Systemic BRAF/MEK Inhibitors as a Potential Treatment Option in Metastatic Conjunctival Melanoma

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.

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).

Case report: Drug-induced vitiligo during treatment with BRAF/MEK inhibitors in a patient with metastatic conjunctival melanoma

INTRODUCTION

Autoimmune side effects can be detected during the use of BRAF/MEK inhibitor. Although its frequency, mechanism and importance are not known exactly, there are cases reported in the literature.

CASE REPORT

We report a case of drug-induced vitiligo in a patient with metastatic conjunctival malignant melanoma who was treated with BRAF/MEK inhibition therapy.

MANAGEMENT AND OUTCOME

In the case, vitiligo was controlled with topical treatments. Follow-up process of the patient has been continuing with no progression on month 12 of the current treatment.

DISCUSSION

Although ICI-related autoimmune side effects and vitiligo have been described more frequently, vitiligo may also occur secondary to BRAK/MEK inhibition. This case also points out that cutaneous toxicity is manageable with no delay in treatment thanks to collaboration of dermatologists and oncologists.

Use of interferon alpha 2b to manage conjunctival primary acquired melanosis and conjunctival melanoma

Primary acquired melanosis (PAM) is acquired conjunctival pigmentation that can give rise to conjunctival melanoma (CM), a malignant tumor of the bulbar and palpebral conjunctiva or the caruncle. Surgical excision is the treatment of choice for this neoplasm. Topical chemotherapy is also used for patients with PAM with atypia or CM, hand in patients with recurrent or extensive disease, this may be an important option. Of the several chemotherapeutic drugs used, topical interferon alpha 2b (IFN-α2b) has become popular because of its low toxicity. Clinical evidence from case reports and case series supports the efficacy of IFN-α2b as the preferred adjuvant treatment for PAM and CM. In addition, topical IFN-α2b has been successfully applied to melanocytic tumors refractory to other treatments, such as cryotherapy and topical mitomycin C. In patients with locally advanced CM, the combination of IFN-α2b and systemic immunotherapy may serve as an alternative to exenteration. Given the low frequency of CM, long-term multicenter studies are needed to demonstrate the efficacy of IFN-α2b for preventing local recurrence and distant metastasis.

Integrative Exome and Transcriptome Analysis of Conjunctival Melanoma and Its Potential Application for Personalized Therapy

Importance

Greater understanding of molecular features of conjunctival melanoma (CM) may improve its clinical management.

Objective

To evaluate molecular features of CM and application of this information into clinical care.

Design, Setting, and Participants

In a prospective case series of CM with integrative exome and transcriptome analysis, 8 patients at an academic ocular oncology setting were evaluated. The study was conducted from November 2015 to March 2018.

Interventions/Exposures

Integrative exome and transcriptome analysis of CMs and clinical management of a patient's care by using this information.

Main Outcomes and Measures

Molecular characterization of CM and its potential clinical application.

Results

In the 8 patients (4 men) included in analysis, 4 subgroups of CM were observed, including the BRAF V600E mutation in 1 tumor, NRAS Q61R mutation in 3 tumors, NF1 mutations (Q1188X, R440X, or M1215K+ S15fs) in 3 tumors, and triple-wild type (triple-WT) in 1 tumor. The triple-WT case had CCND1 amplification and mutation in the CIC gene (Q1508X). Five tumors, including the triple-WT, also harbored mutations in MAPK genes. In addition to the genes linked to mitogen-activated protein kinase and phosphoinositol 3-kinase pathways, those involved in cell cycle and/or survival, ubiquitin-mediated protein degradation, and chromatin remodeling/epigenetic regulation (ATRX being the most frequently mutated: noted in 5 tumors) may play an important role. Other frequently mutated genes included PREX2 (n = 3), APOB (n = 4), and RYR1/2 (n = 4), although their relevance remains to be determined. The mutation burden ranged from 1.1 to 15.6 mutations per megabase (Mut/Mb) and was 3.3 Mut/Mb or less in 3 tumors and more than 10 Mut/Mb in 2 tumors. A patient with a large tumor and BRAF V600E mutation was treated with combined systemic BRAF (dabrafenib) and MEK (trametinib) inhibitors. After 3 months of therapy, her CM responded substantially and the residual tumor was removed by local surgical excision.

