Toripalimab plus axitinib in patients with metastatic mucosal melanoma: 3-year survival update and biomarker analysis

Combination Immunotherapy for Mucosal Melanoma: Molecular Mechanism, Research Status, and Future Directions

OPINION STATEMENT

Mucosal melanoma is a rare and aggressive subtype of melanoma, accounting for 1%-2% of new cases in the United States in 2023, and 20%-30% in China and other Asian countries. Its origin is often occult, with the lack of early clinical features, the absence of actionable driver mutations, and poor response to immunotherapy, all contributing to its poor prognosis. The rarity of this subtype leads to limited awareness and interventions. Furthermore, due to its immune evasion mechanisms, mucosal melanoma shows resistance to traditional immune checkpoint inhibitors. Consequently, new therapeutic strategies are urgently needed to improve patient outcomes. Recent clinical trials have suggested that combination immunotherapy can overcome immune evasion, reduce resistance to treatment, produce synergistic anti-tumor effects, and improve survival. Epidemiological factors and clinical characteristics play significant roles in diagnosis and prognosis, while the mutational landscape influences responses to immunotherapy. This review provides an overview of these aspects and systematically discusses current research on combination therapies and emerging immunotherapy approaches for mucosal melanoma. It also explores potential future directions for treatment, aiming to enhance therapeutic strategies for this rare cancer and improve patient outcomes.

Dynamic Change of PD-L2 on Circulating Plasma Extracellular Vesicles as a Predictor of Treatment Response in Melanoma Patients Receiving Anti-PD-1 Therapy

Immune checkpoint inhibitors (ICIs) have provided new hope for melanoma patients, however, not all patients benefit. Furthermore, ICI-related therapies cause significant immune-related adverse events that adversely affect patient outcomes. Therefore, there is a pressing need for reliable biomarkers to identify patients most likely to benefit from these treatments. In this study, we employed an extracellular vesicles (EVs) protein expression array to explore the longitudinal membrane protein profiles of plasma-derived EVs from 32 melanoma patients receiving anti-PD-1 and anti-angiogenesis therapy at baseline and early treatment. We found that the dynamic changes in PD-L2 on the EV membrane were associated with treatment response and patient survival. The dynamic change of EV PD-L2 as an indication of treatment efficacy was validated in an independent cohort of melanoma patients treated with anti-PD-1 monotherapy. Plasma-derived PD-L2+ EVs from patients with mucosal melanoma significantly reduced the frequency of granzyme B+ CD8 T cells within the peripheral blood mononuclear cells (PBMCs) of healthy individuals. The inhibitory effect of PD-L2+ EVs on CD8 T cells was further validated using human melanoma cell lines and the B16-F10 mouse model. Although intratumoural injection of PD-L2+ EVs could promote melanoma growth in vivo, tumours with PD-L2+ EVs showed a higher response to anti-PD-1 than those without PD-L2+ EVs. Collectively, our study demonstrates that PD-L2+ EVs inhibit CD8 T cell activation and promote melanoma growth, and changes in PD-L2 on circulating EVs during early treatment could serve as a biomarker for ICI-based therapy.

Comparative efficacy and safety of first-line neoadjuvant therapy for early-stage non-small cell lung cancer based on immune checkpoint inhibitor therapy: a systematic review and network meta-analysis

INTRODUCTION

Although there are a number of neoadjuvant immunotherapy combinations that can be applied to the treatment of perioperative non-small cell lung cancer patients, the optimal treatment combination strategy has not yet been determined.

METHODS

We searched PubMed, EMBASE, Cochrane Library, ClinicalTrials.go and randomised controlled trials (RCTs) from major international conferences for literature related to neoadjuvant immunotherapy combinations published as first-line treatment options for non-small cell lung cancer from the start of the library to 20 February 2024, and performed a systematic review and network meta-analysis.

RESULTS

We analyzed nine studies involving 3431 patients, including eight perioperative neoadjuvant immunotherapy combinations for non-small cell lung cancer. For patients without programmed death-ligand 1(PD-L1) selection, Toripalimab plus chemotherapy provided the best Pathological complete response (PCR) benefit (OR = 32.89,95% CI:7.88-137.32), best Major Pathological response (MPR) benefit (OR = 10.25, 95% CI: 5.81-18.10) and best Event-free survival (EFS) benefit (HR = 0.40,95% CI: 0.28-0.57). Nivolumab plus chemotherapy provided the best surgical resection rate (OR = 1.71, 95% CI:0.87-3.40) and pembrolizumab plus chemotherapy provided the best R0 surgical resection rate (OR = 2.20, 95% CI:1.28-3.79). In contrast, the combination of ipilimumab, nivolumab and chemotherapy, and the combination of toripalimab and chemotherapy were associated with the lowest incidence of adverse events of grade 3 or above during neoadjuvant therapy.

