Changing the standard of care for treating melanoma brain metastases

Melanoma brain metastasis presentation, treatment, and outcomes in the age of targeted and immunotherapies

BACKGROUND

Historically, the prognosis for patients who have melanoma brain metastasis (MBM) has been dismal. However, breakthroughs in targeted and immunotherapies have improved long-term survival in those with advanced melanoma. Therefore, MBM presentation, prognosis, and the use of multimodality central nervous system (CNS)-directed treatment were reassessed.

METHODS

In this retrospective study, the authors evaluated patients with MBM who received treatment at Memorial Sloan Kettering Cancer Center between 2010 and 2019. Kaplan-Meier methodology was used to describe overall survival (OS). Recursive partitioning analysis and time-dependent multivariable Cox modeling were used to assess prognostic variables and to associate CNS-directed treatments with OS.

RESULTS

Four hundred twenty-five patients with 2488 brain metastases were included. The median OS after an MBM diagnosis was 8.9 months (95% CI, 7.9-11.3 months). Patients who were diagnosed with MBM between 2015 and 2019 experienced longer OS compared to those who were diagnosed between 2010 and 2014 (OS, 13.0 months [95% CI, 10.47-17.06 months] vs 7.0 months [95% CI, 6.1-8.3 months]; P = .0003). Prognostic multivariable modeling significantly associated shortened OS independently with leptomeningeal dissemination (P < .0001), increasing numbers of brain metastases at diagnosis (P < .0001), earlier MBM diagnosis year (P = .0008), higher serum levels of lactate dehydrogenase (P < .0001), receipt of immunotherapy before MBM diagnosis (P = .003), and the presence of extracranial disease (P = .02). The use of different CNS-directed treatment modalities was associated with presenting symptoms, diagnosis year, number and size of brain metastases, and the presence of extracranial disease. Multivariable analysis demonstrated improved survival for patients who underwent craniotomy (P = .01).

CONCLUSIONS

The prognosis for patients with MBM has improved within the last 5 years, coinciding with the approval of PD-1 immune checkpoint blockade and combined BRAF/MEK targeting. Improving survival reflects and may influence the willingness to use aggressive multimodality treatment for MBM.

LAY SUMMARY

Historically, melanoma brain metastases (MBM) have carried a poor survival prognosis of 4 to 6 months; however, the introduction of immunotherapy and targeted precision medicines has altered the survival curve for advanced melanoma. In this large, single-institution, contemporary cohort, the authors demonstrate a significant increase in survival of patients with MBM to 13 months within the last 5 years of the study. A worse prognosis for patients with MBM was significantly associated with the number of metastases at diagnosis, previous exposure to immunotherapy, spread of disease to the leptomeningeal compartment, serum lactate dehydrogenase elevation, and the presence of extracranial disease. The current age of systemic treatments has also been accompanied by shifts in the use of central nervous system-directed therapies.

Comprehensive Clinical Trial Data Summation for BRAF-MEK Inhibition and Checkpoint Immunotherapy in Metastatic Melanoma

This review focuses on checkpoint and BRAF inhibitors, exploring outcomes based on clinical and disease characteristics to identify trends that might inform treatment decisions for the management of melanoma.

Background.

Immune checkpoint inhibitors, along with BRAF and MEK inhibitors, have dramatically changed the management of and outlook for patients with metastatic melanoma. Analyses of long‐term follow‐up data and subanalyses based on disease characteristics may inform clinical decision making.

Methods.

Reports of clinical trials in metastatic melanoma published between January 1, 2012, and August 30, 2018, were identified using PubMed (terms: melanoma AND [dabrafenib OR trametinib OR vemurafenib OR cobimetinib OR encorafenib OR ipilimumab OR nivolumab OR pembrolizumab]) and were systematically reviewed. Relevant congress proceedings were also assessed. Efficacy data from key phase III trials were analyzed and trends identified.

Results.

Substantial improvements in objective response rates, progression‐free survival, and overall survival were documented across 14 identified publications. Subgroup findings supported that patients with lower disease burden derive greater benefit than patients with more advanced disease, limiting the value of disease burden in the clinical decision‐making process. However, these agents consistently conferred benefits despite the presence of poor prognostic features. Several clinically relevant questions remain, including how best to sequence immune checkpoint inhibitors and combination targeted therapy.

Conclusion.

This research, coupled with ongoing investigations, including those on predictive biomarkers, suggests that the treatment decision‐making process is likely to become more nuanced.

Implications for Practice.

The management of melanoma has been rapidly advancing with new classes of agents, including immune checkpoint and BRAF inhibitors. With long‐term follow‐up, their impact on response rates and survival outcomes is well documented. Additional findings from subgroup analyses suggest that patients with lower disease burden derive greater benefit, yet both consistently confer benefit in patients with higher disease burden. Currently, there is a paucity of data to guide first‐line treatment selection between immunotherapy and BRAF‐targeted therapy in clinical practice or to estimate their impact when sequenced. Gaining these insights will facilitate a more nuanced management approach.