Melanoma Group Research Articles

Clarifying new molecular subtyping and precise treatment of melanoma based on disulfidptosis-related lncRNA signature

Disulfidptosis, the newest form of programmed cell death, is closely associated with the immune microenvironment of cancer cells. Long non-coding RNA (lncRNA) has also been found to play a crucial role in melanoma. However, the role of disulfidptosis-related lncRNA in melanoma remains unclear. Through bioinformatic analysis of the transcriptional, clinical, and pathological data from the TCGA-SKCM (The Cancer Genome Atlas—Skin cutaneous melanoma) database, we established a 2-Disulfidptosis-related lncRNA (DRL) prognostic model and a novel molecular subtype for melanoma. The survival and ROC curves of the 2-DRL prognostic model demonstrated its strong efficacy in predicting the prognosis of melanoma. The high-risk group of melanoma exhibited a significant decrease in ESTIMATEScore, ImmuneScore, and StromalScore, indicative of pronounced immune suppression and exhaustion. Subgroup C2 of melanoma displayed an immune-activated state, while subgroups C1 and C3 showed immune suppression and exhaustion, potentially leading to poorer prognosis. Subgroup C1 demonstrated better sensitivity to Zoledronate, UMI-77, Nilotinib, and Cytarabine. Subgroup C2 exhibited greater sensitivity to Ribociclib, XAV939, Topotecan, and Ruxolitinib. Subgroup C3 showed higher sensitivity to VX-11e, Ulixertinib, Trametinib, and Afatinib. This study revealed the immune microenvironment status and targeted drug sensitivity in melanoma patients with different risk scores and molecular subtypes, offering valuable guidance for clinical treatment and identifying significant DRL targets for future in-depth research.

The utility of DNA methylation profiling in the diagnosis of un-, de- and trans-differentiated melanoma: a series of 11 cases.

Melanomas are recognised for their remarkable morphological plasticity. Some tumours may lose conventional features and/or acquire non-melanocytic characteristics, referred to as undifferentiated, dedifferentiated and transdifferentiated melanoma. Despite this phenotypical variability, melanomas typically maintain their cancer driver aberrations, affecting genes such as BRAF, NRAS and NF1. Currently, little is known about whether the DNA methylation profile follows the loss or change of differentiation or is retained despite extensive morphological transformation. In this study we analysed 11 melanoma cases, comprising six males and five females, with a median age of 67 years, including five undifferentiated, four trans-differentiated and two de-differentiated melanomas. Undifferentiated and trans-differentiated tumours either arose in a patient with known melanoma and/or presented in the groin/axilla with molecular alterations consistent with melanoma. Cases with heterologous differentiation resembled chondrosarcoma, osteosarcoma, angiosarcoma and rhabdomyosarcoma both morphologically and immunohistochemically, while undifferentiated tumours resembled undifferentiated pleomorphic sarcoma. Methylome profiling was performed, and unsupervised clustering analysis revealed nine cases (five undifferentiated, three trans-differentiated and one de-differentiated) to cluster closely together with conventional melanomas from a reference set. Two cases clustered separately with a distinct group of conventional melanomas exhibiting H3K27me3 loss. Despite loss of differentiation and phenotypical plasticity, methylation patterns seem to be retained in undifferentiated, de-differentiated and trans-differentiated melanomas and represent useful diagnostic tools to enhance diagnostic precision in these diagnostically challenging cases.

Changes in the incidence of melanoma in Australia, 2006-2021, by age group and ancestry: a modelling study.

To estimate the incidence of melanoma in Australia among people with ancestries associated with low, moderate, or high risk of melanoma, by sex and 5-year age group; to establish whether age-specific incidence rates by ancestry risk group have changed over time. Modelling study; United States (SEER database) melanoma incidence rates for representative ancestral populations and Australian census data (2006, 2011, 2016, 2021) used to estimate Australian melanoma incidence rates by ancestry-based risk. Australia, 2006-2021. Age-specific invasive melanoma incidence rates, and average annual percentage change (AAPC) in age-specific melanoma rates, by ancestry-based risk group, sex, and 5-year age group. The proportion of people in Australia who reported high risk (European) ancestry declined from 85.3% in 2006 to 71.1% in 2021. The estimated age-standardised melanoma incidence rate was higher for people with high risk ancestry (2021: males, 82.2 [95% confidence interval {CI}, 80.5-83.8] cases per 100 000 population; females, 58.5 [95% CI, 57.0-59.9] cases per 100 000 population) than for all Australians (males, 67.8 [95% CI, 66.5-69.2] cases per 100 000 population; females, 45.4 [95% CI, 44.3-46.5] cases per 100 000 population). AAPCs were consistently positive for Australians aged 50 years or older, both overall and for people with high risk ancestry, but were statistically significant only for some age groups beyond 65 years. AAPCs were negative for people aged 34 years or younger, but were generally not statistically significant. Melanoma incidence has declined in some younger age groups in Australia, including among people with high risk ancestry. Social and behavioural changes over the same period that lead to lower levels of ultraviolet radiation exposure probably contributed to these changes.