CONCLUSIONS

Our findings suggest that: Toripalimab plus chemotherapy showed better neoadjuvant efficacy and may have an overall survival benefit, but also increased the incidence of serious adverse events during neoadjuvant therapy.

Melanoma-derived extracellular vesicles transfer proangiogenic factors

Angiogenesis, the expansion of pre-existing vascular networks, is crucial for normal organ growth and tissue repair, but is also involved in various pathologies, including inflammation, ischemia, diabetes, and cancer. In solid tumors, angiogenesis supports growth, nutrient delivery, waste removal, and metastasis. Tumors can induce angiogenesis through proangiogenic factors including VEGF, FGF-2, PDGF, angiopoietins, HGF, TNF, IL-6, SCF, tryptase, and chymase. This balance is disrupted in tumors, and extracellular vesicles (EVs) contribute to this by transferring proangiogenic factors and increasing their expression in endothelial cells (ECs). Malignant melanoma, a particular type of skin cancer, accounts for only 1% of skin cancer cases but more than 75% of deaths. Its incidence has risen significantly, with a 40% increase between 2012 and 2022, especially in fair-skinned populations. Advanced metastatic stages have a high mortality due to delayed diagnosis. This review examines the molecular basis of angiogenesis in melanoma, focusing on melanoma-derived EVs and their possible use in new antiangiogenic therapies.

Toripalimab combined with bevacizumab plus chemotherapy as first-line treatment for refractory recurrent or metastatic cervical cancer: a single-arm, open-label, phase II study (JS001-ISS-CO214)

OBJECTIVE

To evaluate the efficacy and safety of adding toripalimab to bevacizumab and platinum-based chemotherapy as first-line treatment for refractory recurrent or metastatic (R/M) cervical cancer (CC).

METHODS

Patients were administered toripalimab (240 mg) + bevacizumab (7.5 mg/kg) combined with platinum-based chemotherapy once every three weeks for six cycles, followed by the maintenance therapy involving toripalimab + bevacizumab once every 3 weeks for 12 months or when disease progression or intolerable toxicity occurred. The primary endpoint was the objective response rate (ORR) per Response Evaluation Criteria in Solid Tumors version 1.1. The secondary endpoints were safety profiles, disease control rate (DCR), progression-free survival (PFS), and overall survival (OS).

RESULTS

Twenty-four patients were enrolled in this study and in the final analysis. The median follow-up duration was 18.6 (range, 3.3-28.5) months. The ORR was 83.3% (95% confidence interval [CI]=62.6-95.3) and the DCR was 95.8% (95% CI=78.9-99.9); 9 (37.5%) patients achieved complete response, 11 (45.8%) achieved partial response, and 3 (12.5%) had stable disease. The median PFS was 22.6 (95% CI=10.4-34.7) months and the median OS was not reached. The most common grade 3 treatment-related adverse events (AEs) were neutropenia (41.7%) and leukopenia (16.7%). The most common immune-related AEs (irAEs) were thyroid dysfunction (37.5%) and increased adrenocorticotropic hormone (37.5%) and serum cortisol levels (33.3%). No grade ≥3 irAEs were observed.

CONCLUSION

Toripalimab combined with bevacizumab and platinum-based chemotherapy show promising clinical efficacy and favorable safety profile, providing an alternative first-line treatment option for patients with R/M CC.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04973904.

Efficacy of axitinib in a US cohort of patients with programmed cell death protein 1-resistant mucosal melanoma

Mucosal melanoma is a rare melanoma subtype, accounting for about 1% of all diagnosed melanomas. It is characterized by an aggressive phenotype with a poor prognosis and a low response rate to approved treatments. We retrospectively analyzed the clinical features, treatments, and outcomes of patients diagnosed with mucosal melanoma treated with axitinib ± anti-programmed cell death protein 1 (PD-1) therapy at a single US referral center between 2018 and 2021. Radiologic response was assessed according to Response Evaluation Criteria in Solid Tumors (RECIST), v1.1. Twenty-three patients were included in this study. In all, 78% were females with a median age of 62 years. The originating site of mucosal melanoma was the sinonasal (35%), genitourinary (35%), and gastrointestinal (30%) tracts. Sixty-five percent of patients had M1c or M1d disease and 0% had BRAF V600 mutations detected. The majority (96%) had prior treatment inclusive of anti-PD-1, with a median of 2 prior lines, and 78% of patients received a combination of axitinib and PD-1 and the median duration of treatment was 3.2 months. The overall response rate was 13% and the disease control rate was 26%. The median progression-free survival was 3.2 months, and the median overall survival was 8.2 months. Overall, the regimen was well tolerated with 39% of patients requiring dose reduction and 9% requiring treatment cessation. Axitinib with anti-PD-1 therapy has modest clinical activity in heavily pretreated patients with mucosal melanoma outside of Asia, including some with long-term benefits. This data supports the worldwide clinical trials evaluating this combination and the role of incorporating vascular endothelial growth factor-based therapy in the therapeutic paradigm for patients with mucosal melanoma.

