Preoperative Breast MRI and Surgical Outcomes in Local Ductal Carcinoma in Situ
Posted: Friday, May 10, 2019
According to the findings of the randomized phase III IRCIS trial, published in the Journal of Clinical Oncology, including breast magnetic resonance imaging (MRI) in standard imaging evaluation prior to breast-conserving surgery for women with ductal carcinoma in situ (DCIS) did not result in a significant benefit. However, the investigators noted, this imaging strategy may be reconsidered in the future if new MRI sequences are improved.
“The study did not show sufficient surgical improvement with the use of preoperative MRI to be clinically relevant in DCIS staging,” concluded Corinne Balleyguier, MD, PhD, of the Centre Léon Bérard in France, and colleagues.
The trial included 352 women with biopsy-proven DCIS and a cluster or a mass smaller than 30 mm who were determined to be analyzable. Participants were randomly assigned to receive either a standard imaging preoperative evaluation (n = 174) or one that included breast MRI (n = 178).
Of these patients, 345 had an assessable endpoint, with 35 of 173 patients (20%) in the MRI arm and 47 of 172 (27%) in the standard arm undergoing reoperation for positive or close margins within 6 months of initial surgery. Although the absolute difference was 7%, resulting in a relative reduction of 26% (stratified odds ratio = 0.68; P = .13), the difference when considering the population with an assessable endpoint alone was 9% (stratified odds ratio = 0.59; P = .05).
In total, 31 of 176 women (18%) in the MRI arm and 30 of 173 patients (17%) in the standard arm underwent a mastectomy (stratified P = .93). Of 100 lesions analyzed using MRI, nonmass-like enhancement (82%) was more common than mass enhancement (20%).
Disclosure: The study authors’ disclosure information may be found at ascopubs.org.
