Immune Regulation and Immune Therapy in Melanoma: Review with Emphasis on CD155 Signalling.

Melanoma is commonly diagnosed in a younger population than most other solid malignancies and, in Australia and most of the world, is the leading cause of skin-cancer-related death. Melanoma is a cancer type with high immunogenicity; thus, immunotherapies are used as first-line treatment for advanced melanoma patients. Although immunotherapies are working well, not all the patients are benefitting from them. A lack of a comprehensive understanding of immune regulation in the melanoma tumour microenvironment is a major challenge of patient stratification. Overexpression of CD155 has been reported as a key factor in melanoma immune regulation for the development of therapy resistance. A more thorough understanding of the actions of current immunotherapy strategies, their effects on immune cell subsets, and the roles that CD155 plays are essential for a rational design of novel targets of anti-cancer immunotherapies. In this review, we comprehensively discuss current anti-melanoma immunotherapy strategies and the immune response contribution of different cell lineages, including tumour endothelial cells, myeloid-derived suppressor cells, cytotoxic T cells, cancer-associated fibroblast, and nature killer cells. Finally, we explore the impact of CD155 and its receptors DNAM-1, TIGIT, and CD96 on immune cells, especially in the context of the melanoma tumour microenvironment and anti-cancer immunotherapies.

Predictive Impact of Tumor Mutational Burden on Real-World Outcomes of First-Line Immune Checkpoint Inhibition in Metastatic Melanoma.

PURPOSE: The choice of threshold and reliability of high tumor mutational burden (TMB) to predict outcomes and guide treatment choice for patients with metastatic melanoma receiving first-line immune checkpoint inhibitor (ICI) therapy in the real world is not well known. METHODS: Using a deidentified nationwide (US-based) melanoma clinicogenomic database, we identified a real-world cohort of patients with metastatic melanoma (N = 497) who received first-line monotherapy anti-PD-1 (n = 240) or dual anti-PD-1 and anti-CTLA-4 ICI (n = 257) and had a tissue-based comprehensive genomic profiling test TMB score. RESULTS: TMB-high (TMB-H; ≥10 mutations per megabase [muts/Mb], n = 352, 71%) was independently predictive of superior real-world progression-free survival and overall survival versus TMB-low (<10 mut/Mb, n = 145, 29%) in both mono ICI (hazard ratio [HR], 0.45 [95% CI, 0.32 to 0.63]; P < .001; HR, 0.61 [95% CI, 0.41 to 0.90]; P = .01, respectively) and dual ICI (HR, 0.67 [95% CI, 0.49 to 0.90]; P = .009; HR, 0.61 [95% CI, 0.42 to 0.88]; P = .007, respectively) patients. Dual ICI offered no significant advantage in BRAFwt patients and unexpectedly demonstrated greatest benefit in the TMB 10-19 mut/Mb group, identifying a TMB-very high (≥20 mut/Mb, n = 247, 50%) BRAFmut patient subgroup for whom mono ICI may be preferable. CONCLUSION: TMB-H predicts superior outcomes on ICI while coassessment of BRAF status and TMB may inform first-line regimen choice.

The Fight Tumour Blindness Registry: Efficient capture of high-quality real-world data in uveal melanoma.

OBJECTIVE: To describe the development of a web-based data collection tool to track the management and outcomes of uveal melanoma patients. DESIGN: Description of a clinical registry. PARTICIPANTS: Patients with uveal melanoma. METHODS: A panel of expert ocular oncologists, with input from other relevant specialties and individuals with expertise in registry development, collaborated to formulate a minimum data set to be collected to track patient centred, real-world outcomes in uveal melanoma. This data set was used to create the Fight Tumour Blindness! (FTB!) registry within Save Sight Registries. RESULTS: The data set to be collected includes patient demographics and medical history, baseline visit, follow-up visit including tumour treatment, metastatic staging and surveillance, pathology, and patient-reported questionnaires. The inbuilt mechanisms to ensure efficient and complete data collection are described. CONCLUSIONS: The FTB! registry can be used to monitor outcomes for patients with uveal melanoma. It allows benchmarking of outcomes and comparisons between different clinics and countries.

Computational repurposing of oncology drugs through off-target drug binding interactions from pharmacological databases.

