Conjunctival melanoma: New insights in tumour genetics and immunology, leading to new therapeutic options

Pediatric conjunctival melanoma: A comprehensive case report and literature review

Purpose

This case report aims to present a rare instance of conjunctival melanoma in a 5-year-old patient and contribute to the limited body of knowledge on pediatric conjunctival melanoma. The purpose is to understand the characteristics, diagnosis, and management of this uncommon malignancy in young individuals.

Observations

The case describes a 5-year-old female with a progressively growing pigmented conjunctival lesion. The lesion was observed to be located on the temporal conjunctiva of the right eye and displayed distinctive features, including feeder vessels. Imaging revealed specific dimensions of the lesion and ruled out deeper invasions. Histopathological examination revealed architectural and cytologic atypia, positive immunohistochemical staining for HMB-45, and a Ki67 proliferation index of 20 %, confirming the diagnosis of conjunctival melanoma.

Conclusions

Conjunctival melanoma, an uncommon malignancy even more so in pediatric patients, typically presents with pigmented growths and feeder vessels. This case underscores the need for thorough diagnosis and early intervention, as conjunctival melanoma can lead to devastating outcomes. The rarity of such cases limits our understanding of their etiology and progression. This case contributes to the literature on pediatric conjunctival melanoma and reinforces the importance of vigilance in detecting and managing ocular pigmented lesions in children.

Single-cell sequencing depicts tumor architecture and empowers clinical decision in metastatic conjunctival melanoma

Conjunctival melanoma (CoM) is a potentially devastating tumor that can lead to distant metastasis. Despite various therapeutic strategies for distant metastatic CoM, the clinical outcomes remain unfavorable. Herein, we performed single-cell RNA sequencing (scRNA-seq) of 47,017 cells obtained from normal conjunctival samples (n = 3) and conjunctival melanomas (n = 7). Notably, we noticed a higher abundance of cancer-associated fibroblasts (CAFs) in tumor microenvironment (TME), correlated with enhanced angiogenic capacity and increased VEGFR expression in distal metastatic CoM. Additionally, we observed a significant decrease in the proportion of total CD8+ T cells and an increase in the proportion of naive CD8+ T cells, contributing to a relatively quiescent immunological environment in distal metastatic CoM. These findings were confirmed through the analyses of 70,303 single-cell transcriptomes of 7 individual CoM samples, as well as spatially resolved proteomes of an additional 10 samples of CoMs. Due to the increase of VEGFR-mediated angiogenesis and a less active T cell environment in distal metastatic CoMs, a clinical trial (ChiCTR2100045061) has been initiated to evaluate the efficacy of VEGFR blockade in combination with anti-PD1 therapy for patients with distant metastatic CoM, showing promising tumor-inhibitory effects. In conclusion, our study uncovered the landscape and heterogeneity of the TME during CoM tumorigenesis and progression, empowering clinical decisions in the management of distal metastatic CoM. To our knowledge, this is the initial exploration to translate scRNA-seq analysis to a clinical trial dealing with cancer, providing a novel concept by accommodating scRNA-seq data in cancer therapy.

Lactate secreted by glycolytic conjunctival melanoma cells attracts and polarizes macrophages to drive angiogenesis in zebrafish xenografts

Conjunctival melanoma (CoM) is a rare but potentially lethal cancer of the eye, with limited therapeutic option for metastases. A better understanding how primary CoM disseminate to form metastases is urgently needed in order to develop novel therapies. Previous studies indicated that primary CoM tumors express Vascular Endothelial Growth Factor (VEGF) and may recruit pro-tumorigenic M2-like macrophages. However, due to a lack of proper models, the expected role of angiogenesis in the metastatic dissemination of CoM is still unknown. We show that cells derived from two CoM cell lines induce a strong angiogenic response when xenografted in zebrafish larvae. CoM cells are highly glycolytic and secrete lactate, which recruits and polarizes human and zebrafish macrophages towards a M2-like phenotype. These macrophages elevate the levels of proangiogenic factors such as VEGF, TGF-β, and IL-10 in the tumor microenvironment to induce an angiogenic response towards the engrafted CoM cells in vivo. Chemical ablation of zebrafish macrophages or inhibition of glycolysis in CoM cells terminates this response, suggesting that attraction of lactate-dependent macrophages into engrafted CoM cells drives angiogenesis and serves as a possible dissemination mechanism for glycolytic CoM cells.

Personalized treatment concepts in extraocular cancer

Background

The periocular skin is neoplasms-prone to various benign and malignant. Periocular malignancies are more aggressive and challenging to cure and repair than those in other skin areas. In recent decades, immunotherapy has significantly advanced oncology, allowing the autoimmune system to target and destroy malignant cells. Skin malignancies, especially periocular tumors, are particularly sensitive to immunotherapy. This technique has dramatically impacted the successful treatment of challenging tumors.

