54 [95% CI, 0.38 to 0.76]; P < .001). There was no association between insurance type and preoperative MRI (Medicare v private: OR, 0.77 [95% CI, 0.52 to 1.15]; P = .208; Medicaid v private: OR, 0.67 [95% CI, 0.36 to 1.25]; P = .210). White patients who underwent preoperative MRI were less likely to undergo lumpectomy versus those who did not (OR, 0.53 [95% CI, 0.37 to 0.76]; P < .001). Likelihood of re-excision was lower for Black women who had undergone MRI versus those who had not (OR, 0.43 [95% CI, 0.20 to 0.93]; P = .031). CONCLUSION: Black patients were less likely than White patients to undergo preoperative MRI, yet Black women who underwent MRI were less likely to require re-excision. Standardizing preoperative MRI use may mitigate provider- and system-level biases and promote more equitable care.