PURPOSE: Systematic repurposing of approved medicines for another indication may accelerate drug development in oncology. We present a strategy combining biomarker testing with drug repurposing to identify new treatments for patients with advanced cancer. METHODS: Tumours were sequenced with the Illumina TruSight Oncology 500 (TSO-500) platform or the FoundationOne CDx panel. Mutations were screened by two medical oncologists and pathogenic mutations were categorised referencing literature. Variants of unknown significance were classified as potentially pathogenic using plausible mechanisms and computational prediction of pathogenicity. Gain of function (GOF) mutations were evaluated through repurposing databases Probe Miner (PM), Broad Institute Drug Repurposing Hub (Broad Institute DRH) and TOPOGRAPH. GOF mutations were repurposing events if identified in PM, not indexed in TOPOGRAPH and excluding mutations with a known Food and Drug Administration (FDA)-approved biomarker. The computational repurposing approach was validated by evaluating its ability to identify FDA-approved biomarkers. The total repurposable genome was identified by evaluating all possible gene-FDA drug-approved combinations in the PM dataset. RESULTS: The computational repurposing approach was accurate at identifying FDA therapies with known biomarkers (94%). Using next-generation sequencing molecular reports (n = 94), a meaningful percentage of patients (14%) could have an off-label therapeutic identified. The frequency of theoretical drug repurposing events in The Cancer Genome Atlas pan-cancer dataset was 73% of the samples in the cohort. CONCLUSION: A computational drug repurposing approach may assist in identifying novel repurposing events in cancer patients with no access to standard therapies. Further validation is needed to confirm a precision oncology approach using drug repurposing.

Symptomatic brain metastases in melanoma.

Although clinical outcomes in metastatic melanoma have improved in recent years, the morbidity and mortality of symptomatic brain metastases remain challenging. Response rates and survival outcomes of patients with symptomatic melanoma brain metastases (MBM) are significantly inferior to patients with asymptomatic disease. This review focusses upon the specific challenges associated with the management of symptomatic MBM, discussing current treatment paradigms, obstacles to improving clinical outcomes and directions for future research.

Globe Salvage and Vision Preservation by Neoadjuvant Darovasertib and Crizotinib in Uveal Melanoma.

PURPOSE: To report the effective use of neoadjuvant darovasertib and crizotinib in a patient with a large uveal melanoma (UM) in his only functional eye. DESIGN: Case report. SUBJECTS: One patient with T4b UM. INTERVENTION: Neoadjuvant darovasertib and crizotinib, followed by plaque brachytherapy. MAIN OUTCOME MEASURES: Objective tumor response and conversion from planned enucleation to placement of fovea- and optic nerve-sparing plaque brachytherapy. RESULTS: A patient with a history of left eye blindness from retinal artery occlusion presented with rapidly declining right eye vision due to a primary UM measuring 18 mm in maximal diameter and 16.5 mm in maximal thickness. To salvage vision, neoadjuvant treatment was initiated using darovasertib and crizotinib. After 6 months of neoadjuvant treatment, which included intraocular lens replacement for tumor-associated cataract, the tumor regressed to 14.1 mm in maximal diameter and 2.6 mm in maximal thickness, enabling treatment with plaque brachytherapy rather than enucleation. CONCLUSIONS: The combination of darovasertib and crizotinib for UM is an effective neoadjuvant strategy that warrants further investigation as an approach to improve visual outcomes from the treatment of primary UM. FINANCIAL DISCLOSURE: The other authors have no proprietary or commercial interest in any materials discussed in this article.

Design, optimisation and standardisation of a high-dimensional spectral flow cytometry workflow assessing T-cell immunophenotype in patients with melanoma.

