Vulvar Melanoma: Molecular Characteristics, Diagnosis, Surgical Management, and Medical Treatment

PRAME Immunohistochemistry for Distinguishing Vulvar and Vaginal Melanoma From Benign Melanocytic Nevi

Vulvovaginal melanoma (VVM) is a rare but deadly disease, accounting for 5% of all vulvar malignancies, with a 5-yr survival rate of only 47% for all stages of the disease. VVM is a distinct subset of melanoma, with a unique genomic profile and underlying pathogenesis unassociated with sun exposure. Distinguishing these rare malignancies from very common pigmented lesions of the vulva and vagina is challenging as histologic features often overlap between entities. PReferentially expressed Antigen in MElanoma (PRAME) is a melanoma-associated protein, and immunohistochemistry (IHC) for PRAME distinguishes cutaneous, oral mucosal, and retinal melanoma from atypical nevi. Given the biological differences between VVM and cutaneous melanoma, the utility of PRAME IHC for the diagnosis of VVM is unknown. We accrued a cohort of 20 VVM and 21 benign vulvar melanocytic nevi. We found that nuclear PRAME IHC staining with 4+ intensity was present in 85% of the VVM and 0% of the nevi. With the assistance of PRAME IHC, we found evidence of close or positive margin involvement in 3 of 10 cases where margins were originally diagnosed as negative for melanoma in situ. Our study is the first to assess PRAME IHC in a cohort of VVM cases and provides confidence for using PRAME IHC to assist with diagnosis and margin assessment in this rare disease.

A BEST classification system of large to giant congenital melanocytic nevi based on expert consensus and distribution characteristics

BACKGROUND

Large to giant congenital melanocytic nevi (LGCMN) significantly decrease patients' quality of life, but the inaccuracy of current classification system makes their clinical management challenging.

OBJECTIVES

To improve and extend the existing LGCMN 6B/7B classification systems by developing a novel LGCMN classification system based on a new phenotypic approach to clinical tool development.

METHODS

Three hundred and sixty-one LGCMN cases were categorized into four subtypes based on anatomic site: bonce (25.48%), extremity (17.73%), shawl (19.67%) and trunks (37.12%) LGCMN. A 'BEST' classification system of LGCMN was established and validated by a support vector machine classifier combined with the 7B system.

RESULTS

The most common LGCMN distributions were on bonce and trunks (bathing trunk), whereas breast/belly and body LGCMN were exceptionally rare. Sexual dimorphism characterized distribution, with females showing a wider range of lesions in the genital area. Nearly half of the patients with bathing trunk LGCMN exhibited a butterfly-like distribution. Approximately half of the LGCMN with chest involvement did not have nipple-areola complex involvement. Abdomen, back and buttock involvement was associated with the presence of satellite nevi (r = 0.558), and back and buttock involvement was associated with the presence of nodules (r = 0.364).

CONCLUSIONS

The effective quantification of a standardized anatomical site provides data support for the accuracy of the 6B/7B classification systems. The simplified BEST classification system can help establish a LGCMN clinical database for exploration of LGCMN aetiology, disease management and prognosis prediction.

A Pigmented Lesion of the Vulva Revealing Aggressive Melanoma: A Case Report

Vulvar melanoma (VM) is a rare and aggressive malignancy presenting unique challenges in diagnosis and management. This report presents the case of a 61-year-old female patient and explores the clinical characteristics, diagnostic modalities, treatment strategies, and prognosis associated with VM. The patient presented with a painless mass on the labia majora, which turned out to be an undifferentiated malignant tumor process consistent with melanoma on examination. Immunohistochemical analysis confirmed the diagnosis and subsequent imaging revealed metastatic disease necessitating palliative chemotherapy following radiotherapy. VM is a rare and aggressive form of melanoma. While surgery is the standard of care for early stages, advanced stages require a combination of immunotherapy and targeted treatments. Clinical trials are vital to improve our understanding of this condition and the various aspects of its care. Collaboration among experts is essential to achieve progress in managing these patients.

Multi-omics and tumor immune microenvironment characterization of a prognostic model based on aging-related genes in melanoma

Melanoma is a common and fatal cutaneous malignancy with strong invasiveness and high mortality rate. Clinically, elderly melanoma patients tend to exhibit stronger invasion ability and poorer prognosis. Given the heterogeneity of tumors, we analyzed the prognosis and risk assessment of melanoma through aging-related genes rather than age stratification. FOXM1 and CCL4 were identified to be closely associated with melanoma prognosis. Single-cell transcriptome analysis showed that FOXM1 was significantly up-regulated in tumor cells, while CCL4 was markedly elevated in immune cells. A melanoma prognostic model was constructed based on the two independent prognostic factors. This model showed a high accuracy in predicting the mortality of melanoma patients over several years. The patients in low-risk group appeared to have more immune cell infiltration and better immune therapy efficacy. Cellular experiments showed that CCL4 could promote apoptosis of melanoma cells through immune cells, and apoptosis could regulate the expression of FOXM1. In addition, the results of the spatial transcriptome and immunohistochemistry suggested that CCL4 was highly expressed in macrophages and the expression of FOXM1 in melanoma cell was negatively correlated with immune cell infiltration, especially macrophages. Here, we established a novel prognostic model for melanoma, which showed promising predictive performance and may serve as a biomarker for the efficacy of immune checkpoint inhibition therapy in melanoma patients. In addition, we explored the function of two genes in the model in melanoma.