Conclusions and Relevance

The NRAS Q61R and NF1 mutations were more common than the BRAF V600E mutation in this series. Although small tumors (where incisional biopsy is not indicated) are treated with surgical excision regardless of mutational profile, in large tumors carrying the BRAF V600E mutation, neoadjuvant therapy with combined systemic BRAF and MEK inhibitors followed by local excision may be used as an alternative to exenteration. Integrative omics analysis of CM may be informative and guide clinical management and treatment in selected cases.

Molecular Genetics of Conjunctival Melanoma and Prognostic Value of TERT Promoter Mutation Analysis

The aim of this study was exploration of the genetic background of conjunctival melanoma (CM) and correlation with recurrent and metastatic disease. Twenty-eight CM from the Rotterdam Ocular Melanoma Study group were collected and DNA was isolated from the formalin-fixed paraffin embedded tissue. Targeted next-generation sequencing was performed using a panel covering GNAQ, GNA11, EIF1AX, BAP1, BRAF, NRAS, c-KIT, PTEN, SF3B1, and TERT genes. Recurrences and metastasis were present in eight (29%) and nine (32%) CM cases, respectively. TERT promoter mutations were most common (54%), but BRAF (46%), NRAS (21%), BAP1 (18%), PTEN (14%), c-KIT (7%), and SF3B1 (4%) mutations were also observed. No mutations in GNAQ, GNA11, and EIF1AX were found. None of the mutations was significantly associated with recurrent disease. Presence of a TERT promoter mutation was associated with metastatic disease (p-value = 0.008). Based on our molecular findings, CM comprises a separate entity within melanoma, although there are overlapping molecular features with uveal melanoma, such as the presence of BAP1 and SF3B1 mutations. This warrants careful interpretation of molecular data, in the light of clinical findings. About three quarter of CM contain drug-targetable mutations, and TERT promoter mutations are correlated to metastatic disease in CM.

Ocular Oncology-Primary and Metastatic Malignancies

Several neoplastic processes can involve the eye, either primarily or secondary to a systemic malignancy. The most common primary tumors of the eye include conjunctival and uveal melanoma, retinoblastoma, conjunctival and intraocular lymphoma, and ocular surface squamous neoplasia. Metastatic spread from systemic malignancies, especially of the breast and lung, also can involve the eye. A combination of ophthalmologic examination, ancillary testing, and cytologic/histopathologic evaluation leads to accurate diagnosis. Management consists of surgery, radiotherapy, chemotherapy, and immunotherapy delivered in various forms.

Fangchinoline suppresses conjunctival melanoma by directly binding FUBP2 and inhibiting the homologous recombination pathway

Conjunctival melanoma (CM) is a rare and fatal ocular tumour with poor prognosis. There is an urgent need of effective therapeutic drugs against CM. Here, we reported the discovery of a novel potential therapeutic target for CM. Through phenotypic screening of our in-house library, fangchinoline was discovered to significantly inhibit the growth of CM cells including CM-AS16, CRMM1, CRMM2 and CM2005.1. Further mechanistic experiments indicated that fangchinoline suppressed the homologous recombination (HR)-directed DNA repair by binding with far upstream element binding protein 2 (FUBP2) and downregulating the expression of HR factors BRCA1 and RAD51. In vitro and in vivo antitumour experiments revealed that fangchinoline increased the efficacy of cisplatin by blocking HR factors and reduced the drug dose and toxicity. In conclusion, our work provides a promising therapeutic strategy for the treatment of CM that is worthy of extensive preclinical investigation.