Objectives: Despite the success of immune checkpoint blockade, most metastatic melanoma patients fail to respond to therapy or experience severe toxicity. Assessment of biomarkers and immunophenotypes before or early into treatment will help to understand favourable responses and improve therapeutic outcomes. Methods: We present a high-dimensional approach for blood T-cell profiling using three multi-parameter cytometry panels: (1) a TruCount panel for absolute cell counts, (2) a 27-colour spectral panel assessing T-cell markers and (3) a 20-colour spectral panel evaluating intracellular cytokine expression. Pre-treatment blood mononuclear cells from patients and healthy controls were cryopreserved before staining across 11 batches. Batch effects were tracked using a single-donor control and the suitability of normalisation was assessed. The data were analysed using manual gating and high-dimensional strategies. Results: Batch-to-batch variation was minimal, as demonstrated by the dimensionality reduction of batch-control samples, and normalisation did not improve manual or high-dimensional analysis. Application of the workflow demonstrated the capacity of the panels and showed that patients had fewer lymphocytes than controls (P = 0.0027), due to lower naive CD4+ (P = 0.015) and CD8+ (P = 0.011) T cells and follicular helper T cells (P = 0.00076). Patients showed trends for higher proportions of Ki67 and IL-2-expressing cells within CD4+ and CD8+ memory subsets, and increased CD57 and EOMES expression within TCRγδ+ T cells. Conclusion: Our optimised high-parameter spectral cytometry approach provided in-depth profiling of blood T cells and found differences in patient immunophenotype at baseline. The robustness of our workflow, as demonstrated by minimal batch effects, makes this approach highly suitable for the longitudinal evaluation of immunotherapy effects.

Immune-related adverse events secondary to immunotherapy in oncology: A guide for general practice.

BACKGROUND: Immunotherapy has reshaped the prognoses for many cancers and is increasingly used in both metastatic and adjuvant settings. There is a high prevalence of immunotherapy side effects, or immune-related adverse events (irAEs), which can affect any organ. Some irAEs can cause permanent or prolonged morbidity and, in rare cases, may be fatal. irAEs can present with mild, non-specific symptoms, resulting in delays to identification and management. OBJECTIVE: We aim to provide a general overview of immunotherapy and irAEs, highlighting common clinical scenarios and general principles of management. DISCUSSION: Cancer immunotherapy toxicity is an important clinical problem that is increasingly relevant to general practice, where patients with adverse events may first present. Early diagnosis and timely intervention are important in limiting the severity and morbidity of these toxicities. The management of irAEs should follow treatment guidelines, in consultation with patients' treating oncology teams.

UHRF1/UBE2L6/UBR4-mediated ubiquitination regulates EZH2 abundance and thereby melanocytic differentiation phenotypes in melanoma.

Cellular heterogeneity in cancer is linked to disease progression and therapy response, although mechanisms regulating distinct cellular states within tumors are not well understood. We identified melanin pigment content as a major source of cellular heterogeneity in melanoma and compared RNAseq data from high-pigmented (HPCs) and low-pigmented melanoma cells (LPCs), suggesting EZH2 as a master regulator of these states. EZH2 protein was found to be upregulated in LPCs and inversely correlated with melanin deposition in pigmented patient melanomas. Surprisingly, conventional EZH2 methyltransferase inhibitors, GSK126 and EPZ6438, had no effect on LPC survival, clonogenicity and pigmentation, despite fully inhibiting methyltransferase activity. In contrast, EZH2 silencing by siRNA or degradation by DZNep or MS1943 inhibited growth of LPCs and induced HPCs. As the proteasomal inhibitor MG132 induced EZH2 protein in HPCs, we evaluated ubiquitin pathway proteins in HPC vs LPCs. Biochemical assays and animal studies demonstrated that in LPCs, the E2-conjugating enzyme UBE2L6 depletes EZH2 protein in cooperation with UBR4, an E3 ligase, via ubiquitination at EZH2's K381 residue, and is downregulated in LPCs by UHRF1-mediated CpG methylation. Targeting UHRF1/UBE2L6/UBR4-mediated regulation of EZH2 offers potential for modulating the activity of this oncoprotein in contexts in which conventional EZH2 methyltransferase inhibitors are ineffective.

A capability framework to inform the fundamental requirements for clinical trial unit development, growth and long term success in outer metropolitan and rural areas.

Background: Participation in clinical trials is linked to improved patient outcomes. Despite this, most trial participants either reside in, or are treated in metropolitan areas. TrialHub developed hub-and-spoke models to support and grow clinical trial units in outer metropolitan and regional/rural centres in order to boost clinical trial engagement and reduce demands of trial participation on patients from outer metropolitan and regional/rural areas. The aim of this project was to establish a capability framework for clinical trial unit growth and development. Methods: An integrative methods study design was used to inform the co-design and development of the capability framework based on data collected in Victoria during 2020-21. This included reviews of the literature and of existing local resources, infrastructure, and staffing; as well as education, mentoring and support, and a needs assessment through multidisciplinary working groups. Results: We developed a capability framework based on the level of support required for outer metropolitan and regional/rural centres with diverse existing capabilities across Victoria. The framework applies a maturity model to assess resources, processes and practices which impact the capacity and capability of centres to conduct trials safely and sustainably. Each level of the model uses a consistent set of factors to describe the core elements required for safe clinical trial delivery. This benchmarking allows targeted investment to ensure safe and high-quality delivery of trials at newly establishing trial units. Conclusion: The capability framework developed by TrialHub provides a basis for staged, planned and successful trial unit development and trial implementation. Further validation of the framework is required.