Expression of LOXL3, NES, and SNAI1 in Melanoma Genesis and Progression.

Melanoma is the most severe type of skin cancer and among the most malignant neoplasms in humans. With the growing incidence of melanoma, increased numbers of therapeutic options, and the potential to target specific proteins, understanding the basic mechanisms underlying the disease's progression and resistance to treatment has never been more important. LOXL3, SNAI1, and NES are key factors in melanoma genesis, regulating tumor growth, metastasis, and cellular differentiation. In our study, we explored the potential role of LOXL3, SNAI1, and NES in melanoma progression and metastasis among patients with dysplastic nevi, melanoma in situ, and BRAF+ and BRAF- metastatic melanoma, using immunofluorescence and qPCR analysis. Our results reveal a significant increase in LOXL3 expression and the highest NES expression in BRAF+ melanoma compared to BRAF-, dysplastic nevi, and melanoma in situ. As for SNAI1, the highest expression was observed in the metastatic melanoma group, without significant differences among groups. We found co-expression of LOXL3 and SNAI1 in the perinuclear area of all investigated subgroups and NES and SNAI1 co-expression in melanoma cells. These findings suggest a codependence or collaboration between these markers in melanoma EMT, suggesting new potential therapeutic interventions to block the EMT cascade that could significantly affect survival in many melanoma patients.

Higher subfoveal choroidal thickness in choroidal melanomas than in choroidal nevi.

To compare subfoveal choroidal thickness (SFCT) between eyes with choroidal melanoma and choroidal nevi. Retrospective study of 126 consecutive patients in a tertiary ocular oncology center. Eyes with tumors located less than two disc-diameters from the fovea were excluded. In eyes with naevi, factors of potential transformation into melanoma were recorded (orange pigment, subretinal fluid, thickness >2 mm, diameter >5 mm, ultrasound hollowness). SFCT was assessed by 3 independent observers on horizontal spectral-domain OCT scans. Sixty-seven eyes with choroidal melanoma and 59 eyes with choroidal nevi were included. The melanoma and nevi groups did not differ in gender (P=0.14) nor age (P=0.34). There was a very good agreement between the three independent observers for SFCT measurements (intraclass correlation coefficient=0.89). Mean SFCT was higher in melanomas (294.3±89.9 µm) than naevi (260.3±76.7 µm) (P=0.013), and the difference remained significant between melanomas and 28 naevi with ≥2 growth risk factors (256.3±77.0 µm) (P=0.027). In a multivariate model, the significant contributors to SFCT were presence of melanoma (P=0.004), younger age (P<0.0001) and shorter lesion distance to the fovea (P=0.016). SFCT may reflect the interplay between melanocytic tumors and their choroidal microenvironment. Its clinical utility should be explored in future studies.

Variations in vertebral muscle mass and muscle quality in adult patients with different types of cancer

ObjectivesAssessment of malnutrition-related muscle depletion with computed tomography (CT) using skeletal muscle index (SMI) and muscle radiation attenuation (MRA) at the third lumbar vertebra is well validated. However, SMI and MRA values at other vertebral locations and interchangeability as parameters in different types of cancer are less known. We aimed to investigate whether adult patients with different types of cancer show differences in SMI and MRA at all vertebral levels. MethodsWe retrospectively analyzed CT images from 203 patients:120 with head and neck cancer, esophageal cancer, or lung cancer (HNC/EC/LC) and 83 with melanoma (ME). Univariate and multivariate linear regression analyses determined the association between SMI (cm²/m2) and MRA (Hounsfield units) and cancer type at each vertebral level (significance corrected for multiple tests, P ≤ 0.002). The multivariate analyses included age, sex, cancer stage, comorbidity, CT protocol, and body mass index (BMI) (MRA analyses). ResultsSMI was lower in the HNC/EC/LC group versus the ME group at all vertebral levels, except C4 through C6 in the multivariate analyses. Female sex was associated with lower SMI at almost all levels. MRA was similar at most vertebral levels in both cancer groups but was lower at C1 through C4, T7, and L5 in the multivariate analyses. Use of contrast fluid and BMI were associated with higher MRA at all vertebral levels except T8 to T9 and C1 to C2, respectively. ConclusionsSMI, but not MRA, was lower in HNC/EC/LC patients than in ME patients at most vertebral levels. This indicates that low muscle mass presents itself across the various vertebral muscle areas. MRA may less consistently mark muscle depletion in malnourished patients.