Margin status in vulvovaginal melanoma: Management and oncologic outcomes of 50 cases

Objectives

To determine the influence of margin status, including preinvasive disease at the margin, on local recurrence and overall survival (OS) in patients with vulvovaginal melanoma.

Methods

All patients with Stage 0-III vulvovaginal melanoma treated with primary surgical management between 1/2010-12/2019 were included. Margin status was categorized as negative, preinvasive disease (atypical junctional melanocytic hyperplasia and melanoma in situ), and invasive melanoma. Kaplan-Meier analyses were performed for local progression free survival (PFS) and OS. The impact of clinical and pathologic factors on local PFS and OS were assessed with Cox-regression analyses.

Results

Fifty patients with a median follow-up of 48 months (range 3-119) were included. The median age was 63 years (range 20-83). Twenty percent (N = 10) had Stage 0 disease, 18% (N = 9) had Stage I, 46% (N = 23) had Stage II, and 16% (N = 8) had Stage III. Forty-four percent (N = 22) of patients had negative surgical margins, 46% (N = 23) had preinvasive disease at the margins, and 10% (N = 5) had invasive melanoma at the margins. The 5-year local PFS was 63% (95% CI: 42-78%) and OS was 60% (95% CI: 42-74%). Age, Breslow depth, stage, margin status, and re-resection did not significantly impact local PFS. In patients with preinvasive disease at the margin, all who recurred locally had Stage I-II disease.

Conclusion

Preinvasive disease at the surgical margins may play an important role in local recurrence in patients with Stage I-II vulvovaginal melanoma. Patients with early (Stage 0) and advanced (Stage III) disease rarely recur locally and may not benefit from re-resection.

Trends in Incidence and Survival of 1496 Patients with Mucosal Melanoma in The Netherlands (1990-2019)

BACKGROUND

Mucosal melanoma (MM) is a rare tumour with a poor prognosis. Over the years, immune and targeted therapy have become available and have improved overall survival (OS) for patients with advanced cutaneous melanoma (CM). This study aimed to assess trends in the incidence and survival of MM in the Netherlands against the background of new effective treatments that became available for advanced melanoma.

METHODS

We obtained information on patients diagnosed with MM during 1990-2019 from the Netherlands Cancer Registry. The age-standardized incidence rate and estimated annual percentage change (EAPC) were calculated over the total study period. OS was calculated using the Kaplan-Meier method. Independent predictors for OS were assessed by applying multivariable Cox proportional hazards regression models.

RESULTS

In total, 1496 patients were diagnosed with MM during 1990-2019, mostly in the female genital tract (43%) and the head and neck region (34%). The majority presented with local or locally advanced disease (66%). The incidence remained stable over time (EAPC 3.0%, p = 0.4). The 5-year OS was 24% (95%CI: 21.6-26.0%) with a median OS of 1.7 years (95%CI: 1.6-1.8). Age ≥ 70 years at diagnosis, higher stage at diagnosis, and respiratory tract location were independent predictors for worse OS. Diagnosis in the period 2014-2019, MM located in the female genital tract, and treatment with immune or targeted therapy were independent predictors for better OS.

CONCLUSION

Since the introduction of immune and targeted therapies, OS has improved for patients with MM. However, the prognosis of MM patients is still lower compared to CM, and the median OS of patients treated with immune and targeted therapies remains fairly short. Further studies are needed to improve outcomes for patients with MM.

Cutaneous Melanoma versus Vulvovaginal Melanoma—Risk Factors, Pathogenesis and Comparison of Immunotherapy Efficacy

Simple Summary

Melanoma of the vulva and vagina is a relatively rare neoplasm, unlike melanoma of the skin. Its prognosis is poor, and its pathogenesis is not fully understood. Immunotherapy is one of the rapidly developing cancer treatment methods. In this article, we focus on the pathogenesis of lower genital tract melanomas and related risk factors and compare the effectiveness of two groups of drugs—anti-PD-L1 and anti-CTLA4 antibodies—in the treatment of this condition. This type of immunotherapy is a relatively common treatment method for cutaneous melanoma but not for the rare vulvovaginal melanoma. For vulvovaginal melanoma, the effects of these treatments appear to be limited; however, this requires further research.

