President Jimmy Carter's battle with metastatic melanoma to the brain has placed increased attention on management of this disease. President Carter was treated with focused stereotactic radiation to the brain and anti-PD-1 therapy. Researchers at Moffitt Cancer Center recently reported the first series of patients treated with this combined modality approach. They found that radiation therapy combined with the immune-targeting drug nivolumab in melanoma patients with brain metastases is safe and improves their survival compared to historical data.
Nivolumab is a therapeutic agent that targets a protein on immune cells called PD-1. Binding of PD-1 to its ligand PD-L1, which is found on tumor cells, causes immune cells to decrease their activity and allows cancer cells to escape immune detection and cell death. Nivolumab blocks the PD-1/PD-L1 interaction and restimulates the body's own immune system to target tumor cells. Nivolumab has been approved by the Food and Drug Administration to treat advanced non-small cell lung cancer, renal cell carcinoma, and melanoma; however, the impact of nivolumab on brain metastases is unclear.
Common treatment options for metastatic brain metastases are surgery, whole brain radiation therapy and focused radiation therapy called stereotactic radiation. Researchers from Moffitt's Departments of Radiation Oncology, Cutaneous Oncology, and Neuro-Oncology worked together to assess if nivolumab combined with stereotactic radiation therapy was a safe and effective treatment option for patients with melanoma brain metastases.
The team retrospectively analyzed data from 26 patients who were treated with nivolumab and stereotactic radiotherapy. The patients had participated in two separate clinical trials at Moffitt.
The researchers discovered that the combination of nivolumab and stereotactic radiation therapy was safe in patients with both resected and unresected brain metastases. Of the 26 metastatic melanoma patients, only 1 patient experienced treatment-related headaches and no other neurologic toxicities or scalp reactions were reported.
Nivolumab combined with stereotactic radiation also appears to improve patient survival and reduce the development of new metastatic lesions in the brain when compared to historical data. Patients with unresected metastatic disease had a median overall survival of 11.8 months from the start of radiation therapy and 12 months from the start of nivolumab treatment. This is an improvement from historical levels of survival for melanoma patients with brain metastases who on average survive 8 to 10 months after surgery or radiation alone.
"This study shows the two treatments can be combined safely and may work synergistically in the treatment of melanoma brain metastases. This study is a step forward as we work towards improving outcomes for patients with brain metastases," said Kamran A. Ahmed, M.D., lead author of the study and resident in Department of Radiation Oncology at Moffitt.
The research was published in the Annals of Oncology and was also highlighted in the American Society of Clinical Oncology's Cancer in the News and by the website Cancer Therapy Advisor.