Access to systemic treatment of non-melanoma skin cancer in Spain: a survey analysis.

Novel and highly effective drugs for non-melanoma skin cancer (NMSC) improve patient outcomes, but their high cost strains healthcare systems. Spain's decentralized public health system, managed by 17 autonomous communities (AaCc), raises concerns about equitable access. A cross-sectional survey (July-September 2023) was sent to Spanish Multidisciplinary Melanoma Group (GEM Group) members to assess access to new drugs. Fifty physicians from 15 Spanish AaCc responded to the survey. Access for drug with approved public reimbursement, Hedgehog inhibitors in basal-cell carcinoma and anti PD-L1 antibody in Merkel carcinoma, was observed in 84% and 86% of centers, respectively. For other EMA-approved treatments, but without reimbursement in Spain access decreased to 78% of centers. Heterogeneity in access was mainly observed intra regions. Unequal financial support for drugs for NMSC with creates a patchwork of access across Spanish hospitals, with variations even within the same AaCc.

PRAME and Historical Immunohistochemical Antibodies Ki-67, P16, and HMB-45 in Ambiguous Melanocytic Tumors.

Ambiguous melanocytic lesions/tumors (AMLs) can be simply described as melanocytic neoplasms that cannot be differentiated as either a melanoma or a nevus. Preferentially expressed antigen in melanoma (PRAME) is a novel antibody that can help differentiate between nevi and melanomas. However, its usefulness remains controversial in AMLs. The aim of this study was to demonstrate the importance of PRAME and diagnostic auxiliary antibodies (Ki-67, p16, HMB-45) in the diagnosis of melanocytic lesions, especially in AMLs. This study included 52 ambiguous melanocytic lesions, 40 nevi, and 40 melanomas. All immunohistochemical studies were performed automatically using the Universal Alkaline Phosphatase Red Detection Kit. Different analytic approaches were used for each antibody based on the literature. Statistically, the multinomial forward stepwise elimination logistic regression analysis was used to create a statistical model to predict the diagnosis of melanocytic lesions based on clinical, morphological, and immunohistochemical data. PRAME positivity was very strong and diffuse in the melanoma group and statistically significantly higher than that of the AML and nevus groups. There was no statistically significant difference between the nevus and AML groups. The Ki-67 proliferation index and HMB-45 staining pattern provided valuable indications for distinguishing between these 3 groups. The P16 antibody was limited in supporting the differential diagnosis. Our statistical model showed that a high mitosis count, central pagetoid spread, and PRAME positivity increased the probability of melanoma against an AML diagnosis. This study showed the advantages of evaluating the PRAME antibody together with morphological features and other immunohistochemical markers (Ki-67 and HMB-45) in the differential diagnosis of melanocytic lesions.

Advanced stage melanoma during pregnancy: Real-world management.

