MAPK Pathway and TERT Promoter Gene Mutation Pattern and Its Prognostic Value in Melanoma Patients: A Retrospective Study of 2,793 Cases

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.

Mucosal Melanoma: Review from a Pathologist Point of View

Mucosal melanomas are rare malignant tumors arising from the epithelia lining the inner mucosal surfaces of the body. Unlike cutaneous melanoma, we have a limited understanding of mucosal melanomas is currently limited. Mucosal melanomas are characterized by genetic alterations quite distinct from cutaneous melanomas; however, their causative and promoting factors are unknown. These melanomas are characteristically diagnosed at a later stage due to their occult locations, leading to a worse prognosis. Dedicated staging systems for mucosal melanomas exist only for sinonasal and conjunctival melanomas. Therefore, risk stratification of patients with mucosal melanomas, particularly those arising from the anogenital area, is challenging. Recent studies have shown that minor modifications of the AJCC 8th Edition cutaneous melanoma staging system can group patients fairly robustly; however, the proposed T-categorization systems have yet to be validated in larger cohorts. We summarize the demographic, clinical, histopathologic, and molecular features of common subtypes of mucosal melanomas and highlight the outstanding needs in this field.

Comprehensive insights on genetic alterations and immunotherapy prognosis in Chinese melanoma patients

Immune checkpoint inhibitors (ICI) have emerged as a promising therapeutic option for melanoma, which demonstrating improved clinical outcomes in melanoma patients regardless of specific genetic mutations. However, the identification of reliable biomarkers for predicting immunotherapy response and prognosis remains a challenge. In this study, we performed genetic profiling of the melanoma patients with different subtypes and evaluated the efficacy of ICI treatment. A total of 221 melanoma patients were included in our cohort, consisting primarily of acral lentiginous melanoma (ALM), cutaneous malignant melanoma (CMM), and mucosal malignant melanoma (MMM). Genetic analysis revealed BRAF mutations was predominant in CMM and NRAS mutations was prevalent in ALM. Copy number variants (CNVs) and structural variants (SV) were also detected, with CCND1 and CDK4 being the most affected genes in CNV and BRAF, ALK and RAF1 being the druggable targets in SV. Furthermore, NRAS mutations were associated with a poor prognosis in ALM, while TERT mutations were linked to unfavorable outcomes in CMM after receiving PD-1 therapy. Additionally, ALK expression exhibited improved outcomes in both ALM and CMM subtypes. Our study provides a comprehensive genomic and pathological profiling of Chinese melanoma patients, shedding light on the molecular landscape of the disease. Furthermore, numbers of gene mutations and ALK expression were identified as prognostic indicators. These findings contribute to the understanding of melanoma genetics in the Chinese population and have implications for personalized treatment approaches.

Phase II clinical trial of neoadjuvant anti-PD-1 (toripalimab) combined with axitinib in resectable mucosal melanoma

BACKGROUND

The outcome of patients with resectable mucosal melanoma is poor. Toripalimab combined with axitinib has shown impressive results in metastatic mucosal melanoma with an objective response rate of 48.3% and a median progression-free survival of 7.5 months in a phase Ib trial. It was hypothesized that this combination administered in the neoadjuvant setting might induce a pathologic response in resectable mucosal melanoma, so we conducted this trial.

PATIENTS AND METHODS

This single-arm phase II trial enrolled patients with resectable mucosal melanoma. Patients received toripalimab 3 mg/kg once every 2 weeks (Q2W) plus axitinib 5 mg two times a day (b.i.d.) for 8 weeks as neoadjuvant therapy, then surgery and adjuvant toripalimab 3 mg/kg Q2W starting 2 ± 1weeks after surgery for 44 weeks. The primary endpoint was the pathologic response rate according to the International Neoadjuvant Melanoma Consortium recommendations.

RESULTS

Between August 2019 and October 2021, 29 patients were enrolled and received treatment, of whom 24 underwent resection. The median follow-up time was 34.2 months (95% confidence interval 20.4-48.0 months). The pathologic response rate was 33.3% (8/24; 4 pathological complete responses and 4 pathological partial responses). The median event-free survival for all patients was 11.1 months (95% confidence interval 5.3-16.9 months). The median overall survival was not reached. Neoadjuvant therapy was tolerable with 8 (27.5%) grade 3-4 treatment-related adverse events and no treatment-related deaths. Tissue samples of 17 patients at baseline and after surgery were collected (5 responders and 12 nonresponders). Multiplex immunohistochemistry demonstrated a significant increase in CD3+ (P = 0.0032) and CD3+CD8+ (P = 0.0038) tumor-infiltrating lymphocytes after neoadjuvant therapy, particularly in pathological responders.

CONCLUSIONS

Neoadjuvant toripalimab combined with axitinib in resectable mucosal melanoma demonstrated a promising pathologic response rate with significantly increased infiltrating CD3+ and CD3+CD8+ T cells after therapy.

Challenges and opportunities in rare cancer research in China

Cancer is one of the major public health challenges in China. Rare cancers collectively account for a considerable proportion of all malignancies. The lack of awareness of rare cancers among healthcare professionals and the general public, the typically complex and delayed diagnosis, and limited access to clinical trials are key challenges. Recent years have witnessed an increase in funding for research related to rare cancers in China. In this review, we provide a comprehensive overview of rare cancers and summarize the status of research on rare cancers in China and overseas, including the trends of funding and publications. We also highlight the challenges and perspectives regarding rare cancers in China.

Cutaneous melanocytic tumor with CRTC1::TRIM11 fusion: a case report

BACKGROUND

Cutaneous Melanocytic Tumor with CRTC1::TRIM11 Fusion (CMTCT) represents a novel and rare entity in the realm of dermatological oncology, characterized by distinct melanocytic differentiation. This particular tumor type has yet to be officially recognized by the World Health Organization (WHO). CMTCT is generally perceived as a tumor with a relatively indolent nature; however, it is not devoid of metastatic potential. Therefore, ensuring complete surgical excision of the tumor, coupled with rigorous long-term follow-up, is paramount for patient management. In this context, we report the case of an 18-year-old female patient who presented with a dull red nodule on her left leg. Initial surgical intervention led to a pathological diagnosis of CMTCT, but it was determined that the tumor had not been fully excised. Consequently, a second surgical procedure was undertaken to achieve complete removal of the tumor. During a follow-up period of six months post-surgery, the patient showed no signs of local recurrence or metastasis, indicating a successful outcome.

CASE PRESENTATION

An 18-year-old female patient noticed a dull red nodule on her left leg three years ago, which exhibited slow growth over time. She underwent a subcutaneous tumor resection. Histological examination under high-power magnification revealed that the neoplasm consisted of epithelioid cells arranged in nests, fascicles, bundles, or sheets. The tumor cells had round or ovoid nuclei with prominent nucleoli and visible mitotic figures. Notably, areas resembling nevus cell clusters were observed. Immunohistochemical analysis confirmed melanocytic differentiation. Next-generation sequencing (NGS) identified a CRTC1::TRIM11 fusion, and fluorescence in situ hybridization (FISH) for CRTC1 confirmed rearrangement. Consequently, a diagnosis of cutaneous melanocytic tumor with CRTC1::TRIM11 fusion was established.

CONCLUSIONS

CMTCT is a rare tumor characterized by melanocytic differentiation. In this case, the tumor predominantly comprised epithelioid cells with localized nevus cell clusters. The expression of melanocyte markers could easily lead to a misdiagnosis as cutaneous melanoma. However, several distinguishing features were noted: the tumor was not connected to the epidermis, exhibited low cellular heterogeneity and proliferation index, and showed minimal cellular atypia. Additionally, tests for EWSR1 rearrangement (FISH) and BRAF V600E mutation (PCR-ARMS) were negative.This case underscores the importance of a comprehensive diagnostic approach when clinical, microscopic, immunohistochemical, and molecular findings do not align. The presence of nevus cell clusters morphology in the tumor cells enhances our understanding of this disease's histological spectrum and aids in avoiding misdiagnosis or missed diagnosis.