Immune-related adverse events are associated with therapeutic efficacy of immunotherapy in patients with melanoma brain metastases.

Immunotherapy with T-cell checkpoint inhibitors have changed the treatment landscape for patients with melanoma brain metastases (MBMs), offering increased survival compared with historical outcomes. We sought to identify clinical features associated with intracranial tumour responses or progression-free survival (PFS) in patients with MBMs treated with immunotherapy. Patients with MBMs treated with immunotherapy from August 2013 to March 2020 were identified through local databases. Melanoma disease burdens and immune-related adverse events (irAEs) were assessed retrospectively by review of patient medical records. Efficacy was evaluated by determining objective response rates (ORRs) in brain metastases using immune-Response Evaluation Criteria in Solid Tumours criteria, MBM-specific survival and overall PFS. Twenty-six patients were identified as eligible for this study. The presence and volume of extracranial metastases (ECM) were associated with a non-significant trend of reduced intracranial ORRs and PFS. Patients with irAEs, on the other hand, had significantly increased intracranial ORRs and PFS compared to those without irAEs. Severe, grade ≥3 irAEs and co-occurrence of ≥2 irAEs were also significantly associated with longer PFS. The presence and volume of ECM correlated inversely with development and severity of irAEs. We report a strong association between the development of irAEs and favourable melanoma-specific outcomes in patients with MBMs receiving immunotherapy. Contrary to previous studies, we found that co-occurrence of ECM in these patients was associated with fewer irAEs and reduced treatment efficacy.

The role of surveillance imaging for resected high-risk melanoma.

BACKGROUND: Recommendations for surveillance imaging for resected melanoma vary considerably. This study examined the utility of imaging in patients with a high-risk primary melanoma undergoing a protocolized imaging schedule. METHODS: This retrospective study involved data collection regarding imaging, recurrence, and outcome characteristics for patients referred to the Victorian Melanoma Service from January 2016-April 2020 and managed for resected stage IIC or III melanoma. Patients with a T4b tumor who did not undergo a sentinel lymph node biopsy were included (T4bNX). Recurrences were "clinically detected" if they were primarily detected by patient symptoms or physical examination, or 'imaging-detected' if the patient was asymptomatic. Cox regression models including time-varying co-variates were used to assess the impact of imaging-detected versus clinically-detected recurrence on overall survival. RESULTS: Over a median follow-up time of 2.7 years, 199 patients underwent surveillance imaging (T4bNX:22, IIC:33, IIIA:22, IIIB:60, IIIC:61, IIID:1), and 44% (n = 88) experienced disease recurrence. Imaging detected over half (53%) of all recurrences. In adjusted analyses, mortality risk was reduced after an imaging-detected compared to clinically-detected recurrence at any given time from the start of surveillance (hazard ratio 0.25, 95% confidence interval 0.10-0.66, p = .005). CONCLUSION: Our study indicates that routine imaging in the early follow-up period of resected T4bNX, stage IIC and III melanoma plays an important role in the detection of asymptomatic recurrences. Imaging-detected recurrence may be associated with a survival benefit and studies with more prolonged follow-up are required to confirm these findings.

Immune checkpoint inhibitors and the risk of major atherosclerotic cardiovascular events in patients with high-risk or advanced melanoma: a retrospective cohort study.