Regorafenib in patients with pretreated advanced melanoma: a single-center case series

Melanoma patients failing all approved treatment options have a poor prognosis. The antimelanoma activity of regorafenib (REGO), a multitargeted kinase inhibitor, has not been investigated in this patient population. The objective response rate and safety of REGO treatment in advanced melanoma patients was investigated retrospectively. Twenty-seven patients received REGO treatment. All patients had progressed on anti-programmed cell death protein 1 (PD-1) and anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) checkpoint inhibition and BRAF/MEK inhibitors (in case of a BRAF V600 mutation). REGO was administered in continuous dosing and combined (upfront or sequentially) with nivolumab ( n  = 5), trametinib ( n  = 8), binimetinib ( n  = 2), encorafenib ( n  = 1), dabrafenib/trametinib ( n  = 9), or encorafenib/binimetinib ( n  = 7). The best overall response was partial response (PR) in five patients (18.5%) and stable disease in three patients (11.1%). Three of seven (42.8%) BRAF  V600mut patients treated with REGO in combination with BRAF/MEK inhibitors obtained a PR (including regression of brain metastases in all three patients). In addition, PR was documented in a BRAF V600mut patient treated with REGO plus anti-PD-1, and a NRASQ61mut patient treated with REGO plus a MEK inhibitor. Common grade 3-4 treatment-related adverse events included arterial hypertension ( n  = 7), elevated transaminase levels ( n  = 5), abdominal pain ( n  = 3), colitis ( n  = 2), anorexia ( n  = 1), diarrhea ( n  = 1), fever ( n  = 1), duodenal perforation ( n  = 1), and colonic bleeding ( n  = 1). Median progression-free survival was 11.0 weeks (95% confidence interval, 7.1-14.9); median overall survival was 23.1 weeks (95% confidence interval, 13.0-33.3). REGO has a manageable safety profile in advanced melanoma patients, in monotherapy as well as combined with BRAF/MEK inhibitors or PD-1 blocking monoclonal antibodies. The triplet combination of REGO with BRAF/MEK inhibitors appears most active, particularly in the BRAF V600mut patients.

Impact of Treatment Delay in Head and Neck Mucosal Melanoma on Overall Patient Survival

Objectives  Head and neck mucosal melanoma (HNMM) is a rare malignancy with high mortality. This study evaluates the impact of treatment delays on overall survival in HNMM. Design/Setting/Participants  A retrospective review of patients with surgically managed HNMM treated with adjuvant radiation was performed from the 2004-2016 National Cancer Database. Main Outcome Measures  Durations of diagnosis-to-treatment initiation (DTI), surgery-to-radiotherapy initiation (SRT), duration of radiotherapy (RTD), surgery-to-immunotherapy initiation (SIT), diagnosis-to-treatment end (DTE), and total treatment package (TTP) were calculated. Results  A total of 1,011 patients (50.7% female, 90.5% Caucasian) met inclusion criteria. Median DTI, SRT, RTD, SIT, DTE, and TTP were 30, 49, 41, 102, 119, and 87 days, respectively. Only longer DTE was associated with decreased mortality (hazard ratio, 0.720; 95% confidence interval, 0.536-0.965; p  = 0.028). Conclusion  DTI, SRT, RTD, SIT, and TTP do not significantly affect overall survival in patients with HNMM who undergo surgery and adjuvant radiation. Longer DTE is associated with improved survival in this population. Level of Evidence  4.

Single-arm study of camrelizumab plus apatinib for patients with advanced mucosal melanoma

BACKGROUND

Previous studies have suggested the potential synergistic antitumor activity when combining immune checkpoint inhibitors with anti-angiogenic agents in various solid tumors. We aimed to assess the efficacy and safety of camrelizumab (a humanized programmed cell death-1 antibody) plus apatinib (a vascular endothelial growth factor receptor tyrosine kinase inhibitor) for patients with advanced mucosal melanoma (MM), and explore-related biomarkers.

METHODS

We conducted a single-center, open-label, single-arm, phase II study. Patients with unresectable or recurrent/metastatic MM received camrelizumab and apatinib. The primary endpoint was the confirmed objective response rate (ORR).

RESULTS

Between April 2019 and June 2022, 32 patients were enrolled, with 50.0% previously received systemic therapy. Among 28 patients with evaluable response, the confirmed ORR was 42.9%, the disease control rate was 82.1%, and the median progression-free survival (PFS) was 8.05 months. The confirmed ORR was 42.9% (6/14) in both treatment-naïve and previously treated patients. Notably, treatment-naïve patients had a median PFS of 11.89 months, and those with prior treatment had a median PFS of 6.47 months. Grade 3 treatment-related adverse events were transaminase elevation, rash, hyperbilirubinemia, proteinuria, hypertension, thrombocytopenia, hand-foot syndrome and diarrhea. No treatment-related deaths were observed. Higher tumor mutation burden (TMB), increased T-cell receptor (TCR) diversity, and altered receptor tyrosine kinase (RTK)/RAS pathway correlated with better tumor response.