Phase Ib study of anlotinib in combination with anti-PD-L1 antibody (TQB2450) in patients with advanced acral melanoma

BACKGROUND

Acral melanoma, the most common subtype of melanoma in Asians, is often diagnosed at an advanced stage and responds poorly to current programmed cell death protein 1 (PD-1) inhibitors.

OBJECTIVES

To evaluate the safety and efficacy of TQB2450 and anlotinib in patients with advanced acral melanoma in a phase Ib study (NCT03991975).

METHODS

Patients received TQB2450 (1200 mg every 3 weeks) and anlotinib (10 mg or 12 mg once daily, 2-week on/1-week off) in the dose-escalation and dose-expansion phases. The primary endpoints were dose-limiting toxicity (DLT), maximum tolerated dose (MTD) and objective response rate (ORR).

RESULTS

Nineteen patients were enrolled between June 2019 and June 2022. The majority of patients (16 of 19 patients) received anlotinib and TQB2450 as first-line treatment. No DLTs were observed, and MTD was not reached. Eighteen (94.7%) out of 19 patients experienced treatment-related adverse events (TRAEs), but most were grade 1 or 2. Grade 3 or greater TRAEs occurred in seven patients (36.8%). The ORR was 26.3% (two complete responses and three partial responses). The disease control rate was 73.7%. The median duration of response was 30.3 months [95% confidence interval (CI): 5.8-NA]. The median progression-free survival (PFS) was 5.5 months (95% CI: 2.8-NA), and median overall survival was 20.3 months (95% CI: 14.8-NA). Whole-exome sequencing suggested that acquired drug resistance might be attributed to activation of the MAPK signalling pathway and transformation to an immunosuppressive tumour environment.

CONCLUSIONS

TQB2450 combined with anlotinib showed favourable tolerance and promising anti-tumour activity with a prolonged PFS compared with anti-PD1 monotherapy in patients with advanced acral melanoma.

Treatment of acral and mucosal melanoma: Current and emerging targeted therapies

Targeted therapies revolutionized the management of patients with advanced and metastatic cutaneous melanoma. However, despite recent advances in the understanding of the molecular drivers of melanoma and its treatment with targeted therapies, patients with rare and aggressive melanoma subtypes, including acral melanoma (AM) and mucosal melanomas (MM), show limited long-term clinical benefit from current targeted therapies. While patients with AM or MM and BRAF or KIT mutations may benefit from targeted therapies, the frequency of these mutations is relatively low, and there are no genotype-specific treatments for most patients with AM or MM who lack common driver mutations. The poor prognosis of AM and MM can also be attributed to the lack of understanding of their unique molecular landscapes and clinical characteristics, due to being under-represented in preclinical and clinical studies. We review current knowledge of the molecular landscapes of AM and MM, focusing on actionable therapeutic targets and pathways for molecular targeted therapies, to guide the development of more effective targeted therapies for these cancers. Current and emerging strategies for the treatment of these melanoma subtypes using targeted therapies are also summarized.

Clinicopathologic Features and Prognosis of Melanoma in Northeast China: A Region-Based Cohort Study of 229 Consecutive Cases

Melanoma has been reported in many parts of East Asia. However, there are no reports on the epidemiology of melanoma in Northeast China. In this study, we collected demographic, clinicopathologic, and treatment data of patients with melanoma treated at the First Hospital of Jilin University (Changchun, China). A total of 229 consecutive nonselective cases were analyzed for the incidence and clinicopathologic characteristics of melanoma. The median overall survival was 53.5 months. The 1-year, 3-year, and 5-year survival rates were 86.3, 66.4, and 44.8%, respectively. The median disease-free survival was 33.1 months, and the 1-year, 3-year, and 5-year disease-free survival rates were 75.0, 48.5, and 35.8%, respectively. Multivariate analysis showed that disease stage, Eastern Cooperative Oncology Group score, and lactic dehydrogenase were independent prognostic factors of overall survival. Pathologic subtype and stage were independent prognostic factors of disease-free survival. Furthermore, vascular invasion was a prognostic factor for overall survival in acral melanoma and a prognostic factor for disease-free survival in cutaneous melanoma. Compared with the Caucasian population, the population of Northeast China showed significant differences in disease location, pathologic subtype, gene status, and survival prognosis. In summary, our study showed that vascular invasion might be a prognostic factor in patients with acral and cutaneous melanoma.

Dabrafenib plus trametinib versus anti-PD-1 monotherapy as adjuvant therapy in BRAF V600-mutant stage III melanoma after definitive surgery: a multicenter, retrospective cohort study

Background

Both dabrafenib/trametinib (D/T) and anti-PD-1 monotherapy (PD-1) are approved adjuvant therapies for patients with stage III BRAF V600-mutant melanoma. However, there is still a lack of head-to-head comparative data. We aimed to describe efficacy and toxicity outcomes for these two standard therapies across melanoma centers.

Methods

This multicenter, retrospective cohort study was conducted in 15 melanoma centers in Australia, China, Germany, Italy, Japan, UK, and US. We included adult patients with resected stage III BRAF V600-mutant melanoma who received either adjuvant D/T or PD-1 between Jul 2015 and Oct 2022. The primary endpoint was relapse-free survival (RFS). Secondary endpoints included overall survival (OS), recurrence pattern and toxicity.

Findings

We included 598 patients with stage III BRAF V600-mutant melanoma who received either adjuvant D/T (n = 393 [66%]) or PD-1 (n = 205 [34%]) post definitive surgery between Jul 2015 and Oct 2022. At a median follow-up of 33 months (IQR 21-43), the median RFS was 51.0 months (95% CI 41.0-not reached [NR]) in the D/T group, significantly longer than PD-1 (44.8 months [95% CI 28.5-NR]) (univariate: HR 0.66, 95% CI 0.50-0.87, P = 0.003; multivariate: HR 0.58, 95% CI 0.39-0.86, P = 0.007), with comparable OS with PD-1 (multivariate, HR 0.90, 95% CI 0.48-1.70, P = 0.75). Similar findings were observed using a restricted-mean-survival-time model. Among those who experienced recurrence, the proportion of distant metastases was higher in the D/T cohort. D/T had a higher incidence of treatment modification due to adverse events (AEs) than PD-1, but fewer persistent AEs.

Interpretation

In patients with stage III BRAF V600-mutant melanoma post definitive surgery, D/T yielded better RFS than PD-1, with higher transient but lower persistent toxicity, and comparable OS. D/T seems to provide a better outcome compared with PD-1, but a longer follow-up and ideally a large prospective trial are needed.

Funding

Dr. Xue Bai was supported by the Beijing Hospitals Authority Youth Programme (QMS20211101) for her efforts devoted to this study. Dr. Keith T. Flaherty was funded by Adelson Medical Research Foundation for the efforts devoted to this study.

A real-world study of adjuvant anti-PD -1 immunotherapy on stage III melanoma with BRAF, NRAS, and KIT mutations

BACKGROUND

Melanoma frequently harbors BRAF, NRAS, or KIT mutations which influence both tumor development and treatment strategies. For example, it is still controversial whether adjuvant anti-PD-1 monotherapy or BRAF/MEK inhibitors may better improve the survival for resected BRAF-mutant melanoma. Furthermore, outcomes for melanoma with NRAS and KIT mutation receiving adjuvant immunotherapy remain unclear.

METHODS

One hundred seventy-four stage III melanoma patients who underwent radical surgery in Fudan University Shanghai Cancer Center (FUSCC) during January 2017 to December 2021 were included in this real-world study. Patients were followed up until death or May 30th, 2022. Pearson's chi-squared test or Fisher's exact test was performed for univariable analysis of the different category groups. Log-rank analysis was used to identify the prognostic factors for disease-free survival (DFS).

