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.

The efficacy and safety of dalpiciclib, a cyclin-dependent kinase 4/6 inhibitor, in patients with advanced head and neck mucosal melanoma harboring CDK4 amplification.

BACKGROUND: Mucosal melanoma (MM) is a rare but devastating subtype of melanoma. Our previous studies have demonstrated robust anti-tumor effects of cyclin-dependent kinase 4/6 (CDK 4/6) inhibitors in head and neck MM (HNMM) patient-derived xenograft models with CDK4 amplification. Herein, we aimed to investigate the efficacy and safety of dalpiciclib (SHR6390), a CDK4/6 inhibitor, in HNMM patients harboring CDK4 amplification. METHODS: The anti-tumor efficacy of dalpiciclib was assessed by HNMM patient-derived xenograft (PDX) models and patient-derived tumor cells (PDC) in vivo and in vitro. Immunohistochemical analyses and western blot were then performed to assess the markers of cell proliferation and CDK4/6 signaling pathway. For the clinical trial, advanced recurrent and/or metastatic HNMM patients with CDK4 amplification were treated with dalpiciclib 125 mg once daily for 21 consecutive days in 28-day cycles. The primary endpoint was disease control rate (DCR). Secondary endpoints included safety, objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). RESULTS: Dalpiciclib profoundly suppressed growth of HNMM-PDX and PDC with CDK4 amplification, whereas it showed relatively weak suppression in those with CDK4 wild type compared with vehicle. And dalpiciclib resulted in a remarkable reduction in the expression levels of Ki-67 and phosphorylated Rb compared with control group. In the clinical trial, a total of 17 patients were enrolled, and 16 patients were evaluable. The ORR was 6.3%, and the DCR was 81.3%. The estimated median PFS was 9.9 months (95% CI, 4.8-NA), and the median OS was not reached. The rate of OS at 12 months and 24 months was 68.8% (95% CI, 0.494-0.957) and 51.6% (95% CI, 0.307-0.866), respectively. The most frequent adverse events were neutrophil count decrease, white blood cell count decrease, and fatigue. CONCLUSIONS: Dalpiciclib was well-tolerated and displayed a durable benefit for HNMM patients with CDK4 amplification in this study. Further studies on CDK4 inhibitors and its combination strategy for MM are worth further exploration. TRIAL REGISTRATION: ChiCTR2000031608.

Survival of patients with mucosal melanoma in Cali, Colombia: a retrospective cohort study.

BACKGROUND: Mucosa melanoma is a rare condition with aggressive behavior and a less favorable prognosis compared to cutaneous melanoma. The objective of this study was to estimate the overall survival and clinical outcomes of patients diagnosed with mucosal melanoma in a Colombian hospital. METHODS: A retrospective cohort study was conducted at Fundación Valle del Lili, a single center located in Cali, Colombia. Patients aged ≥ 18 years, both sexes, diagnosed with mucosal melanoma by histopathology study were included between 2010-2019. Patients who received extra-institutional treatment or whose vital status was unknown during follow-up were excluded. Demographic, clinical and laboratory data were obtained from medical records and laboratory and pathology databases. A descriptive analysis was performed. Survival analysis was conducted using the Kaplan-Meier method. RESULTS: A total of 23 patients were included. Median age was 63 years old (IQR: 57-68) and 52.2% were woman. Clinical stage was 34.8% early, 26.1% locally advanced and 39.1% metastatic. The main primary locations were nasopharynx (30.4%), genitals (26.1%), rectum (21.7%), oral cavity (13%) and paranasal sinuses (8.7%). The majority received surgery (30.4%) and immunotherapy (26.1%) as first line treatment. Overall survival at one year was 80.8%, at three years 44.3%, and at five years 36.9%. CONCLUSION: Mucosal melanoma is a rare, aggressive disease with adverse oncological outcomes due to late diagnosis and limited treatment options. This study provides real-world data in a single-center of Colombia.

Development and validation of a nomogram for predicting overall survival in patients with sinonasal mucosal melanoma.