CONCLUSION

Camrelizumab plus apatinib provided promising antitumor activity with acceptable toxicity in patients with advanced MM. TMB, TCR diversity and RTK/RAS pathway genes were identified as potential predictive biomarkers and warrant further validation.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Registry, ChiCTR1900023277.

VEGF/VEGFR axis and its signaling in melanoma: Current knowledge toward therapeutic targeting agents and future perspectives

Melanoma is responsible for most skin cancer-associated deaths globally. The progression of melanoma is influenced by a number of pathogenic processes. Understanding the VEGF/VEGFR axis, which includes VEGF-A, PlGF, VEGF-B, VEGF-C, and VEGF-D and their receptors, VEGFR-1, VEGFR-2, and VEGFR-3, is of great importance in melanoma due to its crucial role in angiogenesis. This axis generates multifactorial and complex cellular signaling, engaging the MAPK/ERK, PI3K/AKT, PKC, PLC-γ, and FAK signaling pathways. Melanoma cell growth and proliferation, migration and metastasis, survival, and acquired resistance to therapy are influenced by this axis. The VEGF/VEGFR axis was extensively examined for their potential as diagnostic/prognostic biomarkers in melanoma patients and results showed that VEGF overexpression can be associated with unfavorable prognosis, higher level of tumor invasion and poor response to therapy. MicroRNAs linking to the VEGF/VEGFR axis were identified and, in this review, divided into two categories according to their functions, some of them promote melanoma angiogenesis (promotive group) and some restrict melanoma angiogenesis (protective group). In addition, the approach of treating melanoma by targeting the VEGF/VEGFR axis has garnered significant interest among researchers. These agents can be divided into two main groups: anti-VEGF and VEGFR inhibitors. These therapeutic options may be a prominent step along with the modern targeting and immune therapies for better coverage of pathological processes leading to melanoma progression and therapy resistance.

Comprehensive molecular findings in primary malignant melanoma of the esophagus: A multicenter study

Primary malignant melanoma of the esophagus (PMME) is an extremely rare but highly aggressive malignancy with a poor prognosis. Due to the scarcity of driver gene alterations, there is a need for more clinical data to comprehensively depict its molecular alterations. This study reviewed 26 PMME cases from three medical centers. Hybrid capture-based targeted sequencing of 295 and 1021 genes was performed in 14 and 12 cases, respectively. We found that PMME patients had a relatively low tumor mutation burden (median, 2.88 mutations per Mb) and were simultaneously accompanied by mutations in genes such as KIT (6/26, 23%), TP53 (6/26, 23%), SF3B1 (4/26, 15%), and NRAS (3/26, 12%). KIT, NRAS, and BRAF were mutually exclusive, and SF3B1 co-occurred with KIT mutation and amplification. The most common pathways affected were the mitogen-activated protein kinases and DNA damage response (DDR) pathways. Stage IV was a risk factor for both progression-free survival (hazard ratio [HR] = 5.14, 95% confidence interval [CI] = 1.32-19.91) and overall survival (OS), HR = 4.33, 95% CI = 1.22-15.30). Treatment with immune-checkpoint inhibitors (ICIs) was an independent factor for favorable OS (HR = 0.10, 95% CI = 0.01-0.91). Overall, PMME is a complex malignancy with diverse gene alterations, especially with harboring DDR alterations for potentially response from ICIs.

The treatment of advanced melanoma: Current approaches and new challenges

In recent years, advances in melanoma treatment have renewed patient hope. This comprehensive review emphasizes the evolving treatment landscape, particularly highlighting first-line strategies and the interplay between immune-checkpoint inhibitors (ICIs) and targeted therapies. Ipilimumab plus nivolumab has achieved the best median overall survival, exceeding 70 months. However, the introduction of new ICIs, like relatlimab, has added complexity to first-line therapy decisions. Our aim is to guide clinicians in making personalized treatment decisions. Various features, including brain metastases, PD-L1 expression, BRAF mutation, performance status, and prior adjuvant therapy, significantly impact the direction of advanced melanoma treatment. We also provide the latest insights into the treatment of rare melanoma subtypes, such as uveal melanoma, where tebentafusp has shown promising improvements in overall survival for metastatic uveal melanoma patients. This review provides invaluable insights for clinicians, enabling informed treatment choices and deepening our understanding of the multifaceted challenges associated with advanced melanoma management.

