Survival after Introduction of Adjuvant Treatment in Stage III Melanoma: A Nationwide Registry-Based study
Menée en Suède à partir de données 2016-2020 portant sur 1 371 patients atteints d'un mélanome de stade III, cette étude analyse l'impact, sur la survie globale à 2 ans, de l'utilisation de traitements adjuvants
Background: Adjuvant treatments with PD-1 and BRAF+MEK inhibitors significantly prolong recurrence-free survival in stage III cutaneous melanoma. Yet, the effect on overall survival is still unclear. Based on recurrence-free survival outcomes, these treatments have been approved and widely implemented. The treatments have significant side effects and costs, and the overall survival effect remains a highly anticipated outcome. Methods: Clinical and histopathological parameters were obtained from the Swedish Melanoma Registry for patients diagnosed with stage III melanoma between 2016 and 2020. The patients were divided depending on if they were diagnosed before or from July 2018, based on the timepoint when adjuvant treatment was introduced in Sweden. Patients were followed until the end of 2021. In this cohort study melanoma-specific and overall survival were calculated using the Kaplan-Meier method and Cox-regression analyses. Results: There were 1371 patients diagnosed with stage III melanoma in Sweden in 2016-2020. The 2-year overall survival rates, comparing the 634 patients in the pre-cohort and the 737 in the post-cohort, were 84.3% (95% CI 81.4-87.3) and 86.1% (95% CI 83.4-89.0), respectively, with an adjusted HR 0.91 (95% CI 0.70-1.19, P = 0.51). Further, no significant overall or melanoma-specific survival differences were seen when comparing the pre- and the post-cohort in different subgroups for age, sex or tumor characteristics. Conclusions: In this nationwide, population and registry-based study, no survival benefit was detected in patients diagnosed before or after the implementation of adjuvant treatment in stage III melanoma. These findings encourage a careful assessment of the current recommendations on adjuvant treatment.