BACKGROUND: Sinonasal mucosal melanoma (SNMM) is a relatively rare malignant tumour with a poor prognosis. This study was designed to identify prognostic factors and establish a nomogram model to predict the overall survival (OS) of patients with SNMM. METHODS: A total of 459 patients with SNMM were selected from the Surveillance, Epidemiology, and End Results (SEER) database as the training cohort. Univariate and multivariate Cox regression analyses were used to screen for independent factors associated with patient prognosis and develop the nomogram model. In addition, external validation was performed to evaluate the effectiveness of the nomogram with a cohort of 34 patients with SNMM from Peking Union Medical College Hospital. RESULTS: The median OS in the cohort from the SEER database was 28 months. The 1-year, 3-year and 5-year OS rates were 69.8%, 40.4%, and 30.0%, respectively. Multivariate Cox regression analysis indicated that age, T stage, N stage, surgery and radiotherapy were independent variables associated with OS. The areas under the receiver operating characteristic curves (AUCs) of the nomograms for predicting 1-, 3- and 5-year OS were 0.78, 0.71 and 0.71, respectively, in the training cohort. In the validation cohort, the area under the curve (AUC) of the nomogram for predicting 1-, 3- and 5-year OS were 0.90, 0.75 and 0.78, respectively. Patients were classified into low- and high-risk groups based on the total score of the nomogram. Patients in the low-risk group had a significantly better survival prognosis than patients in the high-risk group in both the training cohort (P < 0.0001) and the validation cohort (P = 0.0016). CONCLUSION: We established and validated a novel nomogram model to predict the OS of SNMM patients stratified by age, T stage, N stage, surgery and radiotherapy. This predictive tool is of potential importance in the realms of patient counselling and clinical decision-making.

Head and Neck Mucosal Melanoma: Where Are We Now?

PURPOSE OF REVIEW: To highlight recent and relevant treatment considerations while managing mucosal melanoma. RECENT FINDINGS: Evidence is building to support the use of targeted therapy and immunotherapy while managing mucosal melanoma. Surgical resection with postoperative radiotherapy plays a major role in managing resectable disease. Recent studies evaluate the addition of targeted, and immunotherapies with an attempt to determine the most efficacious sequence of treatment.

Electrochemotherapy as adjuvant treatment in a sinonasal mucosal melanoma in elderly patient: a case report.

BACKGROUND: Sinonasal Mucosal Melanoma (SNMM) is a rare but aggressive disease. Surgery with free margins, when feasible, is the treatment of choice. In the last three decades, electrochemotherapy (ECT) has emerged as a local ablative procedure, performed with the Cliniporator, for cutaneous and mucosal tumours of different histology. We present a case report of an ECT treatment performed by means of a new endoscopic electrode, on an elderly patient affected by primary SNMM. METHODS: An 88-year-old man with a diagnosis of SNMM (cT4aN0M0)-Stage IV, of the left nasal fossa presented at our institution. Symptoms were epistaxis and complete left nasal obstruction. He refused sinonasal extended surgery and radiotherapy. He underwent a tumor debulking followed by ECT exclusively for symptom control, with palliative intent. RESULTS: The patient underwent SNMM debulking under general anaesthesia, followed by ECT on tumour margins. After the procedure, he had been free from symptoms for 5 months, with a good quality of life. Local recurrence was controlled with a new local debulking and ECT procedure on margins. The patient remained symptom free for the next 4 months. Seventeen months after diagnosis, the patient is mild symptomatic for sinonasal disease. Therefore, he developed a systemic disease progression. CONCLUSIONS: In our experience, ECT can be used as an adjuvant tool for symptom and local control in SNMM when extended surgery is out of curative intent or unfeasible. As expected, ECT does not appear to have any effect on systemic disease progression.

Sinonasal mucosal melanoma in The Netherlands between 2001 and 2021: a clinical and epidemiological overview of 320 cases.

PURPOSE: Sinonasal mucosal melanoma (SNMM) is a rare malignancy, characterised by high (local) recurrence rates and poor survival. Comprehensive understanding of tumour etiology is currently lacking, which complicates adequate tumour treatment. Besides examining trends in incidence, this study aims to assess the association between clinical characteristics, treatment practices and patient outcomes, with the objective of establishing a baseline from which SNMM management can be enhanced. METHODS: All newly diagnosed SNMM cases in The Netherlands between 2001 and 2021 were included using data from The Netherlands Cancer Registry (NCR). RESULTS: A total of 320 patients were included. The annual incidence rate for the overall population was stable over the inclusion period with an annual percentage change (APC) of only - 0.01%. The 5-year overall survival (OS) and relative survival (RS) were 24.5 and 32.4%, respectively. Relative survival did not increase over time. The addition of adjuvant radiotherapy to surgery was not associated with a higher OS and RS compared to surgery alone. CONCLUSION: Sinonasal mucosal melanoma is a rare disease with stable incidence rates in the Netherlands between 2001 and 2021. There has been no improvement in survival over the course of the inclusion period. The study reaffirms that adjuvant radiotherapy does not seem to improve patient outcomes. Given the generally poor outcomes for SNMM patients, novel therapeutic options ought to be considered in order to improve care.