Orbital exenteration: an updated review with perspectives

Orbital exenteration is a radical and disfiguring surgery mainly performed in specialized tertiary care centers. Orbital exenteration has long been considered the treatment of choice for managing periocular tumors invading the orbit or primary orbital malignancies. Over the past decades, attention has been directed toward reducing the perioperative morbidity by developing new surgical devices and new strategies and promoting cosmetic rehabilitation by providing adequate facial prostheses. Despite these advances, several studies have questioned the role of orbital exenteration in improving overall survival. The last decade has been marked by the emergence of a new paradigm: the "eye-sparing" strategies based on conservative surgery with or without adjuvant radiotherapy and/or targeted therapies and immunotherapies. We summarize the data on orbital exenteration, including epidemiology, etiologies, use of surgical ablative and reconstructive techniques, complications, outcomes, and the related controversies.

Genetics of Ocular Melanoma: Insights into Genetics, Inheritance and Testing

Ocular melanoma consists of posterior uveal melanoma, iris melanoma and conjunctival melanoma. These malignancies derive from melanocytes in the uveal tract or conjunctiva. The genetic profiles of these different entities differ from each other. In uveal melanoma, GNAQ and GNA11 gene mutations are frequently found and prognosis is based on mutation status of BAP1, SF3B1 and EIF1AX genes. Iris melanoma, also originating from the uvea, has similarities to the genetic makeups of both posterior uveal melanoma (UM) and conjunctival melanoma since mutations in GNAQ and GNA11 are less common and genes involved in conjunctival melanoma such as BRAF have been described. The genetic spectrum of conjunctival melanoma, however, includes frequent mutations in the BRAF, NRAS and TERT promoter genes, which are found in cutaneous melanoma as well. The BRAF status of the tumor is not correlated to prognosis, whereas the TERT promoter gene mutations are. Clinical presentation, histopathological characteristics and copy number alterations are associated with survival in ocular melanoma. Tissue material is needed to classify ocular melanoma in the different subgroups, which creates a need for the use of noninvasive techniques to prognosticate patients who underwent eye preserving treatment.

PD-L1 Expression in 65 Conjunctival Melanomas and Its Association with Clinical Outcome

Conjunctival melanoma (CM) iss a rare and aggressive tumour that is increasing in frequency. The prognostic value of PD-L1 expression, alone or in combination with CD8 and PD-1 expression and the BRAF and NRAS status, has not been determined in CM to date. We evaluated the expression of PD-L1, CD8, PD-1 in CM and investigated whether there was an association between the expression of these markers and the BRAF and NRAS molecular profile as well as some clinico-pathological criteria. A total of sixty-five CM were assessed for PD-L1, PD-1, and CD8 expression by immunohistochemistry (IHC) and for BRAF and NRAS genomic alterations using molecular biology techniques and anti-BRAF and anti-NRAS antibodies. PD-L1 expression in tumour cells (TC) was very low or absent but detected in tumour-infiltrating immune cells (IC). A correlation was observed between the expression of PD-L1, CD8, and PD-1 in IC. No correlation between PD-L1 expression (in tumour and/or immune cells) and BRAF or NRAS mutations was observed. PD-L1 expression in IC correlated with a higher pTNM stage and PD-L1 expression in TC with worse disease-specific survival. PD-L1 expression is a potential prognostic biomarker that correlates with poor prognosis in CM patients.

Interdisciplinary Surveillance of Ocular Melanomas: Experiences in a German Tertiary Centre

BACKGROUND

In contrast to cutaneous melanoma, there are no uniform guidelines regarding surveillance of ocular (uveal, conjunctival) melanomas. A consented standard operating procedure (SOP) by the "Netzwerk onkologische Spitzenzentren" Germany only exists for conjunctival melanoma but not for uveal melanoma. Surveillance is partially based on German S3-guidelines for cutaneous melanoma and is carried out by oncologic centres in a multidisciplinary approach. This study aims to evaluate patients' adherence to surveillance programs and whether surveillance recommendations (examinations, intervals) can be realised.