9540 Background: Treatment (tx) of advanced melanoma during pregnancy represents a major challenge. While management of early-stage melanoma is similar to non-pregnant patients (pts), very little data is available on outcome or tx guidelines for pregnant pts with advanced stage. Therefore, we collected real world management data, to ultimately develop management guidelines for these pts. Methods: This retrospective, international, multicenter database, included pts who either were diagnosed with advanced melanoma (newly diagnosed or recurrent) during pregnancy (group 1) or conceived while on systemic tx for melanoma (group 2) between 01/2011–06/2023. Patient, primary tumor and advanced melanoma characteristics, intervention/tx during pregnancy, and outcomes of mother and fetus were collected using a standardized, de-identified form. Results: 68 pts from 7 countries were included, with a total of 72 pregnancies: 60 pregnancies in group 1 and 12 in group 2, including 5 twin pregnancies. Median age at time of pregnancy was 32 (19-42). In group 1, advanced melanoma diagnosis occurred during the 1st trimester in 38%, followed by 3rd (32%), 2nd (22%) and unknown (8%) trimester. 2% had stage II melanoma, 48% stage III, and 50% stage IV. 76% were cutaneous melanoma, 7% mucosal, and 17% other subtypes. BRAF mutations were seen in 70%. Pregnancy was terminated in 15% of cases, and miscarriage occurred in 1 case. Of the 50 live births, 68% were induced and 56% were preterm (38% vaginal, 54% C-section). Median gestational age (MGA) was 34 wks (27-40). Systemic tx was initiated during pregnancy in 8 pts (targeted therapy [TT, 63%], immunotherapy [IT, 37%]). 90% switched or initiated new systemic tx after pregnancy (median time to start of therapy: 28 days; IT 65%, TT 27%, chemo 8%). 5-year overall survival (OS) was 49% (95%CI 34-69), with a median follow-up (MFU) of 26m. In group 2, 82% had cutaneous melanoma and 18% an unknown primary. 91% had a BRAF mutation. 42% of pts received systemic tx for stage III melanoma and 58% for stage IV (IT 75%, TT 25%). 33% of pregnancies were terminated, 8% ended in miscarriage. Of the 8 live births, 43% were preterm, 29% were induced (43% vaginal, 29% C-section). MGA was 35 wks (32-39). Half the pts initiated new or continued tx after pregnancy (IT 50%, TT 50%). 5-year OS was 78% (95%CI 55-100), with MFU of 48m. Of the 57 live births, 1 child born at 26w died after 3 days. No children developed melanoma, despite 5 placentas with melanoma involvement. 4 unexposed children had congenital deficits: prematurity-related (n=3) and congenital hypothyroidism (n=1). 1 child with 3rd trimester Vemurafenib exposure had heart malformations, and 2 experienced toxicity after in uteroIT exposure. Conclusions: This is the largest contemporary dataset of pts diagnosed with advanced melanoma during pregnancy and pts who became pregnant on systemic melanoma therapy, and provides a basis for developing clinical guidelines for this challenging population.

Access to melanoma drugs in Spain: a cross-sectional survey.

The development of highly active drugs has improved the survival of melanoma patients, but elevated drug prices place a significant burden on health care systems. In Spain, the public health care system is transferred to the 17 autonomous communities (AACC). The objective of this study is to describe the situation of drug access for melanoma patients in Spain and how this decentralized system is affecting equity. From July to September 2023, a cross-sectional survey was sent to members of the Spanish Multidisciplinary Melanoma Group (GEM Group). The questionnaire consulted about the real access to new drugs in each hospital. The responses were collected anonymously and analyzed according to several variables, including the AACC. The survey was answered by 50 physicians in 15 AACC. No major differences on access between AACC were observed for indications that are reimbursed by the Spanish Health Care System (adjuvant immunotherapy for stage IIIC-IIID and resected stage IV melanoma). Important differences in drug access were observed among AACC and among centers within the same AACC, for most of the EMA indications that are not reimbursed (adjuvant immunotherapy for stages IIB-IIC-IIIA-IIIB) or that are not fully reimbursed (ipilimumab plus nivolumab in advanced stage). Homogeneously, access to adjuvant targeted drugs, TIL therapy and T-VEC, is extremely low or non-existing in all AACC. For most indications that reimbursement is restricted out of the EMA indication, a great diversity on access was found throughout the different hospitals in Spain, including heterogeneity intra-AACC.

SEOM-GEM clinical guidelines for cutaneous melanoma (2023)

Cutaneous melanoma incidence is rising. Early diagnosis and treatment administration are key for increasing the chances of survival. For patients with locoregional advanced melanoma that can be treated with complete resection, adjuvant—and more recently neoadjuvant—with targeted therapy—BRAF and MEK inhibitors—and immunotherapy—anti-PD-1-based therapies—offer opportunities to reduce the risk of relapse and distant metastases. For patients with advanced disease not amenable to radical treatment, these treatments offer an unprecedented increase in overall survival. A group of medical oncologists from the Spanish Society of Medical Oncology (SEOM) and Spanish Multidisciplinary Melanoma Group (GEM) has designed these guidelines, based on a thorough review of the best evidence available. The following guidelines try to cover all the aspects from the diagnosis—clinical, pathological, and molecular—staging, risk stratification, adjuvant therapy, advanced disease therapy, and survivor follow-up, including special situations, such as brain metastases, refractory disease, and treatment sequencing. We aim help clinicians in the decision-making process.