Clinical practice consensus for the diagnosis and management of melanoma in Taiwan.

Melanoma is rare in Taiwan. Asian melanoma is distinct from Western melanoma because acral and mucosal melanoma accounts for the majority of melanoma cases, leading to distinct tumor behaviors and genetic profiling. With consideration of the clinical guidelines in Western countries, Taiwanese experts developed a local clinical practice consensus guideline. This consensus includes diagnosis, staging, and surgical and systemic treatment, based only on clinical evidence, local epidemiology, and available resources evaluated by experts in Taiwan. This consensus emphasizes the importance of surgical management, particularly for sentinel lymph node biopsies. In addition, molecular testing for BRAF is mandatory for patients before systemic treatment. Furthermore, immunotherapy and targeted therapy are prioritized for systemic treatment. This consensus aimed to assist clinicians in Taiwan in diagnosing and treating patients according to available evidence.

PRAME Updated: Diagnostic, Prognostic, and Therapeutic Role in Skin Cancer.

Preferentially Expressed Antigen in Melanoma (PRAME), a member of the cancer/testis antigen family, is central to the field of skin cancer diagnostics and therapeutics. As a nuclear receptor and transcriptional regulator, PRAME plays a critical role in inhibiting retinoic acid signalling, which is essential for cell differentiation and proliferation. Its aberrant overexpression in various malignancies, particularly cutaneous melanoma, is associated with more aggressive tumour phenotypes, positioning PRAME as both a diagnostic and prognostic marker. In melanoma, PRAME is typically highly expressed, in contrast to its weak or absent expression in benign nevi, thereby improving the accuracy of differential diagnoses. The diagnostic value of PRAME extends to various lesions. It is significantly expressed in uveal melanoma, correlating to an increased risk of metastasis. In acral melanomas, especially those with histopathological ambiguity, PRAME helps to improve diagnostic accuracy. However, its expression in spitzoid and ungual melanocytic lesions is inconsistent and requires a comprehensive approach for an accurate assessment. In soft tissue sarcomas, PRAME may be particularly helpful in differentiating melanoma from clear cell sarcoma, an important distinction due to their similar histological appearance but different treatment approaches and prognosis, or in detecting dedifferentiated and undifferentiated melanomas. In non-melanoma skin cancers such as basal cell carcinoma, squamous cell carcinoma, and Merkel cell carcinoma, the variable expression of PRAME can lead to diagnostic complexity. Despite these challenges, the potential of PRAME as a therapeutic target in melanoma is significant. Emerging immunotherapies, including T-cell-based therapies and vaccines targeting PRAME, are being investigated to exploit its cancer-specific expression. Ongoing research into the molecular role and mechanism of action of PRAME in skin cancer continues to open new avenues in both diagnostics and therapeutics, with the potential to transform the management of melanoma and related skin cancers.

[About a case of primary laryngeal mucosal melanoma in a patient with medical history of oropharyngeal squamous carcinoma]. / À propos d'un cas de mélanome muqueux primitif laryngé chez un patient présentant un antécédent de carcinome épidermoïde de l'oropharynx.

INTRODUCTION: Primary laryngeal mucosal melanoma is a rare tumour with a poor prognosis. Its often difficult diagnosis should rule out laryngeal metastatic localization of cutaneous melanoma. CASE PRESENTATION: We report a case of primary laryngeal mucosal melanoma diagnosed in a 65-year-old man, treated 6 years previously with radio-chemotherapy and surgery for squamous cell carcinoma of the right lateral oropharyngeal region. The definitive diagnosis of primary laryngeal mucosal melanoma was made on the resection specimen, whereas the initial biopsy of the epilaryngeal mass discovered during the patient's surveillance had concluded that it was a laryngeal recurrence of the known squamous cell carcinoma. DISCUSSION: Through this case, we propose to remind the main characteristics and the diagnostic pitfalls of these tumours.