RESULTS

There were 41 (23.6%) patients with BRAF mutation, 31 (17.8%) with NRAS mutation, 17 (9.8%) with KIT mutation, and 85 (48.9%) wild-type patients without either genomic alteration of those three genes. Most ( n  = 118, 67.8%) of them were acral melanoma, while 45 (25.9%) were cutaneous subtype, and 11 were (6.3%) primary unknown. Among them, 115 (66.1%) patients received pembrolizumab or toripalimab monotherapy as adjuvant therapy; 22 (12.6%) patients received high-dose interferon (IFN), and 37 (21.3%) patients were just for observation. There was no statistical difference in clinicopathologic factors between anti-PD-1 group and IFN/OBS group. Of all the enrolled patients, anti-PD-1 group had a better DFS than IFN/OBS group ( p  = 0.039). In anti-PD-1 group, patients with BRAF or NRAS mutations had poorer DFS than wild-type group. No survival difference was found among patients harboring different gene mutations in IFN/OBS group. In wild-type patients, anti-PD-1 group had a better DFS than IFN/OBS group ( p  = 0.003), while no survival benefits were found for patients with BRAF, NRAS, or KIT mutations.

CONCLUSION

Although anti-PD-1 adjuvant therapy provides a better DFS in the general population and in wild-type patients, patients with BRAF, KIT or, especially, NRAS mutation may not benefit further from immunotherapy than conventional IFN treatment or observation.

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.

Molecular testing in melanoma for the surgical pathologist

The diagnostic work-up of melanocytic tumours has undergone significant changes in the last years following the exponential growth of molecular assays. For the practising pathologist it is often difficult to sort through the multitude of different tests that are currently available for clinical use. The molecular tests used in melanocytic pathology can be broadly divided into four categories: (1) tests that predict response to systemic therapy in melanoma; (2) tests that predict prognosis in melanoma; (3) tests useful in determining the type or class of melanocytic tumour; and (4) tests useful in the differential diagnosis of naevus versus melanoma (primarily used as an aid in the diagnosis of histologically ambiguous melanocytic lesions). This review will present an updated synopsis of major molecular ancillary tests used in clinical practice.

Prognostic value of genetic aberrations and tumor immune microenvironment in primary acral melanoma

BACKGROUND

Acral melanoma (AM) is the most common subtype in Chinese melanoma patients with a very poor prognosis. However, our understanding of the disease pathogenesis and molecular landscape is limited by the few studies that have been conducted. Here, we profiled the clinical characteristics, mutational landscapes and tumor immune microenvironment of AM patients to gain insights into disease characteristics and potential treatment strategies.

METHODS

A total of 90 AM patients were enrolled and their tissue samples were subjected to next-generation sequencing and multiplexed immunohistochemistry tests. Kaplan-Meier curves and log-rank tests were used to analyze the prognostic potential of various genetic aberrations and immune cell compositions in AM.

RESULTS

The median disease-free survival was 21.3 months and estimated median overall survival (OS) was 60 months. More advanced stages, older ages and thickness of greater than 4 mm were associated with worse prognosis in AM patients (HR = 2.57, 95% CI 1.25-5.29, p = 0.01; HR = 2.77, 95% CI 1.22-6.28, p = 0.02; HR = 3.43, 95% CI 1.51-7.82, p < 0.01, respectively), while patients who received post-surgical treatments had better survival (HR = 0.36, 95% CI 0.17-0.76, p = 0.01). The most frequently altered genes included BRAF (14.5%), KIT (16.9%), NRAS (12%), NF1 (10.8%), APC (7.2%), and ARID2 (6%). Copy number variations (CNV) were commonly found in CCND1 (19.3%), CDK4 (19.3%), MDM2 (14.5%) and FGF19 (12%). CDK4 amplifications was independently associated with shorter OS in AM patients (HR = 3.61, 95% CI 1.38-9.46, p = 0.01). CD8 ⁺ T cells (p < 0.001) and M1 macrophages (p = 0.05) were more highly enriched in the invasive margin than in the tumor center. Patients with higher levels of M1 macrophage infiltration in the invasive margin derived markedly longer OS (HR = 0.43, 95% CI 0.20-0.95, p = 0.03). Interestingly, in CDK4-amplified patients, there tended to be a low level of M1 macrophage infiltration in the invasive margin (p = 0.06), which likely explains the poor prognosis in such patients.

CONCLUSIONS

Our study provided a comprehensive portrait of the clinicopathological features, genetic aberrations and tumor microenvironment profiles in AM patients and identified candidate prognostic factors, which may facilitate development of additional therapeutic options and better inform clinical management of AM patients. Based on these prognostic factors, further studies should focus on enhancing the infiltration of M1 macrophages, especially in CDK4-amplified AM patients.

Variations in genetics, biology, and phenotype of cutaneous disorders in skin of color - Part I: Genetic, biologic, and structural differences in skin of color

Skin of color (SOC) populations include those who identify as Black/African, Hispanic/Latinx, Asian/Pacific Islander, American Indian/Native Alaskan, Indigenous Australian, Middle Eastern, biracial/multiracial, or non-White; this list is far from exhaustive and may vary between and within cultures. Recent genetic and immunological studies have suggested that cutaneous inflammatory disorders (atopic dermatitis, psoriasis, and hidradenitis suppurativa) and malignancies (melanoma, basal cell carcinoma, and cutaneous T-cell lymphoma) may have variations in their immunophenotype among SOC. Additionally, there is growing recognition of the substantial role social determinants of health play in driving health inequalities in SOC communities. It is critically important to understand that social determinants of health often play a larger role than biologic or genetic factors attributed to "race" in health care outcomes. Herein, we describe the structural, genetic, and immunological variations and the potential implications of these variations in populations with SOC. This article underscores the importance of increasing the number of large, robust genetic studies of cutaneous disorders in SOC to create more targeted, effective therapies for this often underserved and understudied population. Part II of this CME will highlight the clinical differences in the phenotypic presentation of and the health disparities associated with the aforementioned cutaneous disorders in SOC.

Intratumoral CD73: An immune checkpoint shaping an inhibitory tumor microenvironment and implicating poor prognosis in Chinese melanoma cohorts

Background

As a novel immune checkpoint, CD73 has been reported to play prominent roles in several malignancies. However, the significance of CD73 in melanoma remains ambiguous. This study sought to reveal the impact of CD73 on the tumor microenvironment (TME) and patients’ prognosis, and to investigate whether CD73 could be a therapeutic target in Chinese melanomas, which were dominated by acral and mucosal subtypes.

Methods

Two independent Chinese cohorts of 194 patients with melanoma were enrolled. CD73 and PD-L1 expression as well as CD8+ and CD56+ cell infiltrations were evaluated by immunohistochemistry in 194 resected melanoma samples. Clinical outcomes of patients were assessed utilizing the Kaplan-Meier plotter and Cox proportional hazard analysis. RNA-seq data was obtained from TCGA database. Gene set functional annotations were performed based on GO, KEGG and GSEA analysis. CIBERSORT, ssGSEA and TIMER were used to explore the association between CD73 and immune infiltration. These findings were validated by establishing tumor xenograft model, and functions of tumor-infiltrating immune cells were examined by flow cytometry and immunofluorescence.

Results

High CD73 expression showed poorer clinical outcomes and was identified as an independent prognostic indicator for survival in two cohorts. Expression of CD73 was more prevalent than PD-L1 in Chinese melanoma cohorts (54.6% vs 23.2%). Co-expression of both immune checkpoints was infrequent (12.9%) in melanoma, and 54.4% of PD-L1 negative cases showed elevated expression of CD73. CD73high tumors showed a microenvironment with fewer CD8+ T cells and CD56+ NK cells infiltration, which displayed a dysfunctional phenotype. With the treatment of CD73 inhibitor APCP, the amount of CD8+ T cells and CD56+ NK cells infiltrated in tumors was elevated and the immunosuppressive effect of CD73 was eliminated.

Conclusions

High CD73 expression was associated with an inhibitory TME and adverse clinical outcomes of melanoma. In comparison to PD-L1, CD73 was more prevalent and possessed more definite prognostic significance. Therefore, it may serve as a prognostic indicator and immunotherapeutic target next to PD-L1 in melanoma for Chinese population.

Single-agent anti-PD-1 or combined with ipilimumab in patients with mucosal melanoma: an international, retrospective, cohort study

BACKGROUND

Mucosal melanoma (MM) is a rare melanoma subtype with distinct biology and poor prognosis. Data on the efficacy of immune checkpoint inhibitors (ICIs) is limited. We determined the efficacy of ICIs in MM, analysed by primary site and ethnicity/race.