Main text

Extraocular cancers, including eyelid (basal cell carcinoma, squamous cell carcinoma, melanoma, merkel cell carcinoma), conjunctival tumors (conjunctival melanoma, ocular surface squamous neoplasia) and other rare tumors, are unique and challenging clinical situations. Several genetic alterations associated with the pathogenesis of these diseases have been identified, and molecular mechanism are essential for the development of the immunotherapy agents, such as Hedgehog pathway inhibitors (vismodegib and sonidegib) for basal cell carcinoma, BRAF/MEK inhibitors (vemurafenib, dabrafenib, and encorafenib) for melanoma, and immune checkpoint inhibitors (Avelumab, pembrolizumab) for Merkel cell carcinoma.

Conclusions

The optimal treatment for periocular skin cancer depends on the type and size of the tumor and whether it involves orbital and adnexal structures. Adjuvant and neoadjuvant therapy with chemotherapy-targeted therapies and immune checkpoint inhibitors should be considered based on tumor type, tumor molecular profile, expected response rate, and candidacy for systemic treatment.

Ultrasound-enhanced nano catalyst with ferroptosis-apoptosis combined anticancer strategy for metastatic uveal melanoma

Uveal melanoma is the most common primary ocular tumor owing to its highly invasive and metastatic characteristics. Currently, standard clinical treatment has an unsatisfied curative effect due to the lack of an effective approach to inhibit the tumor metastasis. Therefore, it is necessary to develop a new strategy that can both restraint local tumors and suppress the ocular tumor metastasis. Herein, we developed ultrasound-responsive nanoparticles (FeP NPs) that can both hinder the growth of in situ ocular tumor and prevent the tumor metastasis through the ferroptosis-apoptosis combined-anticancer strategy. The FeP NPs were assembling by stimulating gallic acid-Fe (III) and paclitaxel, then could be internalized into tumor cells under the cooperative effect of ultrasound, which further activates the intracellular Fenton reaction and generates high reactive oxygen species levels, ultimately leading to mitochondrial damage, lipid per-oxidation, and apoptosis. The FeP NPs can efficiently inhibit the tumor growth in an orthotopic uveal melanoma model. More importantly, the level of the promoting-metastatic factor nerve growth factor receptor (NGFR) secreted by cancer cells is significantly reduced, further limits cancer metastasis to the cervical lymph node and finally inhibits lung metastasis of uveal melanoma. We believe that these designed ultrasound-enhanced nanoparticles possess potential clinical application for preventing the regeneration and metastasis of uveal melanoma.

Targeted therapy in ophthalmic oncology: The current status

There have been rapid advancements in the field of ocular oncology for the diagnosis and management of intraocular, adnexal, and orbital tumors. Targeted therapy is in the forefront of medical research in all fields including ocular oncology. Targeted therapy include drugs that target specific genetic mutations, pathways or proteins involved in the development of cancer. In contrast to traditionally used chemotherapy, drugs used in targeted therapy are highly specific for tumor cells and preserve the function of normal cells. This review aims to familiarize ophthalmologists with the drugs that are currently approved or undergoing clinical trials for use in ocular oncology. Targeted therapy is particularly useful for locally advanced or metastatic tumors, including but not limited to eyelid and periocular basal cell carcinoma, periocular cutaneous and conjunctival squamous cell carcinoma, ocular adnexal lymphoma, conjunctival melanoma, and uveal melanoma. The results are promising with improved survival outcomes and better tolerability than chemotherapeutic drugs.

Treatment response and recurrence of conjunctival melanoma with orbital invasion treated with immune checkpoint inhibitors: case report and literature review

INTRODUCTION

Conjunctival melanoma (CM) has genetic characteristics that are similar to primary cutaneous melanoma (PCM). The management of advanced CM with orbital metastasis was limited until the adoption of novel immunotherapy agents that significantly improved the survival of metastatic PCM.

PURPOSE

To review and compare the immune checkpoint inhibitor (ICI) treatment response in cases reported in the English literature with orbital involvement secondary to CM versus PCM. In addition, we report a case of local recurrence of CM in a young female after successful treatment with ICI.

METHODS

In addition to reviewing the chart of one patient who presented to our clinic, we conducted a comprehensive literature review to identify CM cases and cases with orbital metastasis secondary to advanced CM and PCM. Outcomes included patient demographics, response to ICI, and associated adverse effects.

RESULTS

There were ten cases with orbital involvement, four were secondary to CM, and six were metastasis from PCM. Orbital metastasis from PCM regressed following treatment with ICI agents, whereas those secondary to CM resolved completely. There were 19 cases of CM without orbital invasion. Of the 29 cases identified, complete resolution of ocular melanoma was achieved in 15 patients, representing 52% of the cases collectively, and none of them reported recurrence except in our case.

CONCLUSION

CM with orbital invasion responds well to ICIs, with manageable toxic effects. Despite the complete resolution, close observation is needed as the recurrence risk remains.

Revolutionizing ocular cancer management: a narrative review on exploring the potential role of ChatGPT

This paper pioneers the exploration of ocular cancer, and its management with the help of Artificial Intelligence (AI) technology. Existing literature presents a significant increase in new eye cancer cases in 2023, experiencing a higher incidence rate. Extensive research was conducted using online databases such as PubMed, ACM Digital Library, ScienceDirect, and Springer. To conduct this review, Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines are used. Of the collected 62 studies, only 20 documents met the inclusion criteria. The review study identifies seven ocular cancer types. Important challenges associated with ocular cancer are highlighted, including limited awareness about eye cancer, restricted healthcare access, financial barriers, and insufficient infrastructure support. Financial barriers is one of the widely examined ocular cancer challenges in the literature. The potential role and limitations of ChatGPT are discussed, emphasizing its usefulness in providing general information to physicians, noting its inability to deliver up-to-date information. The paper concludes by presenting the potential future applications of ChatGPT to advance research on ocular cancer globally.

