Brain Radiotherapy Is Effective in Patients With Advanced Breast Cancer, Brain Metastases

A study found that combining central nervous system (CNS) radiotherapy with pyrotinib and capecitabine improves CNS progression-free survival (PFS) in patients with ERBB2-positive breast cancer with brain metastases. The findings appeared in JAMA Oncology. 

In this single-arm, single-center, phase 2, nonrandomized clinical trial, researchers assessed 40 female patients (average age, 50.5 years) with ERBB2-positive breast cancer and brain metastases.

The population of interest received either fractionated stereotactic radiotherapy or whole-brain radiotherapy. Treatment with pyrotinib (400 mg, once daily) and capecitabine (1000 mg/m², twice daily, on days 1-14 of each 21-day cycle) was initiated from the first day of radiotherapy to the seventh day after the completion of radiotherapy and continued until disease progression or unacceptable toxic effects.

The primary end point of interest was defined as the 1-year CNS PFS rate. The study’s secondary outcomes included CNS objective response rate, PFS, overall survival (OS), safety, and changes in neurocognitive function.

The results showed that the 1-year CNS PFS rate was 74.9%, and the median CNS PFS was 18 months. Moreover, the study showed that the average PFS rate was 66.9% (95% CI, 53.1%-84.2%), and the median PFS was 17.6 months (95% CI, 12.8-34.1). The CNS objective response rate was 85%. The investigators noted that the median OS was not reached. The most common grade 3 or 4 adverse event reported was diarrhea (7.5%). The investigators further noted that most patients maintained neurocognitive function.

“The results of this trial suggest that radiotherapy combined with pyrotinib and capecitabine is associated with long intracranial survival benefit in patients with ERBB2-positive advanced breast cancer and brain metastases, with an acceptable safety profile. This combination deserves further validation,” the researchers concluded.