PATIENTS AND METHODS

Retrospective cohort study from 25 cancer centres in Australia, Europe, USA and Asia. Patients with histologically confirmed MM were treated with anti-PD1+/-ipilimumab. Primary endpoints were response rate (RR), progression-free survival (PFS), overall survival (OS) by primary site (naso-oral, urogenital, anorectal, other), ethnicity/race (Caucasian, Asian, Other) and treatment. Univariate and multivariate Cox proportional hazard model analyses were conducted.

RESULTS

In total, 545 patients were included: 331 (63%) Caucasian, 176 (33%) Asian and 20 (4%) Other. Primary sites included 113 (21%) anorectal, 178 (32%) urogenital, 206 (38%) naso-oral and 45 (8%) other. 348 (64%) received anti-PD1 and 197 (36%) anti-PD1/ipilimumab. RR, PFS and OS did not differ by primary site, ethnicity/race or treatment. RR for naso-oral was numerically higher for anti-PD1/ipilimumab (40%, 95% CI 29-54%) compared with anti-PD1 (29%, 95% CI 21-37%). 35% of patients that initially responded progressed. Median duration of response (mDOR) was 26 months (95% CI 18-NR [Not Reached]). Factors associated with short PFS were ECOG PS ≥3 (p<0.01), LDH >ULN (p=0.01), lung metastases (p<0.01) and ≥1 previous treatments (p<0.01). Factors associated with short OS were ECOG PS ≥1 (p<0.01), LDH >ULN (p=0.03), lung metastases (p<0.01) and ≥1 previous treatments (p<0.01).

CONCLUSIONS

MM has poor prognosis. Treatment efficacy of anti-PD1+/-ipilimumab was similar and did not differ by ethnicity/race. Naso-oral primaries had numerically higher response to anti-PD1/ipilimumab, without difference in survival. The addition of ipilimumab did not show greater benefit over anti-PD1 for other primary sites. In responders, mDOR was short and acquired resistance was common. Other factors, including site and number of metastases were associated with survival.

FMRP ligand circZNF609 destabilizes RAC1 mRNA to reduce metastasis in acral melanoma and cutaneous melanoma

BACKGROUND

Melanoma is a type of malignant tumor with high aggressiveness and poor prognosis. At present, metastasis of melanoma is still an important cause of death in melanoma patients. However, the potential functions and molecular mechanisms of most circular RNAs (circRNAs) in melanoma metastasis remain unknown.

METHODS

circRNAs dysregulated in melanoma cell subgroups with different metastatic abilities according to a screening model based on repeated Transwell assays were identified with a circRNA array. The expression and prognostic significance of circZNF609 in skin cutaneous melanoma and acral melanoma cells and tissues were determined by qRT-PCR, nucleoplasmic separation assays and fluorescence in situ hybridization. In vitro wound healing, Transwell and 3D invasion assays were used to analyse melanoma cell metastasis ability. Tail vein injection and intrasplenic injection were used to study in vivo lung metastasis and liver metastasis, respectively. The mechanism of circZNF609 was further evaluated via RNA immunoprecipitation, RNA pull-down, silver staining, and immunofluorescence colocalization assays.

RESULTS

circZNF609 was stably expressed at low levels in melanoma tissues and cells and was negatively correlated with Breslow depth, clinical stage and prognosis of melanoma patients. circZNF609 inhibited metastasis of acral and cutaneous melanoma in vivo and in vitro. Mechanistically, circZNF609 promoted the binding of FMRP protein and RAC1 mRNA, thereby enhancing the inhibitory effect of FMRP protein on the stability of RAC1 mRNA and ultimately inhibiting melanoma metastasis.

CONCLUSIONS

Our findings revealed that circZNF609 plays a vital role in the metastasis of acral and cutaneous melanoma through the circRNF609-FMRP-RAC1 axis and indicated that circZNF609 regulates the stability of RAC1 mRNA by combining with FMRP, which might provide insight into melanoma pathogenesis and a new potential target for treatment of melanoma.

Evolving Treatment Approaches to Mucosal Melanoma

PURPOSE OF REVIEW

This review mainly focuses on the unique features and the development of available therapeutic options for mucosal melanoma in different treatment settings, i.e., neoadjuvant, adjuvant, and palliative.

RECENT FINDINGS

Mucosal melanoma is distinct from cutaneous melanoma in epidemiology, clinical features, and molecular landscape, characterized by more aggressive biological behavior, lower mutational burden, more chromosomal structure variants, unique driver mutation profile, and distinct tumor microenvironment. Systemic therapy is generally less effective to mucosal melanoma than its cutaneous counterpart. Therapeutic landscape for mucosal melanoma has evolved substantially in recent years: with new targeted therapy options as well as combination therapies built on the backbone of anti-PD-1/PD-L1 antibodies available (esp. anti-angiogenic agent and PD-1/PD-L1 combination), which, based on early phase trial data, seem to be promising. Mucosal melanoma is unique and distinct from cutaneous subtype. Unraveling the unique features of mucosal melanoma is a key to improve clinical outcomes.

Gene mutations and clinical prognosis of mucosal melanoma in different locations of head and neck

BACKGROUND

Mucosal melanoma is the second most common subtype of melanoma in China and head and neck region is one of the main sites of this disease.

AIMS/OBJECTIVES

Analyzed the phenotypes of C-Kit, NRAS, PDGFRA and BRAF genes in patients with in different locations to explore the characteristics of gene mutations.

MATERIAL AND METHODS

96 patients were included in this study. C-Kit (exons 9, 11, 13, 17 and 18), NRAS (exons 1 and 2), PDGFRA (exons 12, 14 and 18) and BRAF (exons 11 and 15) were analyzed by PCR amplification and Sanger sequencing.

RESULTS

14 (14.58%) patients had C-Kit mutation, 6 (6.25%) had BRAF mutation, 23 (23.96%) had PDGFRA mutation, and 12 (12.50%) had NRAS mutation. The NRAS mutation (p = 0.037, 95%CI: 1.050-4.572) was an independent factor affecting distant metastasis and was most commonly found in the nasal cavity/paranasal sinuses (p = .043) while the BRAF mutation was more common in locations other than the nasal cavity/paranasal sinus (p = .008) and was associated with local recurrence.

CONCLUSIONS AND SIGNIFICANCE

Gene phenotypes of mucosal melanoma in different locations has differences. Lesions in the nasal cavity and paranasal sinus should be assessed separately from other parts such as the nasopharynx.

Anti-PD-1 antibody monotherapy versus anti-PD-1 plus anti-CTLA-4 combination therapy as first-line immunotherapy in unresectable or metastatic mucosal melanoma: a retrospective, multicenter study of 329 Japanese cases (JMAC study)

Background

Anti-programmed cell death protein 1 (PD-1) antibody monotherapy (PD1) has led to favorable responses in advanced non-acral cutaneous melanoma among Caucasian populations; however, recent studies suggest that this therapy has limited efficacy in mucosal melanoma (MCM). Thus, advanced MCM patients are candidates for PD1 plus anti-cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) combination therapy (PD1 + CTLA4). Data on the efficacy of immunotherapy in MCM, however, are limited. We aimed to compare the efficacies of PD1 and PD1 + CTLA4 in Japanese advanced MCM patients.

Patients and methods

We retrospectively assessed advanced MCM patients treated with PD1 or PD1 + CTLA4 at 24 Japanese institutions. Patient baseline characteristics, clinical responses (RECIST), progression-free survival (PFS), and overall survival (OS) were estimated using Kaplan–Meier analysis, and toxicity was assessed to estimate the efficacy and safety of PD1 and PD1 + CTLA4.

Results

Altogether, 329 patients with advanced MCM were included in this study. PD1 and PD1 + CTLA4 were used in 263 and 66 patients, respectively. Baseline characteristics were similar between both treatment groups, except for age (median age 71 versus 65 years; P < 0.001). No significant differences were observed between the PD1 and PD1 + CTLA4 groups with respect to objective response rate (26% versus 29%; P = 0.26) or PFS and OS (median PFS 5.9 months versus 6.8 months; P = 0.55, median OS 20.4 months versus 20.1 months; P = 0.55). Cox multivariate survival analysis revealed that PD1 + CTLA4 did not prolong PFS and OS (PFS: hazard ratio 0.83, 95% confidence interval 0.58-1.19, P = 0.30; OS: HR 0.89, 95% confidence interval 0.57-1.38, P = 0.59). The rate of ≥grade 3 immune-related adverse events was higher in the PD1 + CTLA4 group than in the PD1 group (53% versus 17%; P < 0.001).

