Women with triple-negative breast cancer who undergo preoperative MRI before breast-conserving surgery have lower rates of disease recurrence and reexcision, according to a study published March 18 in the Annals of Surgical Oncology.
The findings are good news for women dealing with this particular type of aggressive cancer, wrote a team led by Dr. Laura Burkbauer, who was at the University of Pennsylvania in Philadelphia at the time of the study and is now at University of North Carolina in Chapel Hill.
"Preoperative MRI has not been found to improve surgical outcomes in patients undergoing breast-conserving surgery," the group wrote in a statement it shared with AuntMinnie.com. "However, previous studies have not examined the utility of preoperative MRI in patients with aggressive tumor subtypes such as triple-negative breast cancer, and there is some suggestion that MRI may improve local control in these patients."
Some consider breast MRI to be the modality with the highest sensitivity for identifying breast cancer, performing better than mammography or ultrasound -- a particular benefit for women with triple-negative breast cancer, which mammography can miss. In fact, compared with receptor-positive breast cancers, "mammography is less effective at detecting triple-negative breast cancer, with 9% to 18% showing no mammographic evidence of disease," the group wrote.
And women with triple-negative breast cancer have local recurrence rates of 8.8% (median follow-up, 61 months) -- seven times higher than the rate for hormone receptor-positive breast cancers.
"There is reason to think that patients with triple-negative breast cancer, in particular, may benefit from use of preoperative MRI," Burkbauer and colleagues explained.
The team conducted a study that included 648 women with triple-negative breast cancer who had breast-conserving surgery between 2009 and 2018. It then compared demographic and clinical characteristics between women who had preoperative MRI (292, or 45.1%) and those who did not (356, or 54.9%).
Both local recurrence and re-excision rates were lower in the cohort of women who had preoperative MRI compared with those who did not undergo MRI before surgery.
| Recurrence and re-excision rates in women with triple-negative breast cancer depending on preoperative MRI | ||
| Measure | No preoperative MRI | Preoperative MRI |
| Local recurrence rate | 21.6% | 3.4% |
| Reexcision rate | 27.2% | 3.7% |
The study results are promising. Yet questions persist regarding the utility of preoperative MRI in patients with aggressive cancers, such as triple-negative breast cancer, and include the following, according to Burkbauer's team:
- Is preoperative MRI better at tumor staging and selecting patients for breast-conserving surgery versus mastectomy compared to conventional breast imaging?
- Is there a role for preoperative abbreviated-MRI?
- How can reexcision rates be further reduced in breast-conserving surgery?
These questions are being explored by the Alliance A11104 Clinical Trial from the American College of Radiology Imaging Network (ACRIN), the authors reported.
How these findings -- as well as those from the Alliance trial -- will influence clinical practice remains to be seen, they wrote.
"Our data demonstrated that re-excision rates are affected by myriad factors, including surgeon-specific variables which may not routinely be captured in databases," Burkbauer and colleagues concluded. "Such data may add nuance to result interpretation in prior and future studies."