Combinations of EGFR and MET inhibitors reduce proliferation and invasiveness of mucosal melanoma cells.

Mucosal melanoma (MM) is a very rare and aggressive type of cancer for which immunotherapy or targeted therapy such as BRAF/MEK inhibitors, used in cutaneous melanoma, usually fail. Due to our earlier experience showing the high effectiveness of epidermal growth factor receptor (EGFR) and hepatocyte growth factor receptor (MET) inhibitors in reducing the activation of the MAPK and PI3K/AKT signalling pathways, we aim to test whether these drugs would also be effective for mucosal melanoma. Cells representing two commercially available mucosal melanoma cell lines (GAK and HMVII) and one cell line obtained from a patient's vaginal melanoma were treated with MET or EGFR inhibitors, or combinations of these agents. The dual-inhibitor treatment strategy resulted in a decrease of cell proliferation, migration and invasion. Moreover, combinations of inhibitors led to reduction of pEGFR/EGFR and pMET/MET ratio and downregulation of PI3K/AKT and MEK/ERK1/2-based signalling pathways. Our findings indicate a potential therapeutic strategy based on EGFR and MET inhibitors in mucosal melanoma, which should be further evaluated in vivo and in clinical experiments. They also suggest that targeting multiple receptor tyrosine kinases may block signalling crosstalk and possibly delay the appearance of resistance to kinase inhibitors in mucosal melanoma cells.

Oncoviruses and melanomas: A retrospective study and literature review.

The role of human oncoviruses in melanoma has been poorly investigated. The aim of this study was to investigate the association between oncoviruses and melanomas searching for human papillomavirus (HPV), Epstein Barr virus (EBV), and human herpesvirus 8DNA in melanoma specimens. Formalin-fixed and paraffin-embedded tissue specimens of cutaneous, mucosal, and ocular melanomas (OM) were selected from the Pathology Departments of the Galliera Hospital (Genoa) and the University Hospitals of Turin and Cagliari. Cutaneous and mucosal nevi have been collected as controls. The oncoviruses search has been performed with different polymerase chain reaction reagent kits. Fifty-four melanomas (25 mucosal, 12 ocular, and 17 cutaneous) and 26 nevi (15 cutaneous and 11 mucosal) specimens were selected. The detection rate for one of the investigated oncoviruses was 17% in mucosal, 20% in ocular, and 0% in cutaneous melanomas (CMs). Despite the differences between groups seeming remarkable, there was no statistical significance (p > 0.5). Our data do not support a primary role of oncoviruses in melanoma carcinogenesis; however, the finding of HPV and EBV DNA in a considerable fraction of mucosal and OMs suggests that these viruses may act as cofactors in the development of extra-CMs.

Primary mucosal melanomas of the head and neck are characterised by overexpression of the DNA mutating enzyme APOBEC3B.

AIMS: Primary head/neck mucosal melanomas (MMs) are rare and exhibit aggressive biologic behaviour and elevated mutational loads. The molecular mechanisms responsible for high genomic instability observed in head/neck MMs remain elusive. The DNA cytosine deaminase APOBEC3B (A3B) constitutes a major endogenous source of mutation in human cancer. A3B-related mutations are identified through C-to-T/-G base substitutions in 5'-TCA/T motifs. Herein, we present immunohistochemical and genomic data supportive of a role for A3B in head/neck MMs. METHODS AND RESULTS: A3B protein levels were assessed in oral (n = 13) and sinonasal (n = 13) melanomas, and oral melanocytic nevi (n = 13) by immunohistochemistry using a custom rabbit α-A3B mAb (5210-87-13). Heterogeneous, selective-to-diffuse, nuclear only, A3B immunopositivity was observed in 12 of 13 (92.3%) oral melanomas (H-score range = 9-72, median = 40) and 8 of 13 (62%) sinonasal melanomas (H-score range = 1-110, median = 24). Two cases negative for A3B showed prominent cytoplasmic staining consistent with A3G. A3B protein levels were significantly higher in oral and sinonasal MMs than intraoral melanocytic nevi (P < 0.0001 and P = 0.0022, respectively), which were A3B-negative (H-score range = 1-8, median = 4). A3B levels, however, did not differ significantly between oral and sinonasal tumours (P > 0.99). NGS performed in 10 sinonasal MMs revealed missense NRAS mutations in 50% of the studied cases and one each KIT and HRAS mutations. Publicly available whole-genome sequencing (WGS) data disclosed that the number of C-to-T mutations and APOBEC3 enrichment score were markedly elevated in head/neck MMs (n = 2). CONCLUSION: The above data strongly indicate a possible role for the mutagenic enzyme A3B in head/neck melanomagenesis, but not benign melanocytic neoplasms.