Recent advances in tyrosine kinase inhibitors VEGFR 1-3 for the treatment of advanced metastatic melanoma

INTRODUCTION

Increasing evidence from preclinical and clinical studies suggests the role of vascular endothelial growth factor (VEGF) signaling in melanoma progression, response to therapy, and overall survival. Moreover, the discovery of the potential involvement of the VEGF pathway in resistance to immunotherapy has led to new clinical trials with VEGFR inhibitors.

AREAS COVERED

We have reviewed recent literature, mainly published within the last 5 years, on VEGFR-targeted treatments for advanced melanoma, including mucosal, acral, and uveal melanoma. The VEGFR inhibitors were used as a single therapy or combined with either immunotherapy or chemotherapy, and they were employed in treatment for KIT-mutated cutaneous melanoma and for patients with brain metastases.

EXPERT OPINION

Trials involving monotherapy have been unsuccessful in demonstrating meaningful efficacy. Despite some activity, the combination of VEGFR-targeting tyrosine kinase inhibitors (TKIs) with immune checkpoint inhibitors (ICI) in patients with ICI-resistant melanoma, the combination did not significantly improve outcomes compared to anti-PD-1 monotherapy in the first-line settings. On the contrary, some patients with mucosal, acral or KIT-mutant melanoma may benefit from TKI-based therapies. Further studies focused on biomarker discovery and randomized trials are necessary to better understand the role of VEGFR1-3 as a therapeutic target in melanoma.

New clinical trial design in precision medicine: discovery, development and direction

In the era of precision medicine, it has been increasingly recognized that individuals with a certain disease are complex and different from each other. Due to the underestimation of the significant heterogeneity across participants in traditional "one-size-fits-all" trials, patient-centered trials that could provide optimal therapy customization to individuals with specific biomarkers were developed including the basket, umbrella, and platform trial designs under the master protocol framework. In recent years, the successive FDA approval of indications based on biomarker-guided master protocol designs has demonstrated that these new clinical trials are ushering in tremendous opportunities. Despite the rapid increase in the number of basket, umbrella, and platform trials, the current clinical and research understanding of these new trial designs, as compared with traditional trial designs, remains limited. The majority of the research focuses on methodologies, and there is a lack of in-depth insight concerning the underlying biological logic of these new clinical trial designs. Therefore, we provide this comprehensive review of the discovery and development of basket, umbrella, and platform trials and their underlying logic from the perspective of precision medicine. Meanwhile, we discuss future directions on the potential development of these new clinical design in view of the "Precision Pro", "Dynamic Precision", and "Intelligent Precision". This review would assist trial-related researchers to enhance the innovation and feasibility of clinical trial designs by expounding the underlying logic, which be essential to accelerate the progression of precision medicine.

Optimal strategy in managing advanced melanoma

The advent of immune checkpoint inhibitors and combination therapy with BRAF inhibitors and MEK inhibitors has dramatically improved the prognosis of advanced melanoma. However, since acral melanoma and mucosal melanoma, which are rare in Western countries but are major subtypes of melanoma in East Asia, including Japan, have a low frequency of BRAF mutations, there are currently no treatment options other than immune checkpoint inhibitors in most such cases. Furthermore, owing to a lower tumor mutation burden, immune checkpoint inhibitors are less effective in acral and mucosal melanoma than in cutaneous melanoma. The aim of this review was to summarize the current status and future prospects for the treatment of advanced melanoma, comparing cutaneous melanoma, acral melanoma, and mucosal melanoma.

Primary Mucosal Melanoma: Clinical Experience from a Single Italian Center

(1) Background: Mucosal melanoma (MM) is a rare tumor, accounting for about 1% of all diagnosed melanomas. The etiology and pathogenesis of this tumor are unknown. It is characterized by an aggressive phenotype with poor prognosis and a low response rate to approved treatments. (2) Methods: We retrospectively analyzed the clinical features, treatments and outcomes of patients diagnosed with MM from different sub-sites (head and neck, gynecological and gastro-intestinal region) between 2013 and 2023 at our Institute. Survival times were estimated with the Kaplan-Meier method. Multivariate Cox regression was used to test the independence of significant factors in univariate analysis. (3) Results: Twenty-five patients were included in this study; the disease was equally distributed among females and males. The median age at diagnosis was 74 years old. The majority had MM originating from the head and neck (56%), particularly from the nasal cavity. BRAF V600 mutations were detected in 16% of the study population, limited to gastro-intestinal and gynecological MM. At diagnosis, at least half the patients (52%) had the disease located also at distant sites. The median overall survival (OS) in the whole study population was 22 months, with a longer OS for patients diagnosed at an early stage (38 months, p < 0.001). Longer OSs were reported for head and neck MM compared to other anatomic regions (0.06). Surgery of the primary tumor and radiotherapy were performed in 64% and 36% of the study population, respectively. Radiotherapy was performed only in head and neck MM. At multivariate analysis, the single factor that showed a reduced hazard ratio for death was radiotherapy. (4) Conclusions: The overall survival of MM from different sub-sites treated at our Italian Institution was 22 months, with better outcomes for early-stage disease and head and neck MM. Performing radiotherapy may have a protective effect on OS for head and neck MM. New treatment strategies are urgently needed to improve the outcome in this disease.