Conclusions

First-line PD1 + CTLA4 demonstrated comparable clinical efficacy to PD1 in Japanese MCM patients, but with a higher rate of immune-related adverse events.

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Anti-PD-1 plus anti-CTLA-4 antibody therapy (PD1 + CTLA4) is an option for patients with advanced mucosal melanoma (MCM).

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Data on the efficacy of PD1 + CTLA4 compared with PD-1 monotherapy (PD1) for MCM, however, are limited.

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We retrospectively analyzed data from 329 Japanese patients with advanced MCM treated with PD1 or PD1 + CTLA4.

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No significant differences in objective response rate, progression-free survival, or overall survival were observed.

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Immune-related adverse events resulting in treatment cessation were higher in the PD1 + CTLA4 group.

TERT Promoter Mutational Status in the Management of Cutaneous Melanoma: Comparison with Sentinel Lymph Node Biopsy

BACKGROUND

While BRAF mutations seem important for early melanomagenesis, mutations in the TERT promoter (TERTp) are related to metastasis. Yet, in conventional melanoma management, risk stratification does not depend on molecular biomarkers that can indicate the stage of progression, but rather on clinical, pathological, sentinel lymph node (SLN), and radiologic evaluation. The aim of this work was to evaluate the frequency and prognostic impact of TERTp mutations, comparing their predictive value to those of conventional procedures in melanoma management.

METHODS

Mutational analysis of a series of 91 cases was performed. The correlations between TERTp and BRAF mutational status and clinicopathological features were assessed.

RESULTS

The mutation rate was 33% for TERTp and 30% for BRAF. There was 68% concordance between primary and metastatic samples for TERTp mutations and 92% for BRAF mutations. TERTp mutations are significantly associated with the presence of BRAF mutations, features of worse prognosis, and a reduced disease-free survival. Also, TERTp mutational status was similar to SLN biopsy as a predictive factor of cutaneous melanoma recurrence and metastasis.

CONCLUSIONS

The predictive value of TERTp mutations may be similar to that of SLN biopsy and its integration in the management algorithm of melanoma patients should be considered.

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.

Clinical Application of TERT Promoter Mutations in Urothelial Carcinoma

Urothelial carcinoma (UC) is a common urological malignancy with a high rate of disease recurrence. Telomerase activity, a hallmark of cancer characterized by overcoming the replicative senescence, is upregulated in over 90% of patients with UC. Somatic mutations in the promoter region of telomerase reverse transcriptase (TERT) are frequently detected in UC, and drive telomerase activity. Recent studies have demonstrated a strong association between TERT promoter mutation and tumorigenesis of UC. Also, TERT promoter mutation has great potential for diagnosis, as well as prognosis in UC treatment, and this is also applicable for the liquid biopsy techniques. In this review, we discuss the progress in these areas and highlight the challenges, clinical potential, and future direction for developing UC treatment methods.

Association of NRAS Mutation With Clinical Outcomes of Anti-PD-1 Monotherapy in Advanced Melanoma: A Pooled Analysis of Four Asian Clinical Trials

Background

Anti-PD-1 monotherapy is the standard therapy for advanced melanoma patients, including those with NRAS mutations. The influence of NRAS mutation on immunotherapy, especially in noncutaneous melanoma, is largely uncharacterized.

Materials and Methods

We analyzed clinical data of four clinical trials for advanced melanoma patients treated with anti-PD-1 monotherapy between 2016 and 2019. The impact of NRAS mutation on efficacy and outcome of immunotherapy were analyzed in cutaneous and noncutaneous groups separately.

Results

A total of 206 patients were assessed, including 92 cutaneous melanoma patients with 12 NRAS mutations and 114 noncutaneous melanoma patients with 21 NRAS mutations. In cutaneous melanoma, the response rates of NRAS mutant patients were lower than patients without NRAS mutations (9.5% vs. 23.9%), the median progression-free survival (PFS) and median overall survival (OS) were shorter for patients with NRAS mutations, although without significant difference for OS (P=0.081). In noncutaneous melanoma, the response rates were 0 and 13.7% for NRAS mutant and wild-type patients, the median PFS were 3.6 months (95% CI: 0.9-6.3) and 4.3 months (95%CI: 2.9-5.7) (P=0.015), and the median OS were 10.8 months (95% CI: 1.5-20.1) and 15.3 months (95% CI: 13.2-17.4) (P=0.025), respectively. In multivariate analysis, NRAS mutation, along with ECOG performance score and LDH level, was negatively associated with both PFS (HR 1.912, P=0.044) and OS (HR 2.210, P=0.025) in noncutaneous melanoma.

Conclusion

In advanced Asian melanoma treated with anti-PD-1 monotherapy, NRAS mutant patients had lower response rates and poorer prognoses compared to wild-type patients, especially in noncutaneous subtypes.

Immunotherapy in Acral and Mucosal Melanoma: Current Status and Future Directions

Acral and mucosal melanomas are extremely rare in Caucasians; however, they are the predominant melanoma subtypes in Asians and other non-Caucasian populations. Acral and mucosal melanomas share many clinicopathological features, including aggressive phenotypes, similar genetic landscapes, and grim prognoses. In spite of advances in melanoma management, patients with acral and mucosal melanomas show limited benefit from current therapies. The rarity of these subtypes of melanoma is a significant factor contributing to the poor understanding of these pathological subtypes and the lack of effective interventions. Furthermore, the mechanisms contributing to disparities between different types of melanoma remain largely unclear. Herein, we comprehensively review current knowledge on the clinicopathological characteristics and mutational landscapes of acral and mucosal melanomas, as well as providing an overview of current therapies for patients with these aggressive melanoma subtypes, focusing on available immunotherapeutic interventions. We also discuss pathological differences between different melanoma subtypes and summarize current knowledge on melanoma disparities between Asians and Caucasians. Finally, we discuss emerging immunotherapeutic strategies for the treatment of acral and mucosal melanomas, focusing on combination therapies with immune checkpoint inhibitors. Unraveling the unique features of acral and mucosal melanomas is key for their early diagnosis and for the development of effective therapies.

Cutaneous Melanoma Classification: The Importance of High-Throughput Genomic Technologies

Cutaneous melanoma is an aggressive tumor responsible for 90% of mortality related to skin cancer. In the recent years, the discovery of driving mutations in melanoma has led to better treatment approaches. The last decade has seen a genomic revolution in the field of cancer. Such genomic revolution has led to the production of an unprecedented mole of data. High-throughput genomic technologies have facilitated the genomic, transcriptomic and epigenomic profiling of several cancers, including melanoma. Nevertheless, there are a number of newer genomic technologies that have not yet been employed in large studies. In this article we describe the current classification of cutaneous melanoma, we review the current knowledge of the main genetic alterations of cutaneous melanoma and their related impact on targeted therapies, and we describe the most recent high-throughput genomic technologies, highlighting their advantages and disadvantages. We hope that the current review will also help scientists to identify the most suitable technology to address melanoma-related relevant questions. The translation of this knowledge and all actual advancements into the clinical practice will be helpful in better defining the different molecular subsets of melanoma patients and provide new tools to address relevant questions on disease management. Genomic technologies might indeed allow to better predict the biological - and, subsequently, clinical - behavior for each subset of melanoma patients as well as to even identify all molecular changes in tumor cell populations during disease evolution toward a real achievement of a personalized medicine.