Abstract

Cutaneous melanoma is a relatively common neoplasm, with fairly well understood pathogenesis, risk factors, prognosis and therapeutic protocols. The incidence of this disease is increasing every year. The situation is different for rare malignancies such as vulvar melanomas and for the even rarer vaginal melanomas. The risk factors for vulvovaginal tumors are not fully understood. The basis of treatment in both cases is surgical resection; however, other types of treatments such as immunotherapy are available. This paper focuses on comparing the pathogenesis and risk factors associated with these neoplasms as well as the efficacy of two groups of drugs—anti-PD-L1 and anti-CTLA4 inhibitors—against both cutaneous melanoma and melanoma of the lower genital tract (vulva and vagina). In the case of cutaneous melanoma, the situation looks more optimistic than for vulvovaginal melanoma, which has a much worse prognosis and, as it turns out, shows a poorer response to immune therapy.

Successful treatment of metastatic vulvar malignant melanoma with toripalimab: A rare case report and review of the literature

RATIONALE

Vulvar melanoma is a rare and aggressive tumor with a high risk of local recurrence and distant metastasis. The prognosis is poor with a 5-year overall survival rate of only 46.6%. Management of vulvar melanoma remains a clinical challenge. Recent evidences have shown that immune checkpoint inhibitors are effective in the treatment of vulvar melanoma.

PATIENT CONCERNS AND DIAGNOSES

A 63-year-old woman with vulvar malignant melanoma suffered inguinal lymph node metastasis after vulvectomy and chemotherapy. She underwent inguinal lymph node dissection and inguinal radiotherapy. The tumor progressed again and she received immunotherapy.

INTERVENTIONS

The tumor progressed again, and she was admitted to our hospital and received toripalimab combined with apatinib and abraxane.

OUTCOMES

After 6 cycles of immunotherapy, the efficacy achieved partial remission. And with toripalimab as maintenance therapy, the patient achieved durable antitumor efficacy and good safety.

LESSONS

In this rare case, the patient with metastatic vulvar malignant melanoma had durable antitumor efficacy and good safety when receiving toripalimab.

Long Noncoding RNA LINC02249 Is a Prognostic Biomarker and Correlates with Immunosuppressive Microenvironment in Skin Cutaneous Melanoma

Skin cutaneous melanoma (SKCM) is one of the most aggressive and life-threatening tumors. It has a high incidence rate, as well as significant metastasis and fatality rates. To successfully treat SKCM and to increase the overall survival rate, early identification and risk stratification are both absolutely necessary. Long noncoding RNAs (lncRNAs) play a significant regulatory role in a variety of cancers. However, the expression and function of many lncRNAs have not been investigated. We evaluated the expression profile of the long noncoding RNA LINC02249 (LINC02249) in pan-cancers by using data on gene expression obtained from TCGA and GTEx. The biological function of LINC02249 was determined by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). The prognostic value of LINC02249 expression in SKCM patients was statistically analyzed. Besides, the ssGSEA approach was utilized in order to investigate the degree to which LINC02249 expression is correlated with tumor immune infiltration. In this study, the expression of LINC02249 was found to be abnormally high in a variety of tumors, according to our findings. When compared with nontumor specimens, the level of expression of LINC02249 was shown to be significantly elevated in SKCM samples. GO and KEGG assays revealed LINC02249 may be involved in tumor progression. High expression of LINC02249 was associated with shorter overall survival and disease-specific survival of SKCM patients. More importantly, multivariate methods revealed that LINC02249 expression was an independent prognostic factor for SKCM cases. Using ssGSEA, we found that the expression of LINC02249 was negatively associated with different tumor-infiltrating immune cells, especially aDC, Treg, and macrophages. Overall, our findings suggested that LINC02249 can serve as a novel biomarker to predict the prognosis and immune infiltration in SKCM.

Progressing Vulvar Melanoma Caused by Instability in cKIT Juxtamembrane Domain: A Case Report and Review of Literature

In order to identify the molecular pathways governing melanoma and track its progression, the next-generation sequencing (NGS) approach and targeted sequencing of cancer genes were employed. The primary tumor, as well as metastatic tissue, of an 84-year-old patient diagnosed with vulvar melanoma (VM), were investigated. The primary tumor specimen showed multiple somatic mutations in TP53 gene, suggesting its major contribution to melanoma origin. The metastatic sample showed additional alterations, including other melanoma-related genes. Clinical relevancy is postulated to juxtamembrane region instability of KIT gene (c-KIT). We did not identify BRAF or NRAS alterations, which are typical for the most common melanoma pathway–MAPK cascade. However, it should be noted that this is the first report evidencing PDGFRA in melanoma, although its role in triggering VM needs to be further elucidated.