Increasing Use of Preoperative Breast MRI Linked to Increased Postdiagnostic Imaging and Biopsy, Mastectomy, and Surgery Delay
In a Canadian population-based study reported in JAMA Oncology, Arnaout et al found that breast magnetic resonance imaging (MRI) is increasingly used in preoperative evaluation of women with breast cancer and that its use is associated with increased likelihood of confirmatory breast imaging, breast biopsy, imaging to assess for distant metastasis, mastectomy, contralateral prophylactic mastectomy, and longer delay to surgery. As noted by the investigators: “While existing literature has found little benefit to MRI in most patients, potential downstream consequences associated with breast MRI [have not been] well described.”
Increasing Use
The retrospective cohort study included data on 53,015 patients with primary operable breast cancer treated from 2003 to 2012 obtained from administrative heath care databases in Ontario.
Overall, 14.8% of patients (n =7,824) had a preoperative MRI. During the 10-year study period, MRI use increased eightfold across all stages of breast cancer (from 3% to 24%, P < .001 for trend).
Factors Associated With MRI
On multivariate analysis adjusting for patient-, disease-, health system–, and clinician-related covariates, factors significantly associated (all P < .001) with MRI use were younger age (odds ratios [ORs] = 0.68 to 0.07 for 10-year groups of ≥ 40 years vs < 40 years), higher socioeconomic status (ORs = 1.05–1.48 for second to highest quintile vs first quintile), higher Charlson comorbidity score (ORs = 1.16 and 1.17 for 1–2 and ≥ 3 vs 0), higher disease stage (ORs = 1.19 and 1.15 for II and III vs I), lobular histology (OR = 2.85 vs ductal), later year of diagnosis ORs = 1.65 to 12.78 for 2005 to 2012 vs 2004), surgery performed in a teaching hospital (OR = 2.85 vs community hospital), surgeon volume of surgical procedures (eg, ORs = 1.23–1.50 for 161–270 to 453–964 vs 1–79), and fewer years of surgeon experience (eg, ORs = 0.76, 0.40, and 0.38 for 15–19, 26–33, and 34–61 vs 6–14 years).
Additional Procedures and Surgery Delay
On multivariate analysis, use of preoperative breast MRI was associated with increased likelihood of: postdiagnosis confirmatory breast imaging (OR = 2.09, 95% confidence interval [CI] = 1.92–2.28), postdiagnosis breast needle biopsies (OR = 1.74, 95% CI = 1.57–1.93), postdiagnosis imaging to assess for distant metastasis (OR = 1.51, 95% CI = 1.42–1.61), mastectomy (OR = 1.73, 95% CI = 1.62–1.85), contralateral prophylactic mastectomy (OR = 1.48, 95% CI = 1.23–1.77), and > 30-day wait to surgery (OR = 2.52, 95% CI = 2.36–2.70). The mean number of days to surgery was 12 days greater in patients receiving preoperative MRI (P < .001).
The investigators concluded; “Preoperative breast MRI use has increased substantially in routine clinical practice and is associated with a significant increase in ancillary investigations, wait time to surgery, mastectomies, and contralateral prophylactic mastectomies.”
Angel Arnaout, MD, of Ottawa Hospital Research Institute, University of Ottawa, is the corresponding author for the JAMA Oncology article.
The study was supported by a 2013 University of Ottawa, Department of Medicine, Patient Safety Grant.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
