Routine Pre-Treatment MRI for Breast Cancer in a Single-Payer Medical Center: Effects on Surgical Choices, Timing and Outcomes

Abstract

Introduction: Pre-operative MRI is being used with increasing frequency to evaluate breast cancer patients, but the debate surrounding risks and benefits of this use continues. At our institution, we instituted a standardized protocol for pre-operative MRI. Here, we compare patients seen prior to routine use of MRI to those seen after and examine effects on surgical choices, timing and outcomes.Methods: This is a retrospective review of a prospectively collected database of all new invasive breast cancers seen from January 2007 to December 2012. The control group (CG) did not receive MRI, while the MRI group (MRG) underwent MRI according to our pretreatment protocol. Groups were compared with regards to basic demographics, initial surgical choices, need for re-excision, and surgical timing. The electronic medical records of patients in the MRG who underwent mastectomy as their initial surgery were examined closely to determine the main factors leading to their choice of surgery. Finally, correlation between findings on MRI and final surgical pathology was analyzed.Results: Of 282 patients included, 38 were in the CG and 244 in the MRG; the groups were well matched. The MRG had a significantly higher percentage of patients choosing initial mastectomy (MRG: 47.1% vs CG 21.1%, p=0.003). Patients seen in the first 2 years of the study were less likely to choose mastectomy than those enrolled in the latter years (29.2%vs 48.6%, p=0.004). The MRG had a lower chance of return to the operating room for re-excision (15.2% vs 28.9%, p=0.035). The average time from initial imaging to initial surgery was approximately the same between groups (MRG: 39.7 days vs CG 42.1 days, p=0.45) and the MRG actually had shorter time to definitive (margin-negative) surgical management (MRG: 43.5 days vs CG: 50.3 days, p=0.079). One hundred-fifteen patients in the MRG underwent mastectomy as initial surgery. Of these, 64 (55.7%) had no additional findings on MRI and chose mastectomy based on patient preference; 30 patients (26.1%) (29 unilateral, 1 bilateral) had mastectomy because of MRI findings. Of the 31 breasts removed (29 unilateral and 1 bilateral mastectomies) because of MRI findings, 26 (83.9%) had histologic findings that correlated with the MRI findings, while 5 (16.1%) did not.Conclusion: Patients receiving routine pre-treatment MRI had an increased mastectomy rate, but had a lower re-excision rate. We found no delay to initial surgical therapy and, perhaps more importantly, a slight decrease in time to margin-negative surgical therapy in the MRI group. Women choosing mastectomy after MRI did so because of personal preference over half of the time, while MRI findings influenced this choice in 26% of these women. When MRI findings did lead to mastectomy, these findings were confirmed by pathology results in the vast majority of cases.

Preoperative imaging for breast conservation surgery—do we need more than conventional imaging for local disease assessment?

“…However, in a separate study, Vreeland et al (26) found no delay to initial surgical therapy and, perhaps more importantly, a slight decrease in time to margin-negative surgical therapy in the MRI group.…”

Utilization of breast MRI and breast MRI-guided biopsy in clinical practice: results of a survey in Québec and France

“…An audit from 2013 performed at the Centre Hospitalier de l'Université de Montréal showed that among 687 pending breast MRI requests identified at the end of September, 67% exceeded recommended wait times, with 10% exceeding them by more than 12 months [3]. The impact of preoperative MRI on surgical waiting time has been explored through several recent publications [5,24,[26][27][28], with all of them, except Vreeland et al (who does not use time of initial surgery but time of margin-negative surgery as end-point), suggesting that the time from diagnosis to operative treatment of breast cancer has increased over the years, particularly with the advent of breast MRI [5,[26][27][28][29]. Although we did not evaluate the impact of preoperative breast MRI on surgical waiting time in our study, our results indicate that breast MRI exams are usually performed within a reasonable time frame following their initial request.…”

Recent Progress for the Techniques of MRI-Guided Breast Interventions and their applications on Surgical Strategy

“…MRI can give significant additional advice that single or multicentric diseases may not be visible or be detected with traditional breast lesion screening equipment, with a precise determination of the extent of the disease (Figure 1). A retrospective review showed that routine pretreatment MRI was not associated with delay in care, with initial surgery occurring in approximately the same interval after diagnosis, and margin-negative surgery actually being accomplished more quickly in patients receiving MRI [17]. Examples of MRI-detected single right breast lesion of a 47-year-old woman (white horizontal arrow), which is invisible on the corresponding ultrasound and mammography, and the radiologist's report shows BI-RADS 4.…”