Proceedings from the Melanoma Research Foundation Mucosal Melanoma Meeting (December 16, 2022, New York, USA)

Mucosal melanoma remains a rare cancer with high mortality and a paucity of therapeutic options. This is due in significant part to its low incidence leading to limited patient access to expert care and downstream clinical/basic science data for research interrogation. Clinical challenges such as delayed and at times inaccurate diagnoses, and lack of consensus tumor staging have added to the suboptimal outcomes for these patients. Clinical trials, while promising, have been difficult to activate and accrue. While individual institutions and investigators have attempted to seek solutions to such problems, international, national, and local partnership may provide the keys to more efficient and innovative paths forward. Furthermore, a mucosal melanoma coalition would provide a potential network for patients and caregivers to seek expert opinion and advice. The Melanoma Research Foundation Mucosal Melanoma Meeting (December 16, 2022, New York, USA) highlighted the current clinical challenges faced by patients, providers, and scientists, identified current and future clinical trial investigations in this rare disease space, and aimed to increase national and international collaboration among the mucosal melanoma community in an effort to improve patient outcomes. The included proceedings highlight the clinical challenges of mucosal melanoma, global clinical trial experience, basic science advances in mucosal melanoma, and future directions, including the creation of shared rare tumor registries and enhanced collaborations.

Decoding the metastatic potential and optimal postoperative adjuvant therapy of melanoma based on metastasis score

Metastasis is a formidable challenge in the prognosis of melanoma. Accurately predicting the metastatic potential of non-metastatic melanoma (NMM) and determining effective postoperative adjuvant treatments for inhibiting metastasis remain uncertain. In this study, we conducted comprehensive analyses of melanoma metastases using bulk and single-cell RNA sequencing data, enabling the construction of a metastasis score (MET score) through diverse machine-learning algorithms. The reliability and robustness of the MET score were validated using various in vitro assays and in vivo models. Our findings revealed a distinct molecular landscape in metastatic melanoma characterized by the enrichment of metastasis-related pathways, intricate cell-cell communication, and heightened infiltration of pro-angiogenic tumor-associated macrophages compared to NMM. Importantly, patients in the high MET score group exhibited poorer prognoses and an immunosuppressive microenvironment, featuring increased infiltration of regulatory T cells and decreased infiltration of CD8+ T cells, compared to the low MET score patient group. Expression of PD-1 was markedly higher in patients with low MET scores. Anti-PD-1 (aPD-1) therapy profoundly affected antitumor immunity activation and metastasis inhibition in these patients. In summary, our study demonstrates the effectiveness of the MET score in predicting melanoma metastatic potential. For patients with low MET scores, aPD-1 therapy may be a potential treatment strategy to inhibit metastasis. Patients with high MET scores may benefit from combination therapies.

Immunotherapy in Melanoma: Recent Advancements and Future Directions

Immune checkpoint inhibition has fundamentally altered the treatment paradigm of resectable and unresectable melanoma, resulting in dramatic improvements in patient outcomes. With these advances, the five-year overall survival in patients with newly diagnosed unresectable disease has eclipsed 50%. Ongoing research is focused on improving outcomes further, with a considerable emphasis on preventing de novo and acquired resistance and personalizing therapeutic options. Here, we review the ongoing advancements in the treatment of malignant melanoma, focusing on novel combination strategies that aim to build upon the successes of the last decade.

SALVO: Single-Arm Trial of Ipilimumab and Nivolumab as Adjuvant Therapy for Resected Mucosal Melanoma

PURPOSE

Mucosal melanoma is a rare, aggressive form of melanoma with extremely high recurrence rates despite definitive surgical resection with curative intent. Currently there is no consensus on adjuvant therapy. Data on checkpoint inhibitors for adjuvant therapy are lacking.

PATIENTS AND METHODS

We performed a single-arm, multicenter clinical trial using "flip dose" ipilimumab (1 mg/kg q3w × 4 cycles), and nivolumab (3 mg/kg q3w × 4 cycles), then nivolumab 480 mg q4w × 11 cycles to complete a year of adjuvant therapy. Participants must have had R0/R1 resection ≤90 days before registration, no prior systemic therapy (adjuvant radiotherapy allowed), ECOG 0/1, and no uncontrolled autoimmune disease or other invasive cancer. Patients were recruited through the Midwest Melanoma Partnership/Hoosier Oncology Network.

