The Complex Interplay between Nevi and Melanoma: Risk Factors and Precursors

Risk Prediction Models for Sentinel Node Positivity in Melanoma: A Systematic Review and Meta-Analysis

Importance

There is a need to identify the best performing risk prediction model for sentinel lymph node biopsy (SLNB) positivity in melanoma.

Objective

To comprehensively review the characteristics and discriminative performance of existing risk prediction models for SLNB positivity in melanoma.

Data Sources

Embase and MEDLINE were searched from inception to May 1, 2024, for English language articles.

Study Selection

All studies that either developed or validated a risk prediction model (defined as any calculator that combined more than 1 variable to provide a patient estimate for probability of melanoma SLNB positivity) with a corresponding measure of model discrimination were considered for inclusion by 2 reviewers, with disagreements adjudicated by a third reviewer.

Data Extraction and Synthesis

Data were extracted in duplicate according to Data Extraction for Systematic Reviews of Prediction Modeling Studies, Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis, and Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guidelines. Effects were pooled using random-effects meta-analysis.

Main Outcome and Measures

The primary outcome was the mean pooled C statistic. Heterogeneity was assessed using the I2 statistic.

Results

In total, 23 articles describing the development of 21 different risk prediction models for SLNB positivity, 20 external validations of 8 different risk prediction models, and 9 models that included sufficient information to obtain individualized patient risk estimates in routine preprocedural clinical practice were identified. Among all risk prediction models, the pooled weighted C statistic was 0.78 (95% CI, 0.74-0.81) with significant heterogeneity (I2 = 97.4%) that was not explained in meta-regression. The Memorial Sloan Kettering Cancer Center and Melanoma Institute of Australia models were most frequently externally validated with both having strong and comparable discriminative performance (pooled weighted C statistic, 0.73; 95% CI, 0.69-0.78 vs pooled weighted C statistic, 0.70; 95% CI, 0.66-0.74). Discrimination was not significantly different between models that included gene expression profiles (pooled C statistic, 0.83; 95% CI, 0.76-0.90) and those that only used clinicopathologic features (pooled C statistic, 0.77; 95% CI, 0.73-0.81) (P = .11).

Conclusions and Relevance

This systematic review and meta-analysis found several risk prediction models that have been externally validated with strong discriminative performance. Further research is needed to evaluate the associations of their implementation with preprocedural care.

Predicting BRAF Mutations in Cutaneous Melanoma Patients Using Neural Network Analysis

Point mutations at codon 600 of the BRAF oncogene are the most common alterations in cutaneous melanoma (CM). Assessment of BRAF status allows to personalize patient management, though the affordability of molecular testing is limited in some countries. This study aimed to develop a model for predicting alteration in BRAF based on routinely available clinical and histological data. Methods: For identifying the key factors associated with point mutations in BRAF, 2041 patients with CM were recruited in the study. The presence of BRAF mutations was an endpoint. The variables included demographic data (gender and age), anatomic location, stage, histological subtype, number of mitosis, and also such features as ulceration, Clark level, Breslow thickness, infiltration by lymphocytes, invasiveness, regression, microsatellites, and association with nevi. Results: A relatively high rate of BRAF mutation was revealed in the Ukrainian cohort of patients with CM. BRAF-mutant melanoma was associated with younger age and location of nonsun-exposed skin. Besides, sex-specific differences were found between CM of various anatomic distributions and the frequency of distinct BRAF mutation subtypes. A minimal set of variables linked to BRAF mutations, defined by the genetic input selection algorithm, included patient age, primary tumor location, histological type, lymphovascular invasion, ulceration, and association with nevi. To encounter nonlinear links, neural network modeling was applied resulting in a multilayer perceptron (MLP) with one hidden layer. Its architecture included four neurons with a logistic activation function. The AUROCMLP6 of the MLP model comprised 0.79 (95% CІ: 0.74-0.84). Under the optimal threshold, the model demonstrated the following parameters: sensitivity: 89.4% (95% CІ: 84.5%-93.1%), specificity: 50.7% (95% CІ: 42.2%-59.1%), positive predictive value: 73.1% (95% CІ: 69.6%-76.3%), and negative predictive value: 76.0% (95% CІ: 67.6%-82.8%). The developed MLP model enables the prediction of the mutation in BRAF oncogene in CM, alleviating decisions on personalized management of patients with CM. In conclusion, the developed MLP model, which relies on the assessment of 6 variables, can predict the BRAF mutation status in patients with CM, supporting decisions on patient management.