Survival Benefits of Anti-PD-1 Therapy in Combination With Radiotherapy in Chinese Melanoma Patients With Brain Metastasis

Limited data reported the synergistic anti-tumor effect of anti-PD-1 (programmed death 1) therapy and radiotherapy on melanoma BM (brain metastasis). And the efficacy in the Chinese population is unclear. This study aimed to evaluate the efficacy of anti-PD-1 therapy and radiotherapy in Chinese melanoma patients with BM. We retrospectively reviewed 96 consecutive melanoma patients with BM treated at Sun Yat-Sen University Cancer Center. Patient demographics, BM characteristics and treatment details were carefully collected. The intracranial PFS (progression free survival) and OS (overall survival) were estimated using the Kaplan-Meier method. Twenty-five patients were treated with anti-PD-1 therapy and radiotherapy. Eighteen (72.0%) patients had SBRT (stereotactic body radiation therapy) or SRS (stereotactic radiosurgery) for BM, 1 (4.0%) patient had WBRT (whole brain radiation therapy), 6 (24.0%) patients had SBRT/SRS and WBRT. The median treatment period of anti-PD-1 therapy was 10.77 months. Objective intracranial response was observed in 15 (60%) patients, and 5 (20%) patients achieved CR (complete response). After a median follow-up of 16 months, 11 (44%) patients experienced intracranial PD (progressive disease), and 15 (60%) patients died. The median intracranial PFS and OS were 10.73 months (range, 1.67–38.83 months) and 15.87 months (range, 2.47–41.50 months), respectively. The 1-year intracranial PFS and OS were 61.9% (95% CI, 44.1–86.9%) and 62.5% (95%CI, 45.8–85.2%), respectively. Patients with BM can benefit from a combination of anti-PD-1 therapy and radiotherapy. It merits further investigation in melanoma patients with BM.

Real-world analysis of clinicopathological characteristics, survival rates, and prognostic factors in patients with melanoma brain metastases in China

PURPOSE

We aimed to establish the clinicopathological characteristics and prognostic factors of patients with melanoma brain metastases (MBM) in the East Asian population.

METHODS

Overall survival (OS) and intracranial progression-free survival (PFS) were evaluated by Kaplan-Meier analysis. Cox regression analyses were used to determine prognostic factors associated with intracranial PFS and OS.

RESULTS

Between July 2007 and December 2019, 431 patients diagnosed with MBM were enrolled. Mucosal subtype (p = 0.013), LDH level (p = 0.014), the number of MBM ≥ 4 (p = 0.02), local treatment (p < 0.0001) and the use of PD-1 inhibitors (p < 0.0001) were independent prognostic factors for intracranial PFS. Mucosal subtype (p = 0.022), LDH level (p = 0.005), no extracranial metastasis (p = 0.01), concurrent liver metastasis (p = 0.004), local treatment (p = 0.001) and the use of PD-1 inhibitors (p < 0.0001) were independent prognostic factors for OS. Mucosal subtype brain metastases had a poor response to PD-1 inhibitors (p = 0.007), with a shorter intracranial PFS than other subtypes. In BRAF mutation patients with MBM, the first-line BRAF/MEK inhibitor therapy group had an advantage in OS compared to the first-line anti-PD-1 therapy group (p = 0.043).

CONCLUSION

Our findings depict clinical characteristics and prognostic factors of MBM in the East Asian population, suggesting the mucosal subtype as an adverse prognostic and predictive factor for patients with MBM. For BRAF mutation patients with MBM, first-line BRAF/MEK inhibitor therapy may bring a potential survival benefit compared to first-line anti-PD-1 therapy.

[The significance of C-KIT gene mutations in the diagnosis and prognosis of malignant tumors]

Mutations in the C-KIT gene encoding type III receptor tyrosine kinase that regulates cellular processes, such as differentiation, survival, proliferation, migration, and apoptosis, are found in some neoplasms: gastrointestinal stromal tumor, mastocytosis, melanoma, breast carcinomas, myeloid leukemias, and a number of others. Tumors that exhibit these mutations are sensitive to therapy with tyrosine kinase inhibitors, which makes it necessary to correctly identify the mutation status by C-KIT in order to apply a personalized approach to therapy. This literature review shows that the type and localization of the C-KIT gene mutation are of crucial prognostic value and significance in choosing drugs for antitumor therapy, but traditional diagnostic methods fail to determine accurate mutation characteristics. Routine sequencing techniques focus on identifying the gene mutations associated with specific cellular processes, such as DNA damage and repair. The emergence of next-generation sequencing techniques has solved this problem, making it possible to fully analyze the genome of a malignant neoplasm, with constant screening for new mutations that appear as the tumor develops, affect the prognosis of the disease, and change its sensitivity to the antitumor therapy.

The Association Between Breast Cancer and Blood-Based Methylation of S100P and HYAL2 in the Chinese Population

Previous work has shown that DNA methylation in peripheral blood may be associated with malignancy; however, these studies have mainly been conducted within Caucasian populations. Here, we investigated the association between blood-based methylation of S100 calcium-binding protein P gene (S100P) and hyaluronoglucosaminidase 2 gene (HYAL2) and breast cancer (BC) via mass spectrometry in two independent case-control studies of the Chinese population with a total of 351 BC cases and 427 cancer-free female controls. In Study I, in which subjects had an average of 45 years, hypomethylation of S100P showed a protective effect for women ≤45 years (six out of nine CpG sites, p < 0.05) but not for women >45 years. In contrast, hypomethylation of HAYL2 was not correlated with BC in women ≤45 years but was a risk factor for women >45 years (three out of four CpG sites, p < 0.05). We proposed an age-dependent correlation between BC and methylation of S100P and HYAL2 and performed further validation in Study II with older subjects (average age = 52.5 years), where hypomethylation of both S100P and HYAL2 was a risk factor for BC (p < 0.05 for 10 CpG sites) as reported in Caucasians who develop BC around 55 years old. Together with the observation that Chinese cancer-free females having variant basal methylation levels comparing to Caucasians, we assumed that blood-based methylation might be modified by ethnic background, hormone status, and lifestyle. Here, we highlighted that the epigenetic biomarkers warrant validations when its application in variant ethnic groups is considered.

Uncommon Subtypes of Malignant Melanomas: A Review Based on Clinical and Molecular Perspectives

Malignant melanoma represents the most aggressive type of skin cancer. Modern therapies, including targeted agents and immune checkpoint inhibitors, have changed the dismal prognosis that characterized this disease. However, most evidence was obtained by studying patients with frequent subtypes of cutaneous melanoma (CM). Consequently, there is an emerging need to understand the molecular basis and treatment approaches for unusual melanoma subtypes. Even a standardized definition of infrequent or rare melanoma is not clearly established. For that reason, we reviewed this challenging topic considering clinical and molecular perspectives, including uncommon CMs-not associated with classical V600E/K BRAF mutations-malignant mucosal and uveal melanomas, and some unusual independent entities, such as amelanotic, desmoplastic, or spitzoid melanomas. Finally, we collected information regarding melanomas from non-traditional primary sites, which emerge from locations as unique as meninges, dermis, lymph nodes, the esophagus, and breasts. The aim of this review is to summarize and highlight the main scientific evidence regarding rare melanomas, with a particular focus on treatment perspectives.

TERT Promoter Mutation as an Independent Prognostic Marker for Poor Prognosis MAPK Inhibitors-Treated Melanoma

Although the development of mitogen-activated protein kinase (MAPK) inhibitors has greatly improved the prognosis of BRAFV600 cutaneous melanomas, the identification of molecular indicators for mutated patients at risk of early progression remains a major issue. Using an amplicon-based next-generation-sequencing (NGS) assay that targets cancer-related genes, we investigated co-occurring alterations in 89 melanoma samples. We analyzed both their association with clinicopathological variables and clinical significance in terms of progression-free survival (PFS) and overall survival (OS) according to BRAF genotyping. Among co-occurring mutations, TERT promoter was the most frequently mutated gene. Although no significant difference in PFS was observed in the presence or absence of co-occurring alterations to BRAFV600, there was a trend of longer PFS for patients harboring TERT c.-124C>T mutation. Of most interest, this mutation is an independent marker of good prognosis in subgroups of patients with poor prognosis (presence of brain metastasis and elevated level of lactate dehydrogenase, LDH). Moreover, combination of elevated LDH level, presence of brain metastasis, and TERT c.-124C>T mutation was identified as the best fit model for predicting clinical outcome. Our work revealed the potential interest of c.-124C>T status determination in order to refine the prognosis of BRAFV600 melanoma under mitogen-activated protein kinase (MAPK) inhibitors.