Incidence and Mortality of Conjunctival Melanoma in Australia (1982 to 2014)

Purpose

The purpose of this study was to estimate the incidence and mortality of conjunctival melanoma in Australia from 1982 to 2014.

Methods

De-identified unit data for all cases of ocular melanoma were extracted from the Australian Cancer Database from 1982 to 2014. Conjunctival melanoma cases were extracted, and the incidence and mortality were analyzed. Incidence rates were age-standardized against the 2001 Australian Standard Population. Mortality was assessed using log-rank and Cox regression.

Results

From 1982 to 2014, there were 299 cases of conjunctival melanoma. The age-standardized incidence rate was 0.48 (95% confidence interval [CI] = 0.41 to 0.54) per million per year. Women (0.52, 95% CI = 0.42 to 0.62) had a higher incidence than men (0.42, 95% CI = 0.33 to 0.51). The incidence of conjunctival melanoma increased in men (+1.46%) and significantly women (+1.41%, P = 0.023) over the study period. The mean 5-, 10-, and 15-year disease-specific survival were 90%, 82%, and 80%, respectively, during the 33-year interval. Comparisons of survival among age, sex, and state revealed no significant differences when tested using log-rank or Cox regression.

Conclusions

In conclusion, we found an increase in the rate of conjunctival melanoma diagnoses in Australia from 1982 to 2014. Over the same period, disease survival remained unchanged at a mean of 90%.

Targeting histone deacetylase suppresses tumor growth through eliciting METTL14-modified m6 A RNA methylation in ocular melanoma

BACKGROUND

Diversified histone deacetylation inhibitors (HDACis) have demonstrated encouraging outcomes in multiple malignancies. N6-methyladenine (m6 A) is the most prevalent messenger RNA modification that plays an essential role in the regulation of tumorigenesis. Howbeit, an in-depth understanding of the crosstalk between histone acetylation and m6 A RNA modifications remains enigmatic. This study aimed to explore the role of histone acetylation and m6 A modifications in the regulation of tumorigenesis of ocular melanoma.

METHODS

Histone modification inhibitor screening was used to explore the effects of HDACis on ocular melanoma cells. Dot blot assay was used to detect the global m6 A RNA modification level. Multi-omics assays, including RNA-sequencing, cleavage under targets and tagmentation, single-cell sequencing, methylated RNA immunoprecipitation-sequencing (meRIP-seq), and m6 A individual nucleotide resolution cross-linking and immunoprecipitation-sequencing (miCLIP-seq), were performed to reveal the mechanisms of HDACis on methyltransferase-like 14 (METTL14) and FAT tumor suppressor homolog 4 (FAT4) in ocular melanoma. Quantitative real-time polymerase chain reaction (qPCR), western blotting, and immunofluorescent staining were applied to detect the expression of METTL14 and FAT4 in ocular melanoma cells and tissues. Cell models and orthotopic xenograft models were established to determine the roles of METTL14 and FAT4 in the growth of ocular melanoma. RNA-binding protein immunoprecipitation-qPCR, meRIP-seq, miCLIP-seq, and RNA stability assay were adopted to investigate the mechanism by which m6 A levels of FAT4 were affected.

RESULTS

First, we found that ocular melanoma cells presented vulnerability towards HDACis. HDACis triggered the elevation of m6 A RNA modification in ocular melanoma. Further studies revealed that METTL14 served as a downstream candidate for HDACis. METTL14 was silenced by the hypo-histone acetylation status, whereas HDACi restored the normal histone acetylation level of METTL14, thereby inducing its expression. Subsequently, METTL14 served as a tumor suppressor by promoting the expression of FAT4, a tumor suppressor, in a m6 A-YTH N6-methyladenosine RNA-binding protein 1-dependent manner. Taken together, we found that HDACi restored the histone acetylation level of METTL14 and subsequently elicited METTL14-mediated m6 A modification in tumorigenesis.

CONCLUSIONS

These results demonstrate that HDACis exert anti-cancer effects by orchestrating m6 A modification, which unveiling a "histone-RNA crosstalk" of the HDAC/METTL14/FAT4 epigenetic cascade in ocular melanoma.

Neoadjuvant Immune Checkpoint Inhibition in Metastatic Conjunctival Melanoma

The development of immune checkpoint inhibitors (ICI) has transformed the treatment of advanced-stage cutaneous melanoma; however, most trials did not include patients with conjunctival melanoma. Herein the authors describe a patient with recurrent conjunctival melanoma who developed locally advanced, b-raf and v-raf murine sarcoma viral oncogene homolog B1-negative melanoma in her nasal cavity and extensive, metabolically active, bilateral lymphadenopathy in her thorax. Her nasal mass measured 4.3 × 1.7 cm and was determined to be unresectable. She was treated with 4 cycles of combination ipilimumab and nivolumab therapy followed by maintenance nivolumab. She experienced a dramatic treatment response with a reduction in the size of her nasal mass to 3.0 × 1.1 cm and a complete resolution of her adenopathy. She then underwent complete surgical resection of her residual mass (approximately 75% of her original tumor size) and remains melanoma-free at 1 year of follow-up. Given the underlying genetic similarities of conjunctival melanoma to cutaneous melanoma, providers should consider the use of neoadjuvant immune checkpoint inhibitors for patients with locally advanced or limited metastatic disease.