Five-year analysis of neoadjuvant dabrafenib and trametinib for stage III melanoma

Five-year analysis of neoadjuvant dabrafenib and trametinib for stage III melanoma

Stressful life events and the occurrence of skin cancer.

It is widely acknowledged that emotional states can influence skin conditions, yet limited research has delved into the impact of stress on skin cancer development. This retrospective study sought to expand the perspective on skin cancer risk factors by investigating the complex relationship between stressful life events and the incidence of skin cancer. The sample included 268 individuals followed-up in a dermatological clinic, in three groups: Patients who had previously been diagnosed with cutaneous melanoma and are currently in remission (32%), those who had been diagnosed with non-melanoma skin cancer (30%), and a control group who are at risk for skin cancer (38%). Participants filled in questionnaires regarding childhood and adulthood life events, and loss and gain of resources following their subjectively most stressful event in adulthood. Multinomial logistic regression was used to examine the associations of life events with skin cancer occurrence, and mediating and moderating effects of resource loss/gain. Adverse childhood experiences were associated with melanoma occurrence, with the melanoma group reporting significantly more such experiences compared to the control group (p<0.001). Resource loss from subjectively significant stressful life events in adulthood partially mediated the association between adverse childhood experiences and melanoma incidence. The findings suggest that there may be intricate connections between stress, life events, adaptation to change, and skin cancer, which future research may further unravel. This study underscores the need for a more comprehensive approach to stress management, coping strategies development, and skin cancer prevention in healthcare settings.

A General Approach to Patients Presenting With Locally Advanced or Distant Metastatic Disease.

The widespread adoption of immune checkpoint inhibitors and small molecule inhibitors of the MAP kinase pathway has transformed the management of locally advanced and metastatic melanoma. Here, we provide a broad overview on the use of these agents in the first-line setting, incorporating a review of the clinical literature as well as the practice patterns of our respective melanoma groups. Throughout, we highlight areas of uncertainty that provide opportunities for future clinical investigation and additional improvement in outcomes for patients with melanoma.

Analysis of the dermoscopic features of excised melanomas and their relation with tumor thickness in a tertiary hospital in Brazil.

Dermoscopy is a non-invasive, cost-effective tool useful in the assessment of pigmented lesions. The aim of this study was to analyze the dermoscopic features in excised melanomas in a tertiary hospital in Brazil and the influence of Breslow thickness on the dermoscopic features observed. An observational, cross-sectional study in which dermoscopic images of 43 melanomas were evaluated. The patients were divided into three groups: in situ, thin invasive melanoma (Breslow thickness <1 mm), and thick invasive melanoma (Breslow thickness ≥1 mm). We studied 33 patients with 43 melanomas. Twenty-one (48.8%) were melanoma in situ, 16 (37.2%) were thin melanomas, and 6 (14%) were thick melanomas. The most frequent dermoscopic criteria observed in all cases were atypical pigment network, multiple colors (3 or more), asymmetrical blotches, and peripheral asymmetric dots and globules. There was a statistically significant difference in the three groups regarding the frequency of atypical vessels, white scar areas, blue-white veil, shiny white structures, and radial streaming. The group of invasive melanomas presented with a higher frequency and statistical significance (P < 0.05) of atypical vessels, white scar areas, blue-white veil, and shiny white structures when compared to in situ melanomas. The presence of radial streaming and blue-white veil was more frequent in thick invasive melanomas than in thin invasive melanomas. The presence of a higher number of structures was seen in invasive melanomas, with a median of 5 and 7.5 structures for thin and thick invasive tumors, respectively. In line with prior data, we identified an association between invasive melanomas and structures linked to fibrosis and tumor vascularity. Specifically, we noted the presence of atypical vessels, scar-like white areas, a blue-white veil, and shiny white structures. Also, a higher number of dermoscopic structures was seen in invasive melanomas. In thicker melanomas, we observed additional findings, including a higher frequency of radial streaming and a blue-white veil.