TERT and TERT promoter in melanocytic neoplasms: Current concepts in pathogenesis, diagnosis, and prognosis

BACKGROUND AND OBJECTIVE

Located on chromosome locus 5p15.33, telomerase reverse transcriptase (TERT or hTERT) encodes the catalytic subunit of telomerase which permits lengthening and preservation of telomeres following mitosis. Mutations in TERT promoter (TERT-p) upregulate expression of TERT, allowing survival of malignant cells and tumor progression in wide variety of malignancies including melanoma. The objective of this review is to examine the roles of TERT and TERT-p in the pathogenesis, diagnosis, and prognostication of cutaneous melanoma.

METHODS

All studies of TERT or TERT-p in cutaneous melanocytic neoplasms with the following inclusion criteria were reviewed: publication date between 2010 and 2019, English language, and series of ≥3 cases were reviewed for evidence supporting the role of TERT in pathogenesis, diagnosis, and prognosis. Studies with <3 cases or focused primarily on mucosal or uveal melanocytic tumors were excluded.

RESULTS AND CONCLUSION

TERT-p mutations are frequent in chronic and non-chronic sun damage melanoma and correlate with adverse prognosis, inform pathogenesis, and may provide diagnostic support. While TERT-p mutations are uncommon in acral melanoma, TERT copy number gains and gene amplification predict reduced survival. Among atypical spitzoid neoplasms, TERT-p mutations identify biologically aggressive tumors and support the diagnosis of spitzoid melanoma. TERT-p methylation may have prognostic value in pediatric conventional melanoma and drive tumorigenesis in melanoma arising within congenital nevi. Finally, TERT-p mutations may aid in the differentiation of recurrent nevi from recurrent melanoma.

PD-1 Blockade in Chinese versus Western Patients with Melanoma

In this trial of programmed cell death-1 (PD-1) blockade with toripalimab in previously treated Chinese patients with melanoma, unique histologic and molecular features may explain why the objective response rate is lower than those defined in Western populations. This work suggests future avenues for investigating mechanisms of melanoma formation and resistance to PD-1 blockade.See related article by Tang et al., p. 4250.

The mutational landscape of mucosal melanoma

Mucosal melanoma is a rare and aggressive subtype of melanoma that has a less favorable prognosis due to the lack of understanding and identification of oncogenic drivers. Recently, whole genome and whole exome sequencing have unveiled the molecular landscape and potential oncogenic drivers of mucosal melanoma, which remains distinct from cutaneous melanoma. In this review, we provide an overview of the genomic landscape of mucosal melanoma, with a focus on molecular studies identifying potential oncogenic drivers allowing for a better mechanistic understanding of the biology of mucosal melanoma. We summarized the published genomics and clinical data supporting the observations that mucosal melanoma harbors distinct genetic alterations and oncogenic drivers from cutaneous melanoma, and thus should be treated accordingly. The common drivers (BRAF and NRAS) found in cutaneous melanoma have lower mutation rate in mucosal melanoma. In contrast, SF3B1 and KIT have higher mutation rate in mucosal melanoma as compared to cutaneous melanoma. From the meta-analysis, we also observed that the mutational profiles are slightly different between the "upper" and "lower" regions of mucosal melanoma, providing new insights and therapeutic options for the mucosal melanoma patients. Mutations identified in mucosal melanoma should be incorporated into routine clinical testing, as there are targeted therapies already developed for treating patients with these mutations in the precision medicine era.

A Functional Synonymous Variant in PDGFRA Is Associated with Better Survival in Acral Melanoma

Purpose: Polymorphisms of genes in the platelet-derived growth factor (PDGF) signaling pathway have been found to predict cutaneous melanoma (CM) survival, but their clinical effects in acral melanoma (AM) patients have not been explored. The aim of this study was to characterize the functional effect of the tag single-nucleotide polymorphism (SNP) rs2228230:C>T and assess its association with clinical outcomes in AM patients.

Methods: The effect of rs2228230:C>T on mRNA structures and codon usage values were evaluated using in silico analyses. PDGF receptor alpha (PDGFRA) expression vectors with the rs2228230:C or rs2228230:T allele were constructed to evaluate the expression and signaling activity of PDGFRA. The expression of PDGFRA in AM samples was measured using in situ RNAscope hybridization and immunohistochemical staining. The association of the rs2228230 genotype with survival was analyzed in two independent AM cohorts.

Results: In silico analyses indicated that the rs2228230:T allele increases the minimum free energy and reduces synonymous codon usage. The rs2228230:T allele decreased the expression of PDGFRA by reducing the stability of its mRNA and protein as well as the signaling activity of the MAPK and PI3K/AKT pathways. PDGFRA mRNA and protein expression was significantly reduced in AM tissues with the rs2228230:T allele. The progression-free survival and overall survival of AM patients with the rs2228230:T allele were significantly longer than those of patients with the CC genotype.

Conclusion: Our study indicated that rs2228230:T can reduce the expression of PDGFRA and downstream signaling activity and is associated with better survival in AM patients.

Characterizations of Gene Alterations in Melanoma Patients from Chinese Population

Melanoma is a human skin malignant tumor with high invasion and poor prognosis. The limited understanding of genomic alterations in melanomas in China impedes the diagnosis and therapeutic strategy selection. We conducted comprehensive genomic profiling of melanomas from 39 primary and metastatic formalin-fixed paraffin-embedded (FFPE) samples from 27 patients in China based on an NGS panel of 223 genes. No significant difference in gene alterations was found between primary and metastasis melanomas. The status of germline mutation, CNV, and somatic mutation in our cohort was quite different from that reported in Western populations. We further delineated the mutation patterns of 4 molecular subgroups (BRAF, RAS, NF1, and Triple-WT) of melanoma in our cohort. BRAF mutations were more frequently identified in melanomas without chromic sun-induced damage (non-CSD), while RAS mutations were more likely observed in acral melanomas. NF1 and Triple-WT subgroups were unbiased between melanomas arising in non-CSD and acral skin. BRAF, RAS, and NF1 mutations were significantly associated with lymph node metastasis or presence of ulceration, implying that these cancer driver genes were independent prognostic factors. In summary, our results suggest that mutational profiles of malignant melanomas in China are significantly different from Western countries, and both gene mutation and amplification play an important role in the development and progression of melanomas.

ctDNA detected by ddPCR reveals changes in tumour load in metastatic malignant melanoma treated with bevacizumab

Bevacizumab is included in an increasing number of clinical trials. To find biomarkers to predict and monitor treatment response, cancer and angiogenesis relevant mutations in tumour and circulating tumour DNA (ctDNA) were investigated in 26 metastatic melanoma patients treated with bevacizumab. Patients with >1% BRAF/NRAS ctDNA at treatment start had significantly decreased progression free survival (PFS) and overall survival (OS) (PFS: p = 0.019, median 54 vs 774 days, OS: p = 0.026, median 209 vs 1064 days). Patients with >1% BRAF/NRAS ctDNA during treatment showed similar results (PFS: p = 0.002, OS: p = 0.003). ≤1% BRAF/NRAS ctDNA and normal lactate dehydrogenase (LDH) levels both significantly predicted increased response to treatment, but BRAF/NRAS ctDNA was better at predicting response compared to LDH at treatment start (OR 16.94, p = 0.032 vs OR 4.57, p = 0.190), and at predicting PFS (HR 6.76, p = 0.002) and OS (HR 6.78, p = 0.002) during therapy. ctDNA BRAF p.V600D/E/K and NRAS p.G12V/p.Q61K/L/R were better biomarkers for response prediction than TERT promoter mutations (OR 1.50, p = 0.657). Next generation sequencing showed that all patients with ≥2 mutations in angiogenesis-relevant genes had progressive disease, but did not reveal other biomarkers identifying responders. To conclude, ctDNA and LDH are useful biomarkers for both monitoring and predicting response to bevacizumab.