METHODS

Retrospective analysis of all ocular melanoma patients overseen at the University Hospital of Cologne between 2008 and 2019. The study evaluates rates of successful patient integration into a standardized surveillance program and patients' surveillance adherence, subject to age, gender, primary therapy and tumour entity, respectively.

RESULTS

99 patients were included (56 female, 43 male), 83 of which had uveal melanomas and 16 conjunctival melanomas. Mean follow-up was 59 months. 81% of patients were integrated into a surveillance program. Surveillance was performed according to published recommendations in 78%. 13% of patients dropped out of the surveillance program after a mean period of 38 months.

CONCLUSIONS

Our data show a growing number of patients in standardized surveillance. However, there are still gaps. There is a need for guidelines specifically designed for ocular melanomas, allowing centres to offer patients an individualized approach.

Prognostic value of TERT promoter mutations in conjunctival melanomas in addition to clinicopathological features

AIMS

To evaluate the prognostic value of clinical, histopathological and molecular features and to relate different treatment modalities to clinical outcome in conjunctival melanomas (CM).

METHODS

Retrospective review of clinical, histopathological and BRAF V600E and telomerase reverse transcriptase (TERT) promoter mutation status and treatment modalities, correlated to recurrence and metastasis in 79 patients with CM, diagnosed between 1987 and 2015 in three tertiary referral centres in the Netherlands and Belgium.

RESULTS

Out of 78 evaluable patients, recurrences occurred in 16 patients and metastasis in 12 patients (median follow-up time 35 months (0-260 months)). Tumour thickness >2 mm, pT status, the presence of epithelioid cells, ulceration and mitoses was significantly correlated with metastasis (p value 0.046, 0.01, 0.02, 0.001 and 0.003, respectively). Furthermore, CM frequently harbour BRAF V600E and TERT promoter mutations (29% and 43%, respectively). TERT promoter mutations were correlated to shorter metastasis-free survival (p value 0.002). No significant correlation was found for clinical parameters and metastatic disease. Palpebral, forniceal and caruncular melanomas were more prone to develop recurrences (p value: 0.03). Most CM were treated with excision with adjuvant therapy.

CONCLUSION

In line with the recommendations in the Eighth Edition of the American Joint Committee on Cancer Staging for CM, the pathology report should include information about pT status, tumour thickness, presence of epithelioid cells, ulceration and mitoses. Furthermore, information about the presence of a TERT promoter mutation and BRAF V600E mutation is of interest for therapeutic decision making. The presence of a TERT promoter mutation is correlated to metastatic disease.

Transcriptional characterization of conjunctival melanoma identifies the cellular tumor microenvironment and prognostic gene signatures

This study characterizes the transcriptome and the cellular tumor microenvironment (TME) of conjunctival melanoma (CM) and identifies prognostically relevant biomarkers. 12 formalin-fixed and paraffin-embedded CM were analyzed by MACE RNA sequencing, including six cases each with good or poor clinical outcome, the latter being defined by local recurrence and/or systemic metastases. Eight healthy conjunctival specimens served as controls. The TME of CM, as determined by bioinformatic cell type enrichment analysis, was characterized by the enrichment of melanocytes, pericytes and especially various immune cell types, such as plasmacytoid dendritic cells, natural killer T cells, B cells and mast cells. Differentially expressed genes between CM and control were mainly involved in inhibition of apoptosis, proteolysis and response to growth factors. POU3F3, BIRC5 and 7 were among the top expressed genes associated with inhibition of apoptosis. 20 genes, among them CENPK, INHA, USP33, CASP3, SNORA73B, AAR2, SNRNP48 and GPN1, were identified as prognostically relevant factors reaching high classification accuracy (area under the curve: 1.0). The present study provides new insights into the TME and the transcriptional profile of CM and additionally identifies new prognostic biomarkers. These results add new diagnostic tools and may lead to new options of targeted therapy for CM.