Genetic Aspects of Conjunctival Melanoma: A Review

Conjunctival melanoma (CM) is a rare but aggressive cancer. Over the past decade, molecular studies using rapidly advancing technologies have increasingly improved our understanding of CM genetics. CMs are mainly characterized by dysregulated MAPK and PI3K/AKT/mTOR pathways, driven by commonly mutated (BRAF, NRAS, NF1) or less commonly mutated (KIT, PTEN) genes. Another group of genes frequently mutated in CMs include TERT and ATRX, with known roles in telomere maintenance and chromatin remodeling/epigenetic regulation. Uveal melanoma-related genes (BAP1, SF3B1, GNAQ/11) can also be mutated in CMs, albeit infrequently. Additional CM-related mutated genes have increasingly been identified using more comprehensive genetic analyses, awaiting further confirmation in additional/larger studies. As a tumor arising in a partly sun-exposed mucosal tissue, CM exhibits a distinct genomic profile, including the frequent presence of an ultraviolet (UV) signature (and high mutational load) and also the common occurrence of large structural variations (distributed across the genome) in addition to specific gene mutations. The knowledge gained from CM genetic studies to date has led to new therapeutic avenues, including the use of targeted and/or immuno-therapies with promising outcomes in several cases. Accordingly, the implementation of tumor genetic testing into the routine clinical care of CM patients holds promise to further improve and personalize their treatments. Likewise, a growing knowledge of poor prognosis-associated genetic changes in CMs (NRAS, TERT, and uveal melanoma signature mutations and chromosome 10q deletions) may ultimately guide future strategies for prognostic testing to further improve clinical outcomes (by tailoring surveillance and considering prophylactic treatments in patients with high-risk primary tumors).

Genetic predisposition to ocular surface disorders and opportunities for gene-based therapies

The ocular surface, comprised of the corneal and conjunctival epithelium, innervation system, immune components, and tear-film apparatus, plays a key role in ocular integrity as well as comfort and vision. Gene defects may result in congenital ocular or systemic disorders with prominent ocular surface involvement. Examples include epithelial corneal dystrophies, aniridia, ectrodactyly-ectodermal dysplasia-clefting (EEC) syndrome, xeroderma pigmentosum (XP), and hereditary sensory and autonomic neuropathy. In addition, genetic factors may interact with environmental risk factors in the development of several multifactorial ocular surface disorders (OSDs) such as autoimmune disorders, allergies, neoplasms, and dry eye disease. Advanced gene-based technologies have already been introduced in disease modelling and proof-of-concept gene therapies for monogenic OSDs. For instance, patient-derived induced pluripotent stem cells have been used for modelling aniridia-associated keratopathy (AAK), XP, and EEC syndrome. Moreover, CRISPR/Cas9 genome editing has been used for disease modelling and/or gene therapy for AAK and Meesmann's epithelial corneal dystrophy. A better understanding of the role of genetic factors in OSDs may be helpful in designing personalized disease models and treatment approaches. Gene-based approaches in monogenic OSDs and genetic predisposition to multifactorial OSDs such as immune-mediated disorders and neoplasms with known or possible genetic risk factors has been seldom reviewed. In this narrative review, we discuss the role of genetic factors in monogenic and multifactorial OSDs and potential opportunities for gene therapy.

Targeting β-catenin using XAV939 nanoparticle promotes immunogenic cell death and suppresses conjunctival melanoma progression

Many tumors dysregulate Wnt/β-catenin pathway to promote stem-cell-like phenotype, tumorigenesis, immunosuppression, and resistance to targeted cancer immunotherapies. Therefore, targeting this pathway is a promising therapeutic approach to suppress tumor progression and elicit robust anti-tumor immunity. In this study, using a nanoparticle formulation for XAV939 (XAV-Np), a tankyrase inhibitor that promotes β-catenin degradation, we investigated the effect of β-catenin inhibition on melanoma cell viability, migration, and tumor progression using a mouse model of conjunctival melanoma. XAV-Nps were uniform and displayed near-spherical morphology with size stability for upto 5 days. We show that XAV-Np treatment of mouse melanoma cells significantly suppresses cell viability, tumor cell migration, and tumor spheroid formation compared to control nanoparticle (Con-Np) or free XAV939-treated groups. Further, we demonstrate that XAV-Np promotes immunogenic cell death (ICD) of tumor cells with a significant extracellular release or expression of ICD molecules, including high mobility group box 1 protein (HMGB1), calreticulin (CRT), and adenosine triphosphate (ATP). Finally, we show that local intra-tumoral delivery of XAV-Nps during conjunctival melanoma progression significantly suppresses tumor size and conjunctival melanoma progression compared to Con-Nps-treated animals. Collectively, our data suggest that selective inhibition of β-catenin in tumor cells using nanoparticle-based targeted delivery represents a novel approach to suppress tumor progression through increased tumor cell ICD.

