Predictive and on-treatment monitoring biomarkers in advanced melanoma: Moving toward personalized medicine

The treatment armamentarium for patients with metastatic melanoma has increased substantially over the past decade with the regulatory approval of targeted BRAF + MEK inhibitors and immune checkpoint inhibitors, which have vastly improved long-term outcomes. Recently, these advances have been rapidly translated to the high-risk adjuvant setting. Primary and acquired resistance to both immune and molecularly targeted agents, however, remains a challenge. Therefore, biomarkers predictive of response to therapy that can be assessed prior to initiation of treatment and early during the course of therapy are critical. Equally important is on-treatment biomarker monitoring that may predict the likelihood of treatment failure and disease relapse. This review will summarize recent advances in the understanding of biomarkers for patients with advanced melanoma, emphasizing emerging baseline predictive factors and on-treatment monitoring of biomarkers that aim to establish truly personalized treatment.