Novel adjuvant options for cutaneous melanoma

Patients with resected stage III and IV melanoma have a high risk of recurrence. As the outcomes for patients with metastatic disease have improved dramatically over the past decade due to systemic therapy, more recently so too have the outcomes of patients with resected stage III and IV melanoma with the introduction of checkpoint inhibitor immunotherapy and targeted therapy in the adjuvant setting.

This review outlines the latest clinical trial data, the current adjuvant treatment landscape and its application to clinical practice and expected future progress for the management of early-stage melanoma.

Anti-programmed cell death protein 1 monotherapy and BRAF/MEK inhibitors are currently deemed standard of care for resected stage III melanoma. For patients with stage IIIB [American Joint Committee on Cancer staging system version 7 (AJCCv7)] melanoma, 2-year and 3-year recurrence-free survival is approximately 72% and 65% for nivolumab, 70% and 65.7% for pembrolizumab and 68% and 60% for dabrafenib/trametinib, respectively. For stage IIIC (AJCCv7) melanoma, 2-year and 3-year recurrence-free survival is 60% and 53.5% for nivolumab, 60% and 54.3% for pembrolizumab and 59% and 47% for dabrafenib/trametinib, respectively. Adjuvant treatment is recommended for patients with stage IIIB-IIID [AJCC staging system version 8 (AJCCv8)] melanoma, and may be considered for patients with stage IIIA melanoma. For resected stage IV, nivolumab is the only approved agent; however, recent results from a phase II clinical trial show promising efficacy for combined ipilimumab and nivolumab as well. Long-term data are required to determine which therapy has the greatest impact on overall survival. Schedules, delivery and toxicity are also important factors to consider when selecting adjuvant treatment.

Randomized studies of patients with resected high-risk melanoma have shown that immunotherapy or targeted therapy improve recurrence-free survival compared with placebo/ipilimumab. In order to optimize these treatments, prognostic and predictive biomarkers, as well as strategies to reduce treatment-related toxicities and overcome resistance, are required.