Conjunctival Melanoma in Aotearoa-New Zealand: A 21-Year Analysis of Incidence and Survival

PURPOSE

Conjunctival melanoma (CM) is a rare and aggressive malignancy. Global studies demonstrate increased burden of disease in countries with high rates of cutaneous melanoma. There are currently no reports on CM incidence, trends, or survival within Aotearoa-New Zealand (NZ), a country with the highest global rates of cutaneous melanoma, which this study aims to address.

DESIGN

This was a retrospective review using the national cancer registry.

METHODS

Data on histologically confirmed CM diagnosed between January 1, 2000, and December 31, 2020, were obtained from the NZ Cancer Registry. Cases were identified using the International Classification of Disease, 10th edition (ICD-10) codes. Primary outcome measures were age-standardized incidence, trends, and survival.

RESULTS

A total of 68 CM cases were identified. There was a preponderance for females (n=40, 58.8%) and CM predominantly affected European patients (n=63, 92.6%). Median follow-up was 5.0 years [interquartile range (IQR)=2.4-9.9 y] and the median age at diagnosis was 68.5 years (IQR=57.0-79.0 y), with non-Europeans presenting at a significantly younger age [-17.3 y (95% CI: -31.3 to -3.2), P =0.019] than Europeans. The annual age-adjusted incidence(±SD) was 0.6±0.2 cases per million population per year with a stable incidence trend over 21 years. All-cause mortality was found in 28 cases (41.2%) and the median time to death was 3.76 years (IQR=2.1-5.7 y). Five-year all-cause survival and disease-specific survival was 69% and 90%, respectively.

CONCLUSIONS

This is the first report on CM incidence, trends, and mortality in NZ. The CM burden is in line with European and North American data, despite NZ having the highest rate of cutaneous melanoma. The incidence remained stable over 2 decades.

Need for a Dedicated Ophthalmic Malignancy Clinico-Biological Biobank: The Nice Ocular MAlignancy (NOMA) Biobank

Ophthalmic malignancies include various rare neoplasms involving the conjunctiva, the uvea, or the periocular area. These tumors are characterized by their scarcity as well as their histological, and sometimes genetic, diversity. Uveal melanoma (UM) is the most common primary intraocular malignancy. UM raises three main challenges highlighting the specificity of ophthalmic malignancies. First, UM is a very rare malignancy with an estimated incidence of 6 cases per million inhabitants. Second, tissue biopsy is not routinely recommended due to the risk of extraocular dissemination. Third, UM is an aggressive cancer because it is estimated that about 50% of patients will experience metastatic spread without any curative treatment available at this stage. These challenges better explain the two main objectives in the creation of a dedicated UM biobank. First, collecting UM samples is essential due to tissue scarcity. Second, large-scale translational research programs based on stored human samples will help to better determine UM pathogenesis with the aim of identifying new biomarkers, allowing for early diagnosis and new targeted treatment modalities. Other periocular malignancies, such as conjunctival melanomas or orbital malignancies, also raise specific concerns. In this context, the number of biobanks worldwide dedicated to ocular malignancies is very limited. The aims of this article were (i) to describe the specific challenges raised by a dedicated ocular malignancy biobank, (ii) to report our experience in setting up such a biobank, and (iii) to discuss future perspectives in this field.

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.

Advances in conjunctival melanoma: clinical features, diagnostic modalities, staging, genetic markers, and management

Conjunctival melanoma, a rare malignancy of the ocular surface, is increasing in incidence. When small, straightforward excision with "no touch" surgery and cryotherapy at an experienced centre can provide excellent outcomes. When advanced, management is more complex and highly individualized. The risk of metastatic disease from conjunctival melanoma is as high as 30% and depends on tumour origin, American Joint Committee on Cancer (AJCC) classification, biomarkers, and perhaps most important, management technique. Metastatic disease can result in melanoma-associated death. Therefore, early detection and prompt directed treatment at an experienced centre are important for protection from metastasis. In this review, we provide an update on conjunctival melanoma clinical features, diagnostic modalities, AJCC staging, genetic markers, and the most critical, controlled management with minimization of tumour seeding. We detail the new era of characterization of conjunctival melanoma with molecular biomarkers that predict melanoma prognosis. This could lead to precision medicine with targeted approaches to specific mutations that improve patient survival. As we work together, the field of conjunctival melanoma is moving forward.