[Personalized medicine in the treatment of periocular tumors : Targeted treatment and use of immune checkpoint inhibitors]

The aim of this article is to provide an overview on the current state of personalized medicine in the systemic treatment of selected periocular tumors, such as basal cell carcinoma, Merkel cell carcinoma and conjunctival melanoma. This article therefore provides an extensive current literature review from PubMed including the current guidelines and standard operating procedures (SOP). As 90% of basal cell carcinomas have a pathologic activation of the sonic hedgehog pathway, vismodegib is a new treatment option for inoperable or metastatic basal cell carcinoma and for patients with Gorlin-Goltz syndrome. A novel approach of systemic medicine for the treatment of metastatic Merkel cell carcinoma is immunotherapy using the immune checkpoint inhibitor avelumab. Other personalized immunotherapies, such as the checkpoint inhibitors pembrolizumab and nivolumab, the tyrosine kinase inhibitor pazopanib and the role of the hedgehog pathway in Merkel cell carcinomas are the subject of current research and will certainly play an important role in future treatment. In the narrow sense personalized medicine has only come true for metastatic conjunctival melanomas: systemic treatment with BRAF, MEK and/or checkpoint inhibitors is initiated only when a BRAF mutation is detected in the tumor or metastatic tissue. Systemic immunotherapy with the checkpoint inhibitors pembrolizumab and nivolumab can also be used as a treatment option in metastatic conjunctival melanomas. In summary, personalized medicine is a subject of current research and provides many new targeted treatment options especially for periocular malignancies; however, it also involves many great challenges in the development and implementation of new techniques and therapies.

Management Issues in Conjunctival Tumours: Conjunctival Melanoma and Primary Acquired Melanosis

Conjunctival melanoma is a rare malignant condition of the ocular surface. It is potentially lethal, with regional lymph node spread often preceding distant solid-organ metastasis. Due to its rarity and the long latency between treatment and local recurrence or the development of metastases, it is difficult to study. The literature is composed entirely of case series of varying quality, and there is significant variability in the management of this condition. This commentary attempts to distil the evidence base to provide practical management tips for the clinician.

Conjunctival Melanoma: Genetic and Epigenetic Insights of a Distinct Type of Melanoma

Conjunctival melanoma (CjM) is a rare, primary cancer of the ocular region. Genetic and epigenetic characteristics of conjunctival melanoma have not been completely elucidated yet. Conjunctival melanoma presents similarities with cutaneous melanoma, with substantial differences in the biological behavior. We reviewed the genetic and epigenetic insights of CjM involved in invasion and metastatic spread. CjM is commonly characterized by mutations of v-raf murine sarcoma viral oncogene homolog B1 (BRAF), neurofibromin 1 (NF1) and telomerase reverse transcriptase (TERT), high expression of mammalian target of rapamycin (mTOR) and heat shock protein 90 (HSP90), frequent phosphatase and tensin homolog (PTEN) loss and upregulation of specific miRNAs. These features should identify CjM as a distinct subset of melanoma with its own profile, which is more similar to cutaneous melanoma than mucosal melanoma and remarkably different from uveal melanoma.

Two cases of BRAF-mutated, bulbar conjunctival melanoma, and review of the published literature

We describe two patients with BRAF-mutated melanoma of the epithelioid cell type arising from primary acquired melanosis with severe atypia of the right bulbar conjunctiva. Patient 1 was a 71-year-old Japanese man. After adjuvant cryotherapy and enucleation of the right eyeball, therapy with vemurafenib was administered for a distant metastasis to a lumbar vertebra, accompanied by erythema multiforme and two keratinous tumours. The patient died due to metastases to the liver and multiple vertebrae, despite therapy with nivolumab and combination therapy with dabrafenib plus trametinib. Patient 2 was a 72-year-old Japanese man. After adjuvant cryotherapy, periodic mitomycin C eye drops, and excision of the superficial portion of the right parotid gland and the dissection of cervical lymph nodes, he was treated with adjuvant combination therapy with dabrafenib plus trametinib. Dermatologists should be familiar with BRAF-mutated conjunctival melanoma, which is usually located on the bulbar conjunctiva and associated with more frequent distant metastasis.

