Epidemiology and Treatment Patterns of Stage III Resectable Melanoma Treated with Adjuvant Therapy: A Real-World Study Using the SNDS Database in France

INTRODUCTION: Before the advent of neoadjuvant immunotherapy (IO) in macroscopic disease, IO and targeted therapies were recommended as adjuvant therapies for the treatment of stage III resectable melanoma. However, real-world evidence on their use and outcomes remains limited. This study described treatment patterns and survival outcomes among patients with stage III resectable melanoma who received adjuvant therapy in France. METHODS: This retrospective cohort study used data from the exhaustive French national health data system (SNDS) to identify adults initiating adjuvant nivolumab (NIVO), pembrolizumab (PEM), or dabrafenib-trametinib (DT) between January 1, 2019, and December 31, 2021. Patients were followed until December 31, 2023, or death. Exclusion criteria included prior metastatic disease, other active cancers, or prior use of study drugs. Outcomes included treatment patterns at recurrence, described using Sankey diagrams, and survival (recurrence-free survival [RFS], overall survival [OS]), assessed using a Kaplan-Meier estimator. RESULTS: The study population consisted of 2612 patients with resected stage III melanoma initiating an adjuvant therapy. Of them, 1483 (56.8%) received NIVO, 635 (24.3%) had PEM, and 494 (18.9%) had DT. Median (Q1-Q3) age was 64.0 (52.0-73.0) years for NIVO, 64.0 (51.0-74.0) years for PEM, and 58.0 (46.0-70.0) years for DT. Median follow-up was 39.5 months for NIVO, 38.9 months for PEM, and 36.9 for DT. At 36 months, RFS (95% CI) was 50.7% (48.0%-53.2%) for NIVO, 52.7% (48.6-56.7%) for PEM, and 48.3% (43.7-52.7%) for DT. Finally, 36-month OS (95% CI) was 81.8% (79.7-83.8%) for NIVO, 82.3% (79.0-85.2%) for PEM, and 74.4% (70.1-78.2%) for DT. Immunotherapy represented 75% of therapies at recurrence among patients with adjuvant NIVO/PEM and 55% among patients with adjuvant DT. CONCLUSION: Immunotherapy is the cornerstone of adjuvant and recurrence treatment in stage III melanoma, representing the vast majority of adjuvant therapies and recurrence therapies. Despite effective therapies, recurrence remains frequent, with around half of relapses at 3 years, underscoring the need for continued optimization of treatment strategies.