Since the Food and Drug Administration first approved checkpoint blockade immunotherapy (CBI) and BRAFV600-targeted therapy in 2011, survival times for patients with melanoma brain metastases (MBMs) have significantly improved, with a 91% increase in 4-year overall survival (OS) from 7.4% to 14.1%.
“The management of advanced melanoma has traditionally been tempered by limited responses to conventional therapies, resulting in a median overall survival (OS) of less than 1 year,” wrote J. Bryan Iorgulescu, MD, of Brigham and Women’s Hospital in Boston, and his colleagues. The report was published in Cancer Immunology Research. “The landscape of advanced melanoma treatment was revolutionized” by the approval of immunotherapy agents, beginning in 2011.
The current, retrospective study involved 2,753 patients with stage IV melanoma. Patient data were drawn from the National Cancer Database, with diagnoses made between 2010 and 2015. Patient management, overall survival, and disease characteristics were evaluated.
During initial review, the researchers found that 35.8% of patients with stage IV melanoma had brain involvement. These patients were further categorized by those with MBM only (39.7%) versus those with extracranial metastatic disease (60.3%), which included involvement of lung (82.9%), liver (8.1%), bone (6.0%), and lymph nodes or distant subcutaneous skin (3%). MBM-only disease was independently predicted by both younger age and geographic location.
Patients receiving first-line CBI therapy demonstrated improved 4-year OS (28.1% vs. 11.1%; P less than.001) and median OS (12.4 months vs. 5.2 months; P less than .001).
Improvements with CBI were most dramatic in patients with MBM-only disease. In these cases, 4-year OS improved from 16.9% to 51.5% (P less than .001), while median OS jumped from 7.7 months to 56.4 months (P less than .001).
Improved OS was also associated with fewer comorbidities, younger age, management at an academic cancer center, single-fraction stereotactic radiosurgery, and resection of the MBM.
“Our findings help bridge the gaps in early clinical trials of CBIs that largely excluded stage IV melanoma patients with MBMs, with checkpoint immunotherapy demonstrating a more than doubling of the median and 4-year OS of MBMs,” the authors concluded.
SOURCE: Iorgulescu et al. Cancer Immunol Res. 2018 July 12 doi: 10.1158/2326-6066.CIR-18-0067.