Asymptomatic brain metastasis in stage 4 breast cancer requires reevaluation of screening guidelines

A new study led by researchers at Moffitt Cancer Center shows that asymptomatic brain metastasis is more common in stage 4 breast cancer patients than previously believed. The study, published in Neuro-Oncology, suggests that doctors may need to rethink current screening guidelines for detecting brain metastasis in patients without symptoms.

Researchers examined 101 asymptomatic patients diagnosed with stage 4 breast cancer, including triple-negative, HER2-positive and hormone receptor-positive/HER2-negative breast cancer. These patients underwent MRI scans to check for brain metastasis, with a follow-up MRI six months later if the initial scan showed no signs of cancer spread.

Of the patients who completed the initial MRI, 14% had brain metastasis. The rates by subtype were:

• 18% in triple-negative breast cancer
• 15% in HER2-positive breast cancer
• 10% in hormone receptor-positive/HER2-negative breast cancer

After the second MRI, the number of patients with brain metastasis grew to about 25% in each subtype. Following diagnosis, patients went on to receive early treatment for their brain metastases, including changes in systemic therapy and local therapies.

Our study suggests that asymptomatic brain metastasis is quite common in stage 4 breast cancer. Although larger studies are needed to confirm our findings, given the improvements in systemic and local therapies for breast cancer brain metastasis, the time may be appropriate to reconsider current guidelines that recommend against routine MRI surveillance in late stage breast cancer."

Kamran Ahmed, M.D., associate member and section chief for Breast Radiation Oncology at Moffitt and principal investigator of the study

This study was supported by the Florida Breast Cancer Foundation.