Real‐world outcomes using PD‐1 antibodies and BRAF + MEK inhibitors for adjuvant melanoma treatment from 39 skin cancer centers in Germany, Austria and Switzerland

Abstract Background Programmed death‐1 (PD‐1) antibodies and BRAF + MEK inhibitors are widely used for adjuvant therapy of fully resected high‐risk melanoma. Little is known about treatment efficacy outside of phase III trials. This real‐world study reports on clinical outcomes of modern adjuvant melanoma treatment in specialized skin cancer centers in Germany, Austria and Switzerland. Methods Multicenter, retrospective study investigating stage III–IV melanoma patients receiving adjuvant nivolumab (NIV), pembrolizumab (PEM) or dabrafenib + trametinib (D + T) between 1/2017 and 10/2021. The primary endpoint was 12‐month recurrence‐free survival (RFS). Further analyses included descriptive and correlative statistics, and a multivariate linear‐regression machine learning model to assess the risk of early melanoma recurrence. Results In total, 1198 patients from 39 skin cancer centers from Germany, Austria and Switzerland were analysed. The vast majority received anti PD‐1 therapies (n = 1003). Twelve‐month RFS for anti PD‐1 and BRAF + MEK inhibitor‐treated patients were 78.1% and 86.5%, respectively (hazard ratio [HR] 1.998 [95% CI 1.335–2.991]; p = 0.001). There was no statistically significant difference in overall survival (OS) in anti PD‐1 (95.8%) and BRAF + MEK inhibitor (96.9%) treated patients (p > 0.05) during the median follow‐up of 17 months. Data indicates that anti PD‐1 treated patients who develop immune‐related adverse events (irAEs) have lower recurrence rates compared to patients with no irAEs (HR 0.578 [95% CI 0.443–0.754], p = 0.001). BRAF mutation status did not affect overall efficacy of anti PD‐1 treatment (p > 0.05). In both, anti PD‐1 and BRAF + MEK inhibitor treated cohorts, data did not show any difference in 12‐month RFS and 12‐month OS comparing patients receiving total lymph node dissection (TLND) versus sentinel lymph node biopsy only (p > 0.05). The recurrence prediction model reached high specificity but only low sensitivity with an AUC = 0.65. No new safety signals were detected. Overall, recorded numbers and severity of adverse events were lower than reported in pivotal phase III trials. Conclusions Despite recent advances in adjuvant melanoma treatment, early recurrence remains a significant clinical challenge. This study shows that TLND does not reduce the risk of early melanoma recurrence and should only be considered in selected patients. Data further highlight that variables collected during clinical routine are unlikely to allow for a clinically relevant prediction of individual recurrence risk

Midkine rewires the melanoma microenvironment toward a tolerogenic and immune-resistant state.

An open question in aggressive cancers such as melanoma is how malignant cells can shift the immune system to pro-tumorigenic functions. Here we identify midkine (MDK) as a melanoma-secreted driver of an inflamed, but immune evasive, microenvironment that defines poor patient prognosis and resistance to immune checkpoint blockade. Mechanistically, MDK was found to control the transcriptome of melanoma cells, allowing for coordinated activation of nuclear factor-κB and downregulation of interferon-associated pathways. The resulting MDK-modulated secretome educated macrophages towards tolerant phenotypes that promoted CD8+ T cell dysfunction. In contrast, genetic targeting of MDK sensitized melanoma cells to anti-PD-1/anti-PD-L1 treatment. Emphasizing the translational relevance of these findings, the expression profile of MDK-depleted tumors was enriched in key indicators of a good response to immune checkpoint blockers in independent patient cohorts. Together, these data reveal that MDK acts as an internal modulator of autocrine and paracrine signals that maintain immune suppression in aggressive melanomas.We thank the colleagues at the CNIO Melanoma Group, as well as those at the laboratories of H. Peinado and Manuel V. (CNIO), for help and support, I. Blanco, S. Ruiz, V. Granda, S. Rueda (CNIO) and the Animal Facility, Histopathological Unit, Confocal Microscopy Unit and Crystallography and Protein Engineering Unit of CNIO for assistance with the mouse colonies and histopathological and protein analyses, and D. Sancho (CNIC) for the B16-OVAGFP cells and OT-I mouse strain, and for scientific guidance. P. Turko (University of Zurich) provided advice on the statistical analyses of tissue microarrays. We also thank the donors and the Biobank Hospital Universitario Puerta De Hierro Majadahonda (HUPHM)/Instituto De Investigacion Sanitaria Puerta De Hierro-Segovia De Arana (IDIPHISA) (PT17/0015/0020 in the Spanish National Biobanks Network) for the human specimens used in this study. M.S.S. is funded by grants from the Spanish Ministry of Economy and Innovation (SAF2017-89533-R), Team Science and Established Investigator awards by the Melanoma Research Alliance, and grants from Worldwide Cancer Research and Fundacion 'La Caixa' Health Research 2019. M.S.S., P.O.-R. and J.L.R.-P. are funded by a collaborative grant from the Asociacion Espanola Contra el Cancer (AECC). D.O. is funded by grants from the Spanish Ministry of Health (AES-PIS PI18/1057) and 'Fundacion BBVA-Becas Leonardo a Investigadores y Creadores Culturales 2018'. D.C.-W. was a recipient of a predoctoral fellowship from Fundacion 'La Caixa' and is currently funded by the AECC. The CNIO Proteomics Unit belongs to ProteoRed, PRB2-ISCIII, supported by grant PT13/0001. N.I. and J.M. are funded by SAF2013-45504-R (MINECO). J.M. is also supported by Ramon y Cajal Programme (MINECO) RYC-2012-10651. M.C.-A. and X.C. were funded by the Immutrain Marie Skodowska-Curie ITN Grant. S.H. received funding from the European Union's Horizon 2020 Research and Innovation Programme under grant agreement numberS