Could Brain MRI Screening be Beneficial for Patients with Inflammatory Breast Cancer?

Noting a high incidence of central nervous system metastasis (mCNS) in patients with stage III and stage IV inflammatory breast cancer (IBC), the authors of a new study suggest that surveillance screening with brain magnetic resonance imaging (MRI) may be beneficial in this patient population.

In the retrospective study, recently published in Cancer, researchers reviewed data from 372 patients who had stage III inflammatory breast cancer (IBC) and 159 patients with de novo stage IV IBC. Among patients with stage III IBC, the study authors noted a 9 percent two-year incidence and an 18 percent five-year incidence of mCNS. For patients with de novo stage IV IBC, there was a 30 percent incidence of mCNS at two years and a 42 percent incidence at five years, according to the researchers.¹

The study authors suggested that the incidence of mCNS in patients with IBC may be even higher when one takes asymptomatic manifestations into account.

“Because most patients in this study were diagnosed with mCNS in the context of neurologic symptoms, it is likely that the true incidence of mCNS in patients with IBC is even higher than reported in our study because some patients likely have undetected, asymptomatic mCNS,” wrote lead study author Laura E.G. Warren, M.D., EdM, who is affiliated with the Department of Radiation Oncology at the Dana-Farber Cancer Institute in Boston, and colleagues.

Despite research showing that the omission of whole brain radiotherapy (WBRT) does not affect mortality rates in patients with limited intracranial metastases, Warren and colleagues noted that nearly half of patients in the last five years of their study were treated with WBRT.^1-3 While acknowledging this may have been necessary to address a larger extent of intracranial metastases, the study authors maintained that WBRT does have short- and long-term neurocognitive side effects. Accordingly, the use of brain MRI monitoring may aid in determining the presence or extent of intracranial metastases, enabling earlier and more targeted intervention, according to Warren and colleagues.

“Early identification of mCNS in IBC using surveillance brain MRI may facilitate the identification of limited intracranial disease burden, thus enabling focal local therapy with surgery and/or stereotactic radiosurgery,” explained Warren and colleagues. “The high incidence of mCNS in patients with IBC and the high utilization of WBRT in our study lends support to the investigation of surveillance brain MRI in this patient population.

In an accompanying editorial, Ajay Dhakal, MBBS and Carey K. Anders, M.D. conceded that a randomized, controlled trial is necessary to validate and demonstrate the benefits of screening brain MRI in patients with IBC.⁴ However, they maintain that the high sensitivity and specificity of brain MRI for detecting brain metastasis would help mitigate cost-effectiveness concerns and risks such as overdiagnosis.

“We posit that routine brain MRI screening could identify patients with smaller, fewer, asymptomatic BrMs that may be candidates for more focused local therapy,” wrote Dr. Dhakal, an assistant professor at the James P. Wilmot Cancer Center at the University of Rochester Medical Center, and Dr. Anders, a professor of medicine and chief of the Division of Medical Oncology at the Duke University School of Medicine. “Such an approach could lead to earlier diagnosis, avoidance of WBRT, and potentially circumvent the emergence of possibly permanent neurologic deficits.”

In addition to the retrospective study design, Warren and colleagues said another limitation of the study was the data coming from one institution. They also acknowledged that the cases in the study were drawn from a long time period covering 1997 to 2019, and changes in the diagnosis and treatment of patients with mCNS disease occurred during that time period.

The study authors pointed out that a prospective study looking at the use of screening brain MRI for patients with stage III IBC is currently underway.

References

1. Warren LEG, Niman SM, Remolano MC, et al. Incidence, characteristics, and management of central nervous system metastases in patients with inflammatory breast cancer. Cancer. 2022 Oct 10. doi: 10.1002/cncr.34441. Online ahead of print.

2. Brown PD, Jaeckle K, Ballman KV, et al. Effect of radiosurgery alone vs. radiosurgery with whole brain radiation therapy on cognitive function in patients with 1 to 3 brain metastases: a randomized clinical trial. JAMA. 2016;316(4):401-409.

3. Aoyama H, Shirato H, Tago M, et al. Stereotactic radiosurgery plus whole-brain radiation therapy vs. stereotactic radiosurgery alone for treatment of brain metastases: a randomized controlled trial. JAMA. 2006;295(21):2483-2491.

4. Dhakal A, Anders CK. Screening brain MRI in inflammatory breast cancer: is it time? Cancer. 2022 Oct 10. doi: 10.1002/cncr.34442. Online ahead of print.