Long-Term Outcomes With Pembrolizumab for NSCLC and Brain Metastases
Posted: Tuesday, August 18, 2020
Treatment of small brain metastases with the checkpoint inhibitor pembrolizumab may improve outcomes in patients with non–small cell lung cancer (NSCLC) and PD-L1 activity, according to an updated analysis of a phase II trial published in The Lancet Oncology. However, patient response depended on the level of PD-L1 the tumor expressed, according to Sarah B. Goldberg, MD, MPH, of the Yale Cancer Center, New Haven, and colleagues.
“We have clearly shown, for the first time, that brain metastasis responds to a targeted immunotherapy for lung cancer,” commented Dr. Goldberg in a Yale Cancer Center press release. “In general, we found the benefit offered by pembrolizumab to the lungs in patients with advanced lung cancer was mirrored in control of their brain tumors.”
A total of 42 patients with stage IV NSCLC and at least one small brain metastasis (5–20 mm) were enrolled in the single-institution, open-label study. All patients were previously untreated or had brain tumors that progressed after radiotherapy. Patients were assigned to one of two treatment groups: group 1 had at least 1% PD-L1 expression (n = 36), and group 2 had less than 1% PD-L1 expression (n = 6).
The investigators found that 29.7% of patients in cohort 1 responded to pembrolizumab, whereas no responses were recorded for patients in cohort 2. Of the patients in cohort 1 who responded to treatment, the overall survival rates were 40% and 34% at 1 and 2 years, respectively. In addition, treatment-related adverse events associated with pembrolizumab included pneumonitis, acute kidney injury, colitis, adrenal insufficiency, and hypokalemia.
Disclosure: For full disclosures of the study authors, visit thelancet.com.