Immunohistochemistry as a Genetic Surrogate in Dermatopathology: Pearls and Pitfalls

Immunohistochemistry (IHC) is routinely performed in most laboratories, and other than purchase of commercially available antibodies, requires no additional equipment or reagents. As such, IHC is an accessible and relatively inexpensive test and one that can be performed quite quickly. This is in sharp contrast to genomic or mutational testing methodologies that are routinely "send out" tests as they require specialized equipment and reagents as well as individuals with expertise in the performance of the tests and analysis of the results, resulting in a prolonged turn-round-time and enhanced associated costs. However, many open questions remain in a rapidly changing therapeutic and scientific landscape with most obvious one being what exactly is the utility of "good old fashioned" IHC in the age of targeted therapy? For molecular applications, is a negative immunohistochemical result enough as a stand-alone diagnostic or predictive product? Is a positive immunohistochemical result perhaps more suitable for a role in screening for molecular alterations rather than a definitive testing modality? This review is an attempt to answer those very questions. We elucidate the broad range of entities in which IHC is currently used as a molecular surrogate and underscore pearls and pitfalls associated with each. Special attention is given to entities for which targeted therapies are currently available and to entities in which molecular data is of clinical utility as a prognosticator.

Prevalence of NRAS Mutation, PD-L1 Expression and Amplification, and Overall Survival Analysis in 36 Primary Vaginal Melanomas

Background

Primary vaginal melanomas are uncommon and aggressive tumors with poor prognosis, and the development of new targeted therapies is essential. This study aimed to identify the molecular markers occurring in these patients and potentially improve treatment strategies.

Materials and Methods

The clinicopathological characteristics of 36 patients with primary vaginal melanomas were reviewed. Oncogenic mutations in BRAF, KIT, NRAS, GNAQ and GNA11 and the promoter region of telomerase reverse transcriptase (TERT) were investigated using the Sanger sequencing. The expression and copy number of programmed death‐ligand 1 (PD‐L1) were also assessed.

Results

Mutations in NRAS, KIT, and TERT promoter were identified in 13.9% (5/36), 2.9% (1/34), and 5.6% (2/36) of the primary vaginal melanomas, respectively. PD‐L1 expression and amplification were observed in 27.8% (10/36) and 5.6% (2/36) of cases, respectively. PD‐L1 positive expression and/or amplification was associated with older patients (p = .008). Patients who had NRAS mutations had a poorer overall survival compared with those with a wild‐type NRAS (33.5 vs. 14.0 months; hazard ratio [HR], 3.09; 95% CI, 1.08–8.83). Strikingly, two patients with/without PD‐L1 expression receiving immune checkpoint inhibitors had a satisfying outcome. Multivariate analysis demonstrated that >10 mitoses per mm² (HR, 2.96; 95% CI, 1.03–8.51) was an independent prognostic factor.

Conclusions

NRAS mutations and PD‐L1 expression were most prevalent in our cohort of primary vaginal melanomas and can be potentially considered as therapeutic targets.

Implications for Practice

This study used the Sanger sequencing, immunohistochemistry, and fluorescence in situ hybridization methods to detect common genetic mutations and PD‐L1 expression and copy number in 36 primary vaginal melanomas. NRAS mutations and PD‐L1 expression were the most prevalent, but KIT and TERT mutations occurred at a lower occurrence in this rare malignancy. Two patients receiving immune checkpoint inhibitors had a satisfying outcome, signifying that the PD‐L1 expression and amplification can be a possible predictive marker of clinical response. This study highlights the possible prospects of biomarkers that can be used for patient selection in clinical trials involving treatments with novel targeted therapies based on these molecular aberrations.

Little is known about the molecular characteristics of primary vaginal melanoma. This article reports on the molecular markers of this rare and aggressive disease, focusing on improvements in treatment strategies.

Identification of prognostic biomarkers for malignant melanoma using microarray datasets

Malignant melanoma is one of the most common types of cancer worldwide. Efforts have been made to elucidate the pathology of malignant melanoma. However, its molecular mechanisms remain unclear. Therefore, the microarray datasets GSE3189, GSE4570 and GSE4587 from the Gene Expression Omnibus database were used for the elucidation of candidate genes involved in the initiation and progression of melanoma. Assessment of the microarray datasets led to the identification of differentially expressed genes (DEGs), which were subsequently used for function enrichment analysis. These data were utilized in the construction of the protein-protein interaction network and module analysis was conducted using STRING and Cytoscape software. The results of these analyses led to the identification of a total of 182 DEGs, including 52 downregulated and 130 upregulated genes. The functions and pathways found to be enriched in the DEGs were GTPase activity, transcription from RNA polymerase II promoter, apoptotic processes, cell adhesion, membrane related pathways, calcium signaling cascade and the PI3K-Akt signaling pathway. The identified genes were demonstrated to belong to a set of 10 hub genes biologically involved in proliferation, apoptosis, cytokinesis, adhesion and migration. Survival analysis and Oncomine database analysis revealed that the calmodulin gene family, BAX and VEGFA genes, may be associated with the initiation, invasion or recurrence of melanoma. In conclusion, the DEGs and hub genes identified in the present study may be used to understand the molecular pathways involved in the initiation and progression of malignant melanoma. Furthermore, the present study may aid in the identification of possible targets for the diagnosis and treatment of melanoma.

Prognostic role of NRAS isoforms in Chinese melanoma patients

Neuroblastoma rat-sarcoma viral oncogene homolog (NRAS) isoforms are expressed in melanoma tumor tissues, which have been described in Caucasian melanoma. However, the status and the clinical significance of NRAS isoforms in the Asian population have not been investigated on a large scale. We examined the expression levels of NRAS isoforms of 140 melanoma samples using quantitative real-time PCR. Furthermore, the relationship of mRNA expression of NRAS isoforms to clinicopathological characteristics and survival of patients was analyzed. Statistical analysis showed that NRAS isoform 2 expression was correlated with melanoma subtypes (P=0.007), and NRAS isoform 4 expression was correlated with tumor thickness (P=0.031) and clinical stage (P=0.006). The median overall survival for patients with high expression of NRAS isoform 3 was significantly shorter than that for patients with low expression of NRAS isoform 3 (P=0.007). In addition, high expression of NRAS isoform 5 was associated with a worse prognosis (P=0.049 and 0.002 for overall survival and disease-free survival, respectively). Multivariate Cox regression analysis showed that high expression levels of NRAS isoform 3 and isoform 5 were independent poor prognostic factors for patients. Our results indicated that the mRNA expressions of NRAS isoform 3 and isoform 5 may be novel indicators of the prognosis of Chinese melanoma patients.

Prognostic significance of human telomerase reverse transcriptase promoter region mutations C228T and C250T for overall survival in spinal chordomas

BACKGROUND

Spinal chordomas, a subtype of primary spinal column malignancies (PSCM), are rare tumors with poor prognosis, and we have limited understanding of the molecular drivers of neoplasia.

METHODS

Study design was a retrospective review of prospectively collected data with cross-sectional survival. Archived paraffin embedded pathologic specimens were collected for 133 patients from 6 centers within Europe and North America between 1987 and 2012. Tumor DNA was extracted and the human telomerase reverse transcriptase (hTERT) promoter was sequenced. The hTERT mutational status was correlated with overall survival (OS) and time to first local recurrence.

RESULTS

Ninety-two chordomas, 26 chondrosarcomas, 7 osteosarcomas, 3 Ewing's sarcomas, and 5 other malignant spinal tumors were analyzed. Median OS following surgery was 5.8 years (95% CI: 4.6 to 6.9) and median time to first local recurrence was 3.9 years (95% CI: 2.5 to 6.7). Eight chordomas, 2 chondrosarcomas, 1 Ewing's sarcoma, and 1 other malignant spinal tumor harbored either a C228T or C250T mutation in the hTERT promoter. In the overall cohort, all patients with hTERT mutation were alive at 10 years postoperative with a median OS of 5.1 years (95% CI: 4.5 to 6.6) (P = 0.03). hTERT promoter mutation was observed in 8.7% of spinal chordomas, and 100% of chordoma patients harboring the mutation were alive at 10 years postoperative compared with 67% patients without the mutation (P = 0.05).

CONCLUSIONS

We report for the first time that hTERT promoter mutations C228T and C250T are present in approximately 8.7% of spinal chordomas. The presence of hTERT mutations conferred a survival benefit and could potentially be a valuable positive prognostic molecular marker in spinal chordomas.