Long Noncoding RNA SAMMSON Promotes Melanoma Progression by Inhibiting FOXA2 Expression

Long noncoding RNAs (lncRNAs) play crucial roles in melanoma initiation and development, serving as potential therapeutic targets and prognostic markers for melanoma. lncRNA survival-associated mitochondrial melanoma-specific oncogenic noncoding RNA (SAMMSON) is upregulated in many types of human cancers. However, the functions of SAMMSON in melanoma have not been fully elucidated. This study is aimed at investigating the expression and functions of SAMMSON in melanoma development. Bioinformatics analysis was performed to determine the expression of SAMMSON and its correlation with the 10-year overall survival (OS) in melanoma patients. Cell proliferation, migration, invasion, and tumorigenesis were detected by MTT, colony formation, Transwell assays, and mouse xenograft model. The expression of cell cycle-related factors, epithelial-to-mesenchymal transition (EMT) makers, and matrix metalloproteinases (MMPs) was assessed by RT-qPCR and western blotting analysis. The results demonstrated that SAMMSON expression was upregulated in melanoma tissues and cells, and lower SAMMSON expression was correlated with longer 10-year OS. SAMMSON knockdown decreased the proliferation, migration, and invasion of melanoma cells by regulating the expression of proliferation-related genes, EMT factors, and MMPs, respectively. Additionally, Forkhead box protein A2 (FOXA2) was confirmed to be a target of SAMMSON, and the biological effects induced by FOXA2 overexpression were similar to those induced by SAMMSON silencing in melanoma cells. Further studies showed that SAMMSON downregulated FOXA2 expression in melanoma cells by modulating the EZH2/H3K27me3 axis. Taken together, our data indicate that SAMMSON plays an important role in melanoma progression and can be a valuable biomarker and therapeutic target in melanoma.

Bone metastasis in a case of primary acquired melanosis with atypia resulting from conjunctiva melanoma

A 66-year-old woman presented to a tertiary referral centre with a diagnosis of limbal stem cell deficiency secondary to multiple treatments for primary acquired melanosis (PAM) by her referring ophthalmologists. She was known with primary acquired melanosis with severe atypia of the right eye which had been treated with several excisions, cryotherapy and topical chemotherapy. She had PAM over 360° of alternating intensity. Throughout the follow-up period, she developed a cataract and subsequent a retinal detachment for which she underwent a phacovitrectomy on the right eye. There was no nodule present nor did the routine lymph nodes inspection show any enlargement. No abnormalities were observed on intranasal examination. Seven years after the last excision, a metastasis to the spine (Th3) was diagnosed. A complete systemic work-up and a pathological examination did not show any alternative primary melanoma in the body. The original histological material was reviewed again by an ophthalmopathologist. After a new round of stains and immunohistochemistry, the presence of atypical melanocytes in both the epithelium and stroma were found in a scar region leading to a renewed conclusion that the PAM in question was actually the primary melanoma.

Publication trends of research on conjunctival melanoma during 1997–2022: A 25-year bibliometric study

Background

Conjunctival melanoma (CM) is a life-threatening ocular tumor with a high rate of local recurrence and metastasis. Our objective is to analyze research trends in CM field and compare contributions from different countries, institutions and authors.

Methods

We extracted all CM-related publications published from 1997 to 2022 from the Web of Science database and applied Microsoft Excel and VOSviewer to review publication data, analyze publication trends, and visualize relevant data.

Results

A total of 708 publications were identified. The United States contributed the most publications (280) and citations (8,781 times) with the highest H-index value (47). The Ophthalmic Plastic and Reconstructive Surgery, British Journal of Ophthalmology, American Journal of Ophthalmology and Cornea were the most productive journal concerning CM, and Shields CL, Shields JA, Jager MJ as well as Finger PT had published the most papers in the field. Keywords were classified into three clusters: clinical research, management-related research and genetic research. The keywords “primary acquired melanosis”, “metastasis” and “BRAF mutations” were most frequently emerged. According to the average appearing year (AAY), targeted therapy (AAY of 2019.0) and nivolumab (AAY of 2018.7) were identified as the main focuses of the field in the near future.

Conclusion

In the past 25 years, the United States, Germany, England and the Netherlands held the leading position in the CM research. A group of scholars made important contributions to CM research and will continue to guide cutting-edge research. Treatments that have been shown to be effective for advanced cutaneous melanoma, such as targeted therapy and immunotherapy, are potential focuses for future CM research.

Clinicopathologic features and survival outcomes of ocular melanoma: a series of 31 cases from a tertiary university hospital

Background

We aimed to determine the effect of clinicopathologic features on overall survival among Caucasian ocular melanoma patients in the Central Anatolia region of Turkey.

Methods

This single-center study included conjunctival (n = 12) and uveal (n = 19) melanoma patients diagnosed between January 2008 and March 2020. Clinicopathologic features and outcomes were reviewed retrospectively. Five cases were tested for BRAF V600 mutations with real-time polymerase chain reaction, and one case was tested with next-generation sequencing. Survival was calculated using the Kaplan-Meier method.

Results

Thirty-one patients had a mean initial age of 58.32 years (median, 61 years; range 25 to 78 years). There were 13 male and 18 female patients. The median follow-up time was 43.5 months (range, 6 to 155 months) for conjunctival melanoma and 35 months (range, 8 to 151 months) for uveal melanoma. When this study ended, eight of the 12 conjunctival melanoma patients (66.7%) and nine of the 19 uveal melanoma patients (47.4%) had died. The presence of tumor-infiltrating lymphocytes was related to improved overall survival in conjunctival melanoma (p = .014), whereas the presence of ulceration (p = .030), lymphovascular invasion (p = .051), tumor in the left eye (p = .012), tumor thickness of > 2 mm (p = .012), and mitotic count of >1/mm² (p = .012) reduced the overall survival in conjunctival melanoma. Uveal melanoma tumors with the largest diameter of 9.1–15 mm led to the lowest overall survival among subgroups (p = .035). Involvement of the conjunctiva (p=.005) and lens (p = .003) diminished overall survival in uveal melanoma. BRAF V600 mutation was present in one case of conjunctival melanoma, GNAQ R183Q mutation was present in one case of uveal melanoma. Patients with uveal melanoma presented with an advanced pathological tumor stage compared to those with conjunctival melanoma (p = .019).