RESULTS

From September 2017 to August 2021, 35 patients were enrolled. Of these, 29 (83%) had R0 resections, and 7 (20%) received adjuvant radiotherapy. Median age was 67 years, 21 (60.0%) female. Recurrence-free survival (RFS) rates at 1 and 2 years were 50% [95% confidence interval (CI), 31%-66%] and 37% (95% CI, 19%-55%), respectively. Overall survival rates at 1 and 2 years were 87% (95% CI, 68%-95%) and 68% (95% CI, 46%-83%), respectively. Median RFS was 10.3 months (95% CI, 5.7-25.8). Most common grade 3 toxicities were diarrhea (14%), hypertension (14%), and hyponatremia (11%), with no grade 4/5 toxicities.

CONCLUSIONS

Flip-dose ipilimumab and nivolumab after resection of mucosal melanoma is associated with outcomes improved over that of surgical resection alone. Long-term follow-up, subgroup analyses and correlative studies are ongoing.

Nuclear PD-L1 promotes EGR1-mediated angiogenesis and accelerates tumorigenesis

Targeting programmed cell death protein ligand 1 (PD-L1) remains one of the most essential immunotherapies in cancer^1,2. PD-L1 has been detected in the nucleus in multiple malignancies, playing an oncogenic role independent of immune checkpoint regulation^3-5. Howbeit, the regulatory function of nuclear PD-L1 (nPD-L1) remains to be fully understood. Here, we report that nPD-L1 is an endogenous accelerator for cancer angiogenesis. First, we found that an abundant proportion of PD-L1 was distributed within the nucleus of uveal melanoma samples, which is associated with an unfavorable outcome. Moreover, the capacity of promoting angiogenesis was largely attenuated in the nPD-L1-deficient cells both in vivo and in vitro. Mechanistically, nPD-L1 facilitates p-STAT3 binding to the promoter of early growth response-1 (EGR1), resulting in the activation of EGR1-mediated angiogenesis. Therapeutically, the inhibition of histone deacetylase 2 restores the normal acetylation level of PD-L1, blocking its nuclear translocation and thereby attenuating tumor angiogenesis. Conclusively, we reveal that nPD-L1 promotes angiogenesis in malignancies, and provide a novel anti-vascularization strategy through blocking aberrant PD-L1 nuclear translocation for tumor therapy.

Immune checkpoint inhibitor-based therapy for advanced acral and mucosal melanoma

Acral melanoma (AM) and mucosal melanomas (MM) are rare clinical subtypes of melanoma. AM and MM are etiologically, biologically, and molecularly distinct from cutaneous melanoma (CM). Despite the recent development of immune checkpoint inhibitors (ICIs) for the treatment of advanced CMs, the true therapeutic efficacy of ICIs for these rare subtypes remains unclear. Since these subtypes are rare, especially in the Caucasian population, their biological features and corresponding novel therapies are underexplored than those of CM. Even in the larger phase III clinical trials for ICIs, the sample size of patients with AM and MM is limited. Consequently, establishment of standard of care for advanced AM and MM has been challenging. This review covers current update and overview on clinical efficacy of ICIs and ICI-based therapy for advanced AM and MM, based mainly on the reported clinical trials, prospective observational studies, and retrospective studies, to provide a better understanding of the current landscape of this field. In addition, we discuss the future direction of treatment for those rare clinical subtypes, focusing on issues relevant to dermatology and medical oncology.

Current Trends in Mucosal Melanomas: An Overview

Primary mucosal melanomas (MMs) are uncommon tumors originating from melanocytes located in the mucous membranes at various anatomic sites within the body. MM significantly differs from cutaneous melanoma (CM) regarding epidemiology, genetic profile, clinical presentation, and response to therapies. Despite these differences, that have important implications for both disease diagnosis and prognosis, MMs are usually treated in the same way as CM but exhibit a lower response rate to immunotherapy leading to a poorer survival rate. Furthermore, a high inter-patient variability can be observed in relation to therapeutic response. Recently, novel "omics" techniques have evidenced that MM lesions have different genomic, molecular, and metabolic landscapes as compared with CM lesions, thus explaining the heterogeneity of the response. Such specific molecular aspects might be useful to identify new biomarkers aimed at improving the diagnosis and selection of MM patients who could benefit from immunotherapy or targeted therapy. In this review, we have focused on relevant molecular and clinical advancements for the different MM subtypes in order to describe the updated knowledge relating to main diagnostic, clinical, and therapeutic implications as well as to provide hints on likely future directions.