Clinical significance of genetic profiling based on different anatomic sites in patients with mucosal melanoma who received or did not receive immune checkpoint inhibitors.

BACKGROUND: To date, data on the efficacy of targeted therapies for mucosal melanoma (MM) are limited. In this study, we analyzed genetic alterations according to the primary site of origin, which could provide clues for targeted therapy for MM. METHODS: We conducted a retrospective cohort study of 112 patients with MM. Targeted sequencing was performed to analyze genetic aberrations. Kaplan-Meier analysis was conducted with the log-rank test to compare the significance among subgroups. RESULTS: In total, 112 patients with MM were included according to the anatomic sites: 38 (33.9%) in the head and neck, 22 (19.6%) in the genitourinary tract, 21 (18.8%) in the anorectum, 19 (17.0%) in the esophagus, 10 (8.9%) in the uvea, and 2 (1.8%) in the small bowel. The most significantly mutated genes included BRAF (17%), KIT (15%), RAS (15%), TP53 (13%), NF1 (12%), SF3B1 (11%), GNA11 (7%), GNAQ (5%), and FBXW7 (4%). A large number of chromosomal structural variants was found. The anatomic sites of esophagus and small bowel were independent risk factors for progression-free survival (PFS, hazard ratio [HR] 4.78, 95% confidence interval [CI] 2.42-9.45, P < 0.0001) and overall survival (OS, HR 5.26, 95% CI 2.51-11.03, P < 0.0001). Casitas B-lineage lymphoma (CBL) mutants showed significantly poorer PFS and OS. In contrast, MM patients who received immune checkpoint inhibitors (ICIs) had a significantly more favorable OS (HR 0.39, 95% CI 0.20-0.75, P = 0.008). CONCLUSIONS: Our findings reveal the genetic features of patients with MM, mainly across six anatomic sites, offering a potential avenue for targeted therapies.

Anorectal melanoma.

Anorectal melanoma is an aggressive mucosal melanoma subtype with a poor prognosis. Although recent advancements have been seen for cutaneous melanoma, the optimal treatment paradigm for management of anorectal melanoma is evolving. In this review, we highlight differences in the pathogenesis of mucosal versus cutaneous melanoma, new concepts of staging for mucosal melanoma, updates to surgical management of anorectal melanoma, and current data for adjuvant radiation and systemic therapy in this unique patient population.

Mucosal melanomas of different anatomic sites share a common global DNA methylation profile with cutaneous melanoma but show location-dependent patterns of genetic and epigenetic alterations.

Cutaneous, ocular, and mucosal melanomas are histologically indistinguishable tumors that are driven by a different spectrum of genetic alterations. With current methods, identification of the site of origin of a melanoma metastasis is challenging. DNA methylation profiling has shown promise for the identification of the site of tumor origin in various settings. Here we explore the DNA methylation landscape of melanomas from different sites and analyze if different melanoma origins can be distinguished by their epigenetic profile. We performed DNA methylation analysis, next generation DNA panel sequencing, and copy number analysis of 82 non-cutaneous and 25 cutaneous melanoma samples. We further analyzed eight normal melanocyte cell culture preparations. DNA methylation analysis separated uveal melanomas from melanomas of other primary sites. Mucosal, conjunctival, and cutaneous melanomas shared a common global DNA methylation profile. Still, we observed location-dependent DNA methylation differences in cancer-related genes, such as low frequencies of RARB (7/63) and CDKN2A promoter methylation (6/63) in mucosal melanomas, or a high frequency of APC promoter methylation in conjunctival melanomas (6/9). Furthermore, all investigated melanomas of the paranasal sinus showed loss of PTEN expression (9/9), mainly caused by promoter methylation. This was less frequently seen in melanomas of other sites (24/98). Copy number analysis revealed recurrent amplifications in mucosal melanomas, including chromosomes 4q, 5p, 11q and 12q. Most melanomas of the oral cavity showed gains of chromosome 5p with TERT amplification (8/10), while 11q amplifications were enriched in melanomas of the nasal cavity (7/16). In summary, mucosal, conjunctival, and cutaneous melanomas show a surprisingly similar global DNA methylation profile and identification of the site of origin by DNA methylation testing is likely not feasible. Still, our study demonstrates tumor location-dependent differences of promoter methylation frequencies in specific cancer-related genes together with tumor site-specific enrichment for specific chromosomal changes and genetic mutations. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

Melanoma in skin of color: Part II. Racial disparities, role of UV, and interventions for earlier detection.