Conclusions

This study confirmed the presence of tumor-infiltrating lymphocytes as a favorable factor in conjunctival melanoma and conjunctival and lens involvement as unfavorable prognostic factors in uveal melanoma for overall survival, respectively.

Identification of New Vulnerabilities in Conjunctival Melanoma Using Image-Based High Content Drug Screening

Recent evidence suggests that numerous similarities exist between the genomic landscapes of both conjunctival and cutaneous melanoma. Since alterations of several components of the MAP kinases, PI3K/mTOR, and cell cycle pathways have been reported in conjunctival melanoma, we decided to assess the sensitivity of conjunctival melanoma to targeted inhibition mostly of kinase inhibitors. A high content drug screening assay based on automated fluorescence microscopy was performed in three conjunctival melanoma cell lines with different genomic backgrounds with 489 kinase inhibitors and 53 other inhibitors. IC50 and apoptosis induction were respectively assessed for 53 and 48 compounds. The genomic background influenced the response to MAK and PI3K/mTOR inhibition, more specifically cell lines with BRAF V600E mutations were more sensitive to BRAF/MEK inhibition, while CRMM2 bearing the NRASQ61L mutation was more sensitive to PI3k/mTOR inhibition. All cell lines demonstrated sensitivity to cell cycle inhibition, being more pronounced in CRMM2, especially with polo-like inhibitors. Our data also revealed new vulnerabilities to Hsp90 and Src inhibition. This study demonstrates that the genomic background partially influences the response to targeted therapy and uncovers a large panel of potential vulnerabilities in conjunctival melanoma that may expand available options for the management of this tumor.

American Joint Committee on Cancer (AJCC) tumor staging system predicts the outcome and metastasis pattern in conjunctival melanoma

PURPOSE

To assess the predictive value of the tumor staging system in the eighth edition of the American Joint Committee on Cancer Cancer Staging Manual (AJCC 8th-Edition) and histologic features for outcomes and metastasis patterns in conjunctival melanoma (CM).

DESIGN

Retrospective, single-center cohort study.

PARTICIPANTS

Eighty-three patients with CM were treated at our center between 2000 and 2021.

METHODS

We reviewed clinical and histopathological parameters and used Kaplan-Meier survival curves and Cox proportional hazards regression models for risk factor analyses.

MAIN OUTCOME MEASURES

Time to nodal/distant metastasis, disease-specific survival, metastatic pattern, and metastatic site.

RESULTS

At presentation, five patients (6%) had cT1 disease, 34 (41%) had cT2 disease, and 44 (53%) had cT3 disease. Four (5%) patients had nodal metastasis (N1), and none had distant metastasis (M1). During follow-up, 12 (14%) developed nodal metastasis, 29 (35%) developed distant metastasis, and 26 (31%) died of disease. Brain, liver and lung were common distant metastasis sites. Higher cT category was associated with increased risks of distant metastasis (p<0.001) and disease-specific death (p=0.002). The separate analysis of primary and recurrent tumors at presentation showed that the patients with cT3 tumors took a much higher risk of distant metastasis than those with cT2 tumors. Greater tumor thickness, ulceration, and the presence of regression were correlated with distant metastasis. Previously unreported mutations were detected in the tumor suppressor genes: FAT4 and SYK. Among the 29 patients who developed distant metastasis, we analyzed two patterns of metastasis: 11 patients (38%) developed nodal metastasis prior to distant metastasis, and 18 patients (62%) developed distant metastasis without previously known nodal metastasis. The patients with cT3 tumors were more likely to follow the latter metastasis pattern (p=0.02).

CONCLUSION

CM presented with mostly advanced stages and high rates of distant metastasis in the current Chinese cohort. This study confirmed the prognostic value of the tumor staging system in the AJCC 8th-Edition in Chinese patients. Histologic features, such as tumor thickness and ulceration, should be emphasized when assessing prognosis and guiding the treatment of CM.