Morphometric differences between basal cell carcinomas & melanomas of the head & neck versus other sites and their influence on neural networks

BackgroundDermoscopic appearance of basal cell carcinomas (BCC) and melanomas guide diagnosis and may be influenced by anatomic location. ObjectiveWe aimed to investigate the morphometric differences between anatomic sites of the head and neck(H&N) versus other body sites in basal cell carcinomas and melanomas and how these differences may impact neural network model accuracy. MethodsMorphometric image analysis of the BCCs(n=422) and melanomas(n=868) from the publicly available HAM10000 dataset was performed using an open-source image analysis software. Univariate and multivariate statistical analysis was done to identify differences between H&N and other anatomic sites. The multifactorial data was further interrogated with dimensionality reduction techniques. Randomly generated neural networks with different anatomic proportions of training data were used to assess how these features influence diagnostic accuracy. ResultsFifty-three univariate and 11 multivariate features were found to be statistically significant in the BCC group(P<0.05). Thirteen univariate and 8 multivariate features were statistically significant in the melanoma group(P<0.05). Dimensionality reduction via linear discriminant analysis of the BCC groups revealed modest separation of the data by anatomical site. Melanomas appeared to be more homogenous across anatomic sites. Morphometric features significantly influenced neural network accuracies in classifying BCCs, with a mix of H&N and other site training data resulting in the best models(P<0.05). ConclusionMorphometric features and the anatomic composition of BCC training data may influence the accuracy of AI models. Model developers should be aware of the anatomic distribution of their training datasets and report site-specific validation metrics.

Targeted Therapy and Immunotherapy for Advanced Malignant Conjunctival Tumors: Systematic Review.

To review the outcomes of targeted therapy and immunotherapy in advanced conjunctival tumors, including conjunctival squamous cell carcinoma, conjunctival melanoma, and conjunctival lymphoma. A Pubmed database systematic search was performed between January 1999 and December 2022. The literature search was limited to studies published in English. This review included 142 patients with advanced malignant conjunctival tumors from 42 articles. In the conjunctival squamous cell carcinoma group, 2 cases of advanced conjunctival squamous cell carcinoma treated with epidermal growth factor receptor inhibitors showed significant tumor size improvement after 7.5 months of follow-up. Among 7 cases treated with systemic immunotherapy, 5 cases (72%) had complete response (CR), 1 case (14%) showed partial response (PR), and 1 case (14%) had stable disease (SD) after 16 months. In the conjunctival melanoma group, among 18 cases treated with combined v-raf murine sarcoma viral oncogene homolog B1/mitogen-activated extracellular signal-regulated kinase inhibitors, 6 (33%) had CR, 5 (28%) had PR, 2 (11%) had SD, and 5 (28%) had progressive disease after 24.8 months of follow-up. Of 44 conjunctival melanoma cases treated with immunotherapy, 12 (28%) had CR, 9 (20%) had PR, 7(16%) had SD, and 16 (36%) had progressive disease after 14.2 months. Systemic Rituximab treatment for conjunctival lymphoma cases resulted in CR in 21 patients (63%), PR in 11 patients (33%), and SD in 1 patient (3%) after 20.5 months of follow-up. Intralesional Rituximab injections in 38 conjunctival lymphoma cases showed CR in 28 patients (75%), PR in 7 patients (19%), SD in 1 patient (2%), and progressive disease in 2 patients (4%) after 20.4 months of follow-up. Despite limited clinical case reports and short-term follow-ups, targeted therapy and immunotherapy have shown promising results for advanced malignant conjunctival tumors.

Continuous topical application of microencapsulated recombinant human epidermal growth factor does not promote the progression of established melanoma in animals

Microencapsulated epidermal growth factor (EGF) device has been applied topically for the management of several types of wounds to accelerate wound healing and prevent scar formation. However, it remains unclear whether such EGF device induced neoplastic transformation in the skin. In this study, we exploited a well-established murine B16-F10 melanoma model, coupled with MTT viability and colony formation assays, to investigate the influence of microencapsulated recombinant EGF (Me-EGF; brand name NewEpi&amp;reg;) and its ingredients on the tumorigenicity of skin cancer cells in vitro and in vivo. The results indicated that Me-EGF did not stimulate the viability nor the anchorage-dependent growth of B16-F10 melanoma cells. Western blot analysis showed that Me-EGF treatment increased the total and phosphorylated EGFR expression without affecting the HER2 expression in B16-F10 melanoma cells. In mice bearing established B16-F10 melanoma, continuous application of Me-EGF for 14 days did not enhance the melanoma tumor burden compared with control groups. Immunohistochemical analysis also revealed the similar expression of proliferative index Ki-67 between Me-EGF-treated melanoma and other groups. Altogether, these results suggest that the application of Me-EGF device did not promote the oncogenic potential of B16-F10 melanoma in vitro and in vivo.

