Checkpoint blockade immunotherapies significantly improve the survival of patients with melanoma brain metastases, according to a new study. Data from > 1500 cancer programs across the USA supplied the researchers with a large enough dataset to enable them to effectively analyze the effectiveness of the immunotherapies in this specific and underrepresented patient population.
The study results were published in the journal Cancer Immunology Research.
According to the American Cancer Society, in 2018 > 91,000 new melanomas will be diagnosed and ~9000 people are expected to die of melanoma in the United States. For those cases that are detected and diagnosed as early-stage melanoma, surgery alone is often effective enough to cure the patient of the disease. However, for those diagnosed with late-stage melanoma, treatment becomes more challenging and the rate of survival is considerably reduced (< 1 year).
A common and difficult-to-treat symptom of late-stage melanoma (Stage IV) is the development of brain metastases. This patient population is often underrepresented in immunotherapy clinical trials as there is concern that the treatment would be unable to reach the drug target (brain tumor) due to difficulty traversing the blood-brain-barrier, and fear that it could potentially disrupt the efficacy of other treatments.
To determine whether the benefits of immunotherapy extended to patients with melanoma with brain metastases, data from > 2,700 patients was compiled and analyzed.
"Through the use of nationwide cancer data, for the first time we can evaluate the impacts on survival that these exciting new therapies have for patients with melanoma brain metastases," said Timothy Smith, MD, PhD, MPH, of Brigham and Women's Hospital/Harvard Medical School, senior author of the paper in a recent press release.
Results showed that:
- Patients receiving checkpoint blockade immunotherapy had an average survival of 12.4 months compared to 5.2 months for patients not receiving immunotherapy.
- Patients receiving checkpoint blockade immunotherapy had a 4-year survival rate of 28.1% compared to 11.1% for patients not receiving immunotherapy.
- Patients with cancer that had not yet metastasized beyond the brain showed even more dramatic improvements in survival.
"This highlights the power of population data to help answer critical, but previously unanswerable, questions that we face every day in clinical practice." Smith commented in a recent press release.
"The results of our analyses indicate that immune checkpoint inhibitors can achieve a meaningful therapeutic benefit for metastatic melanoma, including spread to the central nervous system. At the same time, not all patients benefit, indicating that much research is still required to optimize the potential of anti-tumor immune responses for CNS metastatic disease." concludes co-author David Reardon, MD, of Dana-Farber and Harvard Medical School.