Two Late Recurrences of Conjunctival Melanoma

Purpose

To report a patient who developed two late recurrences of conjunctival melanoma (CoM), of which one occurred after orbital exenteration.

Methods

We describe the case of a patient based on clinical and histopathological examination.

Results

A 52-year-old patient was treated with local excision and cryotherapy for a CoM with primary acquired melanosis (PAM) near the limbus of the right eye. Twenty-one years later, a recurrence developed in the superior fornix of the same eye in an area with widespread PAM; an orbital exenteration was performed. After another 4 years, a painful nodule developed subcutaneously at the inferior margin of the right orbital socket. Pathology showed a recurrence of CoM with a BRAF V600K mutation, similar to both of the previous lesions (of 25 and 4 years earlier). The nodule was excised without additional therapy. No recurrences or metastases have been observed in the next 2.5 years. The proposed mechanism for the recurrence after surgery could be via dormant tumor cells that have spread prior to the procedure or via residual intraepithelial malignant melanocytes.

Conclusion

Very late recurrences of CoM are rare but may occur. Our case illustrates the need for long-term awareness of doctors and patients, even after extensive surgical procedures such as orbital exenteration.

Dabrafenib and Trametinib for BRAF-Mutated Conjunctival Melanoma

Background

Conjunctival melanoma is a potentially lethal malignancy of the ocular surface. There have been no therapeutic advancements made in the past several decades despite increasing prevalence of the disease.

Methods

The authors report the case of a 52-year-old Caucasian male with unresectable, recurrent conjunctival melanoma with V600 BRAF mutation who was treated with systemic BRAF/MEK inhibition.

Results

There was complete regression of local disease within the first 9 months. The patient remains without local recurrence or systemic metastasis at 1 year.

Conclusion

This is the first reported case of conjunctival melanoma with complete response to BRAF/MEK inhibition. As long as targeted therapy remains an option, patients with conjunctival melanoma should undergo mutational profiling of their tumor.

Sentinel lymph node biopsy in the management of conjunctival melanoma: current insights

Purpose: To evaluate the role of sentinel lymph node biopsy (SLNB) in conjunctival melanoma (CM).

Methods: This article provides a review of the literature from PUBMED.

Results: Data on SLNB in the management of CM are scarce and only two relatively large cohorts have been reported. Although indication criteria for SLNB vary slightly, positive findings can be expected in 11%–13% of CM cases, including small tumors. False negative SLNB findings are rare (<10%). Failure to identify SLNB has been attributed to the surgical learning curve and recurrent tumors with scar tissue impeding spread of the tracer material. Reported 5-year survival rate following CM management including SLNB, is up to 79%, but there are no comparative cohort studies proving the assumed benefit. Adverse events reported were non-severe and transient.

Conclusion: Patients can potentially benefit from SLNB and the procedure can be offered to eligible patients. However, there is not enough evidence to support SLNB as a mandatory part of CM management.

The risk of dermatological toxicities of combined BRAF and MEK inhibition versus BRAF inhibition alone in melanoma patients: a systematic review and meta-analysis

BACKGROUND

This meta-analysis was conducted to assess the risk of dermatological toxicities of combined BRAF and MEK inhibition versus BRAF inhibition alone in melanoma patients.

METHODS

We considered relevant prospective randomized phase I, II, and III trials of melanoma patients on the combined BRAF and MEK inhibition versus BRAF inhibition, describing events of rash, photosensitivity reaction (PR), hyperkeratosis (HK), alopecia, cutaneous squamous-cell carcinom(cSCC), skin papilloma(SP), pruritus, and hand-foot syndrome(HFS), as eligible for inclusion.