PRAME expression in 137 primary cutaneous melanomas and comparison with 38 related metastases

Melanocytic lesions have always represented a diagnostic challenge for surgical pathologists. According to the literature, PRAME showed great promise as an immunohistochemical tool in the distinction between benign and malignant melanocytic lesions. In the present study, we retrospectively analyzed 137 thicker (Breslow > 1 mm) primary cutaneous melanomas with the aim to better understand the utility of PRAME immunohistochemistry in daily practice and also to investigate if PRAME could represent a prognostic biomarker for cutaneous melanomas. PRAME immunohistochemistry was performed in all melanomas and in the metastases with antibodies to PRAME (dilution 1:1000, clone Ab219650) on an automated immunostainer (Ventana Benchmark Ultra) using a brown chromogen (DAB). We found that melanomas (59.1%) show diffuse PRAME expression (score 4 +). 99 (72.3%) primary cutaneous melanoma had no relapse during the follow-up. Of this group of melanomas, 61/99 (61.6%) were diffusely positive for PRAME. 38 (27.7%) primary cutaneous melanoma had relapses. Of this group, 28/36 (77.7%) were diffusely positive. We did not find any statistical correlation between diffuse PRAME expression and the presence of driver mutation in BRAF gene (p = 0.927), NRAS gene (p = 0.496) or either of the two (p = 0.138). We did not find a prognostic significance of diffuse PRAME expression for relapse (p = 0.462) or survival rate (p = 0.245). The prognostic value of PRAME has been only reported in mucosal, uveal and cutaneous thin melanomas. Here, we show statistical analyses on PRAME expression for melanoma with Breslow > 1 mm based on survival rate and long-term follow-up. According to our results, PRAME is a useful immunohistochemical ancillary tool in daily practice diagnosis of melanocytic lesions.

Diagnostic utility of combining PRAME and HMB-45 stains in primary melanocytic tumors

BackgroundPathologists face ongoing challenges distinguishing between benign and malignant melanocytic tumors. PRAME (PReferentially expressed Antigen in Melanoma) has a demonstrated value distinguishing between these types of lesions. However, the sensitivity of single immunohistochemistry is variable. HMB-45 is another valuable marker, but on its own, has a limited ability in setting of primary melanocytic tumors. This study sought to evaluate the diagnostic potential of a dual panel combining PRAME and HMB-45 in the assessment of primary melanocytic tumors. Methods259 tumors, of which 141 were benign nevi, 31 dysplastic nevi (either low- or high grade dysplasia), and further 87 malignant melanomas, were retrieved from the department's archives and assessed by two experienced dermatopathologists. New sections were stained with PRAME and HMB-45, respectively. For PRAME, a nuclear, and for HMB-45, a cytoplasmic staining, was considered positive and scored as described in the literature on a scale from 0 to 4+. Only dermal component was assessed on HMB-45 stain. ResultsPRAME was diffusely expressed in only 1 benign nevus, with focal expression in further 28 compared to 22 diffusely and 103 focally HMB-45-positive benign nevi. 5 high-grade dysplastic nevi showed diffuse PRAME expression in epidermal component, with varying degree of positivity in adjacent dermal compartment, and further 8 dysplastic nevi showed only focal expression. HMB-45 was diffusely expressed in only 2, with focal expression in 23, and no apparent positivity in remaining 6 dysplastic nevi. In invasive melanoma group, PRAME stained >75 % cells in 64/87 tumors, however, 10/87 melanomas were completely negative. HMB-45 was captured diffusely in 49/87 melanomas, 32 showed patchy expression, and 6 tumors were blank negative. Diffuse 4+ PRAME positivity showed superior sensitivity and specificity of 73,6 % and 96,5 %, respectively, compared to HMB-45, 56,3 % and 86,0 %, respectively. No nevi showed double 4+ positivity, however, the sensitivity for double positivity was only 49,4 %. ConclusionOur results confirm the superiority of PRAME over HMB-45 in the differential diagnosis of melanocytic tumors. However, combined staining can significantly increase specificity, rendering a benign diagnosis more unlikely in a double 4+ diffuse positivity setting.