BACKGROUND: Immune checkpoint inhibitors (ICI) are associated with immune-mediated adverse effects, potentially involving any organ. ICI has also been associated with an increased risk of cardiovascular disease in cancer populations. OBJECTIVE: To characterize the incidence and risk of major atherosclerotic cardiovascular events associated with ICI use in a high-risk and advanced melanoma population. METHODS: We conducted a retrospective cohort study of patients with high-risk or advanced melanoma (AJCC stage II, III or IV) presenting to an academic tertiary hospital between 2015-2020. The main outcome was major atherosclerotic cardiovascular events (MACE) including acute myocardial infarction, ischemic stroke, acute limb ischemia and coronary revascularization. RESULTS: The study cohort consisted of 646 patients, including 289 who had been treated with ICI. The incidence of MACE was higher in the ICI treated group (3.6 vs. 0.9 events per 100-person years). After adjusting for age, sex, smoking history and prior BRAF and/or MEK inhibitor use, ICI treatment was associated with an increased risk of MACE (HRadj 2.8, 95% CI 1.1-6.9, p = 0.03). Elevated risk was especially pronounced in patients with a past history of MACE (HR 14.4, 95% CI 1.9-112.3, p = 0.01). CONCLUSION: Patients with high-risk or advanced melanoma are at an increased risk of atherosclerotic cardiovascular events following ICI treatment, particularly those with a history of cardiovascular disease.

Yield of baseline imaging for distant metastases in high-risk primary melanoma.

BACKGROUND: The yield of baseline imaging in patients presenting with higher risk primary tumours, at least American Joint Committee on Cancer 8th edition stage IIC or III melanoma, is unclear. METHODS: This retrospective study included patients referred to the Victorian Melanoma Service from January 2017 to April 2020, diagnosed with at least stage IIC or stage III melanoma. Patients with a T4b tumour and no sentinel lymph node biopsy were included as 'T4bNX'. RESULTS: One hundred and sixty-four patients (median age 65 years) with baseline imaging (T4bNX: 19, IIC: 30, IIIA: 21, IIIB: 43, IIIC: 50, IIID: 1) were included. The majority were male (73%), and those with T4bNX melanoma tended to be older (median age 79 years). Distant metastases were detected in 21% (4/19) of T4bNX, 3% (1/30) of stage IIC, 0% (0/21) of stage IIIA, and 6% (6/94) of stages IIIB-D melanoma patients. All stage III patients with distant metastases had palpable lymphadenopathy a presentation. Two patients had brain metastases, both of whom had T4bNX melanoma and synchronous extra-cranial metastases. CONCLUSIONS: Compared to stage IIC, baseline imaging detects higher rates of extra-cranial distant disease in stages IIIB-D and T4bNX melanoma. Intracranial imaging has greater yield in patients with distant extra-cranial disease.

Developing an Australian Melanoma Clinical Outcomes Registry (MelCOR): a protocol paper.

INTRODUCTION: Australia has the highest incidence of melanoma in the world with variable care provided by a diverse range of clinicians. Clinical quality registries aim to identify these variations in care and provide anonymised, benchmarked feedback to clinicians and institutions to improve patient outcomes. The Australian Melanoma Clinical Outcomes Registry (MelCOR) aims to collect population-wide, clinical-level data for the early management of cutaneous melanoma and provide anonymised feedback to healthcare providers. METHODS AND ANALYSIS: A modified Delphi process will be undertaken to identify key clinical quality indicators for inclusion in the MelCOR pilot. MelCOR will prospectively collect data relevant to these quality indicators, initially for all people over the age of 18 years living in Victoria and Queensland with a melanoma diagnosis confirmed by histopathology, via a two-stage recruitment and consent process. In stage 1, existing State-based cancer registries contact the treating clinician and provide an opportunity for them to opt themselves or their patients out of direct contact with MelCOR. After stage 1, re-identifiable clinical data are provided to the MelCOR under a waiver of consent. In stage 2, the State-based cancer registry will approach the patient directly and invite them to opt in to MelCOR and share identifiable data. If a patient elects to opt in, MelCOR will be able to contact patients directly to collect patient-reported outcome measures. Aggregated data will be used to provide benchmarked, comparative feedback to participating institutions/clinicians. ETHICS AND DISSEMINATION: Following the successful collection of pilot data, the feasibility of an Australia-wide roll out will be evaluated. Key quality indicator data will be the core of the MelCOR dataset, with additional data points added later. Annual reports will be issued, first to the relevant stakeholders followed by the public. MelCOR is approved by the Alfred Ethics Committee (58280/127/20).

Phase I/II trial of concurrent extracranial palliative radiation therapy with Dabrafenib and Trametinib in metastatic BRAF V600E/K mutation-positive cutaneous Melanoma.