New Therapeutic Approaches for Conjunctival Melanoma-What We Know So Far and Where Therapy Is Potentially Heading: Focus on Lymphatic Vessels and Dendritic Cells

Conjunctival melanoma (CM) accounts for 5% of all ocular melanomas and arises from malignantly transformed melanocytes in the conjunctival epithelium. Current therapies using surgical excision in combination with chemo- or cryotherapy still have high rates for recurrences and metastatic disease. Lately, novel signal transduction-targeted and immune checkpoint inhibitors like cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) inhibitors, programmed cell death protein-1 (PD-1) receptor inhibitors, BRAF- or MEK-inhibitors for systemic treatment of melanoma have improved the outcome even for unresectable cutaneous melanoma, improving patient survival dramatically. The use of these therapies is now also recommended for CM; however, the immunological background of CM is barely known, underlining the need for research to better understand the immunological basics when treating CM patients with immunomodulatory therapies. Immune checkpoint inhibitors activate tumor defense by interrupting inhibitory interactions between tumor cells and T lymphocytes at the so-called checkpoints. The tumor cells exploit these inhibitory targets on T-cells that are usually used by dendritic cells (DCs). DCs are antigen-presenting cells at the forefront of immune response induction. They contribute to immune tolerance and immune defense but in the case of tumor development, immune tolerance is often prevalent. Enhancing the immune response via DCs, interfering with the lymphatic pathways during immune cell migration and tumor development and specifically targeting tumor cells is a major therapeutic opportunity for many tumor entities including CM. This review summarizes the current knowledge on the function of lymphatic vessels in tumor growth and immune cell transport and continues to compare DC subsets in CM with related melanomas, such as cutaneous melanoma and mucosal melanoma.

Regulation of epigenetic homeostasis in uveal melanoma and retinoblastoma

Uveal melanoma (UM) and retinoblastoma (RB), which cause blindness and even death, are the most frequently observed primary intraocular malignancies in adults and children, respectively. Epigenetic studies have shown that changes in the epigenome contribute to the rapid progression of both UM and RB following classic genetic changes. The loss of epigenetic homeostasis plays an important role in oncogenesis by disrupting the normal patterns of gene expression. The targetable nature of epigenetic modifications provides a unique opportunity to optimize treatment paradigms and establish new therapeutic options for both UM and RB with these aberrant epigenetic modifications. We aimed to review the research findings regarding relevant epigenetic changes in UM and RB. Herein, we 1) summarize the literature, with an emphasis on epigenetic alterations, including DNA methylation, histone modifications, RNA modifications, noncoding RNAs and an abnormal chromosomal architecture; 2) elaborate on the regulatory role of epigenetic modifications in biological processes during tumorigenesis; and 3) propose promising therapeutic candidates for epigenetic targets and update the list of epigenetic drugs for the treatment of UM and RB. In summary, we endeavour to depict the epigenetic landscape of primary intraocular malignancy tumorigenesis and provide potential epigenetic targets in the treatment of these tumours.

Small but Challenging Conjunctival Melanoma: New Insights, Paradigms and Future Perspectives

Although its incidence has increased over the last decades, conjunctival melanoma (CM) remains a rare but challenging periocular malignancy. While there is currently no recognized standard of care, "no-touch" surgical excision followed by adjuvant treatments is usually recommended. Despite its small size, managing CM is challenging for clinicians. The first challenge is the high risk of tumour local recurrence that occurs in about one third of the patients. The management of locally advanced CM (≥T2) or multiple recurrences may require mutilating surgeries such as orbital exenteration (OE). The second challenge is the metastatic spread of CM that occurs in about one quarter of patients, regardless of whether complete surgical excision is performed or not. This highlights the infiltrative and highly aggressive behaviour of CM. Recently, attention has been directed towards the use of eye-sparing strategies to avoid OE. Initially, wide conservative surgeries followed by customized brachytherapy or radiotherapy have appeared as viable strategies. Nowadays, new biological insights into CM have revealed similarities with cutaneous melanoma. These new findings have allowed clinicians to reconsider the management of locally advanced CM with "medical" eye-sparing treatment as well as the management of metastatic spread. The aim of this review was to summarize the current and future perspectives of treatment for CM based on recent biological findings.

Prognostic Roles of BRAF, KIT, NRAS, IGF2R and SF3B1 Mutations in Mucosal Melanomas

BACKGROUND

The prognostic value of commonly recurrent mutations remains unclear in mucosal melanomas.

METHODS

Clinicopathologic parameters of 214 cases of mucosal melanomas diagnosed in 1989-2020 in several clinical institutions were analyzed. NRAS, KIT, BRAF, IGF2R and SF3B1 mutational analyses by Sanger sequencing and next generation sequencing-based assay were performed in a subset of cases.

RESULTS

Of the triple (BRAF, NRAS, NF1)-negative cases, APC, KIT and KRAS are detected mainly in sinonasal, vulvovaginal and anorectal melanomas, respectively. NRAS, KIT, BRAF, IGF2R and SF3B1 mutations are detected in 19% (37/198), 22% (44/197), 12% (25/201), 16% (22/138) and 15% (20/133) of cases, respectively. In univariate analyses, advanced stage (p = 0.016), 65 years or older (p = 0.048) and presence of ulceration (p = 0.027) are significantly correlated with worse overall survival (OS), respectively. NRAS mutation significantly correlates with worse OS (p = 0.028) and worse melanoma-specific survival (MSS) (p = 0.03) for all cases of mucosal melanomas. In multivariate analyses, NRAS mutation remains as an independent predictor of worse OS (p = 0.036) and worse MSS (p = 0.024).

CONCLUSION

NRAS mutation is a predictor of worse survival, independent of stage in mucosal melanomas. The significance of frequently mutated IGF2R in mucosal melanomas remains unclear.