Despite a higher incidence of melanoma among White individuals, melanoma-specific survival is worse among individuals with skin of color. Racial disparities in survival are multifactorial. Decreased skin cancer education focused on people with skin of color, lower rates of screening, increased socioeconomic barriers, higher proportions of more aggressive subtypes, and underrepresentation in research and professional education contribute to delays in diagnosis and treatment. Although high, intermittent UV exposure during childhood has been established as a significant modifiable risk factor for melanoma in individuals with lighter skin phototypes, there are limited data on UV exposure and melanoma risk in people with darker skin phototypes. The second article of this continuing medical education series will examine factors contributing to racial disparities in melanoma-specific survival, discuss the role of UV radiation, and address the need for further research and targeted educational interventions for melanoma in individuals with skin of color.

Melanoma in skin of color: Part I. Epidemiology and clinical presentation.

Although there is a higher incidence of melanoma among non-Hispanic White individuals, melanoma is diagnosed at more advanced stages and associated with worse survival rates among individuals with skin of color (SOC). The proportions of melanoma subtypes differ across racial groups, with acral lentiginous melanoma and mucosal melanoma representing higher proportions of melanoma diagnoses in individuals with SOC compared to White individuals. The recognition of distinct differences in anatomic locations and dermatoscopic patterns may facilitate the appropriate differentiation of physiologic from pathologic pigmentation. The first article of this continuing medical education series will focus on the epidemiology and clinical presentation of melanoma in individuals with SOC, with the aim of improving early diagnoses and clinical outcomes.

Mucosal Melanoma: Epidemiology, Clinical Features, and Treatment.

PURPOSE OF REVIEW: Summarize the writings published in the last years on the management and novel therapies of mucosal melanoma (MM). RECENT FINDINGS: New research has demonstrated a difference between MM and cutaneous melanoma (CM) in their genomic and molecular landscapes, explaining the response's heterogeneity. Immunotherapy and targeted therapy have limited benefit, but novel therapies are rapidly expanding. MM is aggressive cancer occurring in gastrointestinal, respiratory, or urogenital mucosa; whose incidence is greater in the Asian population. The etiology and pathogenesis remain unclear since UV exposure is not a proven risk factor as in cutaneous melanoma. In contrast to CM, lesions on the mucosal surface are less likely to be recognized early; therefore, the disease is diagnosed in an advanced stage. Clinical manifestations, such as bleeding or pain, can help to detect this tumor, although the prognosis remains unfavorable with an overall 5-year survival rate of less than 20%. The mutational landscape of MM includes mutations of BRAF and NRAS, as well as mutations in the c-KIT/CD117 gene (in 50% of patients), thus limiting therapeutic interventions to immunotherapy. However, clinical studies show less responsiveness to immunotherapy compared to CM, therefore novel therapeutic strategies targeting new molecules are needed to improve the survival of patients with MM.

Definitive treatment for head and neck mucosal melanoma.

Head and neck mucosal melanoma is a rare clinical subtype of melanoma or head and neck cancer. Mucosal melanoma is aetiologically and molecularly distinct from cutaneous melanoma. The therapeutic efficacy of immune checkpoint inhibitors for head and neck mucosal melanoma remains unclear. Surgery is considered as the mainstay of treatment for locally advanced head and neck mucosal melanoma, and adjuvant radiotherapy has a role in local disease control. New treatment modalities, such as targeted therapy and immunotherapy, have changed the treatment of cutaneous melanoma. However, patients with mucosal melanoma have been excluded from most Phase III clinical trials. Due to its rarity, outcome data for locally advanced head and neck mucosal melanoma are scarce and are mainly based on retrospective studies with limited case numbers. The objective of this review was to provide an update and overview of clinical trials, prospective observational studies and retrospective studies and discuss future directions for multimodal treatment of locally advanced head and neck mucosal melanoma.