BACKGROUND: Concurrent treatment with BRAF inhibitors and palliative radiation therapy (RT) could be associated with increased toxicity, especially skin toxicity. Current Eastern Cooperative Oncology Group (ECOG) consensus guideline recommend ceasing BRAF inhibitors during RT. There is a lack of data regarding concurrent RT with combined BRAF and MEK inhibitors. This single-arm phase I/II trial was designed to assess the safety and tolerability of palliative RT with concurrent Dabrafenib and Trametinib in patients with BRAF-mutant metastatic melanoma. MATERIALS AND METHODS: Patients received Dabrafenib and Trametinib before and during palliative RT to soft tissue, nodal or bony metastases. The RT dose was escalated stepwise during the study period. Toxicity data including clinical photographs of the irradiated area was collected for up to 12 months following completion of RT. RESULTS: Between June 2016 to October 2019, ten patients were enrolled before the study was stopped early due to low accrual rate. Six patients were treated at level 1 (20 Gy in 5 fractions, any location) and 4 patients at level 2a (30 Gy in 10 fractions with no abdominal viscera exposed). All alive patients completed one year of post-RT follow-up. Of the 82 adverse events (AEs) documented, the majority (90%) were grade 1 and 2. Eight grade 3 events (10%) occurred in five patients, only one was treatment-related (grade 3 fever due to Dabrafenib and Trametinib). No patients experienced grade 3 or 4 RT related toxicities, including skin toxicities. One serious AE was documented in relation to a grade 3 fever due to Dabrafenib and Trametinib requiring hospitalisation. CONCLUSIONS: The lack of grade 3 and 4 RT-related toxicities in our study suggests that Dabrafenib and Trametinib may be continued concurrently during fractionated non-visceral palliative RT to extracranial sites.

Evaluation of Crizotinib Treatment in a Patient With Unresectable GOPC-ROS1 Fusion Agminated Spitz Nevi.

IMPORTANCE: Spitz nevi are benign melanocytic neoplasms that classically present in childhood. Isolated Spitz nevi have been associated with oncogenic gene fusions in approximately 50% of cases. The rare agminated variant of Spitz nevi, thought to arise from cutaneous genetic mosaicism, is characterized by development of clusters of multiple lesions in a segmental distribution, which can complicate surgical removal. Somatic single-nucleotide variants in the HRAS oncogene have been described in agminated Spitz nevi, most of which were associated with an underlying nevus spilus. The use of targeted medical therapy for agminated Spitz nevi is not well understood. OBSERVATIONS: A girl aged 30 months presented with facial agminated Spitz nevi that recurred rapidly and extensively after surgery. Owing to the morbidity of further surgery, referral was made to a molecular tumor board. The patient's archival nevus tissue was submitted for extended immunohistochemical analysis and genetic sequencing. Strong ROS1 protein expression was identified by immunohistochemistry. Consistent with this, analysis of whole-genome sequencing data revealed GOPC-ROS1 fusions. These results indicated likely benefit from the oral tyrosine kinase inhibitor crizotinib, which was administered at a dosage of 280 mg/m2 twice daily. An excellent response was observed in all lesions within 5 weeks, with complete flattening after 20 weeks. CONCLUSIONS AND RELEVANCE: Given the response following crizotinib treatment observed in this case, the kinase fusion was believed to be functionally consequential in the patient's agminated Spitz nevi and likely the driver mutational event for growth of her nevi. The repurposing of crizotinib for GOPC-ROS1 Spitz nevi defines a new treatment option for these lesions, particularly in cases for which surgery is relatively contraindicated.

Evolution of late-stage metastatic melanoma is dominated by aneuploidy and whole genome doubling.

Although melanoma is initiated by acquisition of point mutations and limited focal copy number alterations in melanocytes-of-origin, the nature of genetic changes that characterise lethal metastatic disease is poorly understood. Here, we analyze the evolution of human melanoma progressing from early to late disease in 13 patients by sampling their tumours at multiple sites and times. Whole exome and genome sequencing data from 88 tumour samples reveals only limited gain of point mutations generally, with net mutational loss in some metastases. In contrast, melanoma evolution is dominated by whole genome doubling and large-scale aneuploidy, in which widespread loss of heterozygosity sculpts the burden of point mutations, neoantigens and structural variants even in treatment-naïve and primary cutaneous melanomas in some patients. These results imply that dysregulation of genomic integrity is a key driver of selective clonal advantage during melanoma progression.