RESULTS

Eight trials comprising 3163 patients were included in the meta-analysis. The relative risks(RRs) of developing all-grade rash with combined BRAF and MEK inhibition versus BRAF inhibition was 1.59 (95%CI, 1.35-1.86, p < 0.00001), HK 0.33(95%CI, 0.16-0.66, p = 0.002), SP 0.09(95%CI, 0.04-0.24, p < 0.00001), alopecia 0.30(95%CI, 0.19-0.48, p < 0.00001), cSCC 0.23(95%CI, 0.17-0.31, p < 0.00001), HFS 0.18(95%CI, 0.13-0.26, p < 0.00001) and PR 0.40(95%CI, 0.26-0.61, p < 0.0001), while the RRs of high-grade dermatological toxicities from all included trials were: rash 0.54(95%CI, 0.20-1.43, p = 0.21), HK 0.18(95%CI, 0.06-0.53, p = 0.002), SP 0.14(95%CI, 0.02-1.16, p = 0.07), alopecia 0.72(95%CI, 0.14-3.62, p = 0.69), cSCC 0.23(95%CI, 0.17-0.33, p < 0.00001), HFS 0.40(95%CI, 0.08-2.06, p = 0.27), and PR 0.14(95%CI, 0.04-0.51, p = 0.003), respectly.

CONCLUSION

Our analysis of data has demonstrated that combined BRAF and MEK inhibitor-based treatment is associated with an increased risk of all-grade rash and a decreased risk of all-grade and high-grade HK, SP, alopecia, cSCC, HFS, and PR compared with single BRAF inhibitor alone in melanoma patients. Appropriate prevention and management are recommended.

[Focus on clinical and pathological management of conjunctival melanocytic tumors]

Conjunctival-pigmented tumors are rare, but they are one of the most commonly encountered by the pathologist working with the department of ophthalmology. Nevus and melanoma can be encountered and have some histological difference compared to their cutaneous counterpart. Primary acquired melanosis (PAM) is a conjunctival specific entity. This clinical term includes several histological lesions ranging from benignity to melanoma precursor lesion. Histologic examination determines the therapy and the risk of progression to melanoma. We present here a histopathological, clinical and therapeutic synthesis of conjunctival-pigmented lesions, emphasizing the importance of a good understanding between clinicians and pathologists.

Characterization of a conjunctival melanoma cell line CM-AS16, newly-established from a metastatic Han Chinese patient

Conjunctival melanoma (CM) is associated with metastases formation, can be fatal, and occurs in all different races. While cell lines are essential for experimental research, all available CM cell lines are derived from Caucasian patients. Furthermore, they are not derived from metastases. We aimed to establish a new CM cell line from a parotid metastasis in a Han Chinese patient and to depict its characteristics. The novel cell line, CM-AS16, was obtained from a surgical parotid sample and determined as a unique one with short tandem repeat (STR) analysis. It has been successively sub-cultured in vitro for more than 100 passages and exhibits rapid proliferation and migration. Chromosome analysis shows abundant chromosome aberrations, while whole exome sequencing (WES) reveals a typical NRAS mutation (Q61R). In vivo tumor growth was successfully established in a NOD/SCID mice model, and the immunophenotypes, such as HMB45, Melan A, S100, SOX10 and Ki67, manifested similar between the original tumor and the xenograft by immunohistochemistry. A MEK inhibitor binimetinib prominently suppressed in vitro cell growth by inhibiting ERK1/2 phosphorylation. In addition, monoclonal cells were used to demonstrate the drug sensitivity of different cells. In conclusion, the first cell line, CM-AS16, that is derived from a CM in a Han Chinese patient has highly malignant characteristics and a typical NRAS mutation. It may be used as a tool for further exploration of the molecular mechanisms of CM.