Adjuvant treatment decisions of patients with stage IIB/C and III melanoma in routine clinical practice

The introduction of modern adjuvant therapies for melanoma has marked a paradigm shift for stage III in 2018 and stage IIB/C in 2022. However, patients' decisions sometimes deviate from the advice of physicians. This retrospective study aimed to evaluate adjuvant treatment decisions, influencing factors, and outcomes for melanoma patients with stage IIB/C and III receiving routine care at the Vivantes Skin Cancer Center, which operates across three locations in Berlin, Germany. We analysed tumour board recommendations, patient treatment decisions, potential determinants, and outcomes for melanoma patients with stage IIB/C and III treated at our centre from January 2019 to December 2022 (stage III) or September 2023 (stage IIB/C). Descriptive statistics, multivariate regression, and Kaplan-Meier analyses were employed. A total of 356 cases involving adjuvant treatment decisions were identified. The tumour board recommended adjuvant treatment in 76.3% of all cases and with an option of modern adjuvants in 95.2%. For stage IIB/C, the recommendation rate significantly increased after approval of PD-1 inhibitors (90.2% vs. 35.5%, p<0.001). Given the option of approved modern adjuvants, 73.8% of patients decided to take adjuvant therapy, among them 81.7% with stage III, but only 43.1% with stage IIB/C (p<0.001). Major determinants of tumour board recommendations and patients' decisions were tumour stage and age, and the patients' most common counterargument was fear of adverse events. Adjuvant therapy led to significantly improved recurrence-free survival in patients with stage III (p=0.016). Modern adjuvant therapies are well established in routine clinical practice, but better accepted in patients with stage III than stage IIB/C.