Shaping the Future of Immunotherapy Targets and Biomarkers in Melanoma and Non-Melanoma Cutaneous Cancers

Recent advances in treating cutaneous melanoma have resulted in impressive patient survival gains. Refinement of disease staging and accurate patient risk classification have significantly improved our prognostic knowledge and ability to accurately stratify treatment. Undoubtedly, the most important step towards optimizing patient outcomes has been the advent of cancer immunotherapy, in the form of immune checkpoint inhibition (ICI). Immunotherapy has established its cardinal role in the management of both early and late-stage melanoma. Through leveraging outcomes in melanoma, immunotherapy has also extended its benefit to other types of skin cancers. In this review, we endeavor to summarize the current role of immunotherapy in melanoma and non-melanoma skin cancers, highlight the most pertinent immunotherapy-related molecular biomarkers, and lastly, shed light on future research directions.

The efficacies and biomarker investigations of antiangiogenic agents and PD-1 inhibitors for metastatic soft tissue sarcoma: A multicenter retrospective study

Objective

To investigate the efficacy and safety of antiangiogenesis-immunotherapy in patients with advanced STS in China, and to explore the potential factors of prognosis.

Patients and Methods

This retrospective study was conducted at three hospitals in China, and the patients with metastatic STS who were ineligible for or declined anthracycline-based chemotherapy received antiangiogenic agents (anlotinib or apatinib) plus programmed death-1 (PD-1) inhibitors (camrelizumab or sintilimab) between June 2019 and May 2022. The primary endpoint was progression-free survival rate at 6 months (6-month PFSR), and the secondary endpoints were objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS) and toxicity. Biomarkers that might affect the prognosis were explored.

Results

Thirty-nine patients were included: five patients with alveolar soft tissue sarcoma (ASPS) and 34 with non-ASPS. With a median follow-up of 18.2 months, the 6-month PFSR was 51.3%, with the ORR of 20.5% and DCR of 76.9%. The median PFS and OS were 7.0 months and 17.2 months. The 6-month PFSR for patients with ASPS and non-ASPS was 80.0% and 47.1%, respectively. The most common adverse events were hypothyroidism (56.4%), followed by fatigue (46.2%), and hypertriglyceridemia (43.6%). No treatment-related deaths were observed. Patients with low baseline NLR (NLR < 4) had better 6-month PFSR than those with high NLR (NLR ≥ 4) (82.4% vs. 31.6%).

Conclusion

Antiangiogenic agents plus PD-1 inhibitors showed acceptable toxicity and promising efficacy in patients with advanced STS, especially patients with ASPS, and a low NLR might serve as a reliable biomarker for 6-month PFSR, PFS, and OS. It provides a reference for randomized controlled trials.

Nivolumab-induced capillary leak syndrome associated with chylothorax in a melanoma patient: A case report and review of the literature

Introduction

Adverse events (AEs) of immune checkpoint inhibitors (ICIs) are frequent and mainly due to an overactivity of the immune system leading to excessive inflammatory responses (immune-related AE) that can affect any organ of the body. Beside the most frequent AEs, there are rare AEs whose diagnosis and treatment can be challenging. We report here a singular case of capillary leak syndrome (CLS) associated with chylothorax occurring in a patient who has been treated with adjuvant nivolumab (anti-PD1) for resected AJCC stage IIB primary melanoma.

Case presentation

A 43-year-old woman was diagnosed with a nodular stage IIB melanoma of her left thigh, according to the AJCC 8th edition (T3bN0M0). The woman was treated with adjuvant nivolumab. She stopped the treatment after 4 infusions due to thrombopenia. Three months later, she developed facial and leg edema and ascites due to capillary leak syndrome. The CLS was associated with chylothorax and elevated vascular endothelial growth factor. The patient was initially treated with several pleural puncturing and steroids. CLS and chylothorax progressively decreased with intravenous immunoglobulins and fat-free diet without recurrence of melanoma at one-year follow-up.

Conclusion

CLS is a rare and potentially life-threatening AE of ICIs such as anti-PD1. This AE may be associated with chylothorax probably related to lymphatic permeability induced by anti-PD1.

Melanoma Tumour Vascularization and Tissue-Resident Endothelial Progenitor Cells

The aggressiveness of solid cancers, such as melanoma, relies on their metastatic potential. It has become evident that this key cause of mortality is largely conferred by the tumour-associated stromal cells, especially endothelial cells. In addition to their essential role in the formation of the tumour vasculature, endothelial cells significantly contribute to the establishment of the tumour microenvironment, thus enabling the dissemination of cancer cells. Melanoma tumour vascularization occurs through diverse biological processes. Vasculogenesis is the formation of de novo blood vessels from endothelial progenitor cells (EPCs), and recent research has shown the role of EPCs in melanoma tumour vascularization. A more detailed understanding of the complex role of EPCs and how they contribute to the abnormal vessel structures in tumours is of importance. Moreover, anti-angiogenic drugs have a limited effect on melanoma tumour vascularization, and the role of these drugs on EPCs remains to be clarified. Overall, targeting cancer vasculature remains a challenge, and the role of anti-angiogenic drugs and combination therapies in melanoma, a focus of this review, is an area of extensive exploration.