The potential of x-ray virtual histology in the diagnosis of skin tumors

BACKGROUND

Histopathological analysis represents the gold standard in clinical practice for diagnosing skin neoplasms. While the current diagnostic workflow has specialized in producing robust and accurate results, interpreting tissue architecture and malignant cellular morphology correctly remains one of the greatest challenges for pathologists. This paper aims to explore the prospect of applying x-ray virtual histology to human skin tumor excisions and correlating it with the histological validation.

MATERIALS AND METHODS

Seven skin biopsies containing intriguing melanoma types and pigmented skin lesions were scanned using x-ray Computed micro-Tomography (μCT) and then sectioned for conventional histology assessment.

RESULTS

The tissue microarchitecture reconstructed by μCT offers detailed insights into diagnosing the malignancy or benignity of the skin lesions. Three-dimensional reconstruction via x-ray virtual histology reveals infiltrative patterns in basal cell carcinoma and evaluated invasiveness in melanoma. The technology enables the identification of pagetoid distributions of neoplastic cells and the assessment of melanoma depth in three dimensions.

CONCLUSION

Although the proposed approach is not intended to replace conventional histology, the non-destructive nature of the sample and the clarity provided by virtual inspection demonstrate the promising impact of μCT as a valid support method prior to conventional histological sectioning. Indeed, μCT images can suggest the optimal sectioning position before using a microtome, as is commonly performed in histological practice. Moreover, the three-dimensional nature of the proposed approach paves the way for a more accurate assessment of significant prognostic factors in melanoma, such as Breslow thickness, by considering the whole micro-volume rather than a two-dimensional observation.

Nevi and Melanoma in Children: What to Do in Daily Medical Practice: Encyclopedia for Pediatricians and Family Doctors

Melanocytic nevi, commonly known as moles, are benign skin lesions that often occur in children and adolescents. Overall, they are less common in children compared to adults. Understanding the diagnosis and management of melanocytic nevi and risk factors for melanoma development is crucial for their early detection and appropriate treatment. This paper presents children's most common melanocytic nevi, including their epidemiology, morphology, diagnostic methods, and treatment.

Changes in mucosa‑associated lymphoid tissue 1 predicts therapeutic response and survival in patients with advanced melanoma receiving programmed cell death‑1 inhibitor monotherapy

Advanced melanoma is an aggressive and dangerous form of skin cancer, and programmed cell death-1 (PD-1) inhibitors are recommended treatment options for patients with advanced melanoma. Mucosa-associated lymphoid tissue 1 (MALT1) impairs CD8+ T-cell activation to induce immune escape, leading to a reduction in the antitumor effect of PD-1 inhibitors. The present study aimed to assess the prognostic implication of MALT1 in patients with advanced melanoma receiving PD-1 inhibitor monotherapy. Blood MALT1 levels were assessed using reverse transcription-quantitative PCR in 20 healthy controls (HCs) after enrollment and in 49 patients with advanced melanoma before (T0), as well as 2 months (T1) and 4 months after (T2) PD-1 inhibitor monotherapy. The maximum level of MALT1 in HCs (3.100) was used as the cut-off in patients with advanced melanoma. MALT1 levels at T0 were significantly increased in patients with advanced melanoma compared with in HCs (P<0.001). In patients with advanced melanoma, MALT1 was significantly decreased from T0 to T2 (P<0.001). Objective response rate (ORR) and disease control rate (DCR) were 28.6 and 59.2%, respectively. MALT1 levels at T1 were significantly negatively associated with overall therapeutic response (P=0.001), ORR (P=0.009) and DCR (P=0.004). MALT1 levels at T2 were significantly inversely associated with overall therapeutic response (P=0.021) and ORR (P=0.036). Moreover, MALT1 levels >3.100 at T0 (P=0.027) and T1 (P=0.045) were significantly associated with shorter progression-free survival (PFS), and MALT1 levels >3.100 at T1 were significantly associated with a poor overall survival (OS; P=0.022). Multivariate Cox regression analysis demonstrated that MALT1 levels at T0 (>3.100 vs. ≤3.100) were significantly associated with a poor PFS [hazard ratio (HR)=2.248; P=0.037], and MALT1 levels at T1 (>3.100 vs. ≤3.100) were significantly associated with a poor OS (HR=4.332; P=0.007). In conclusion, MALT1 levels are reduced following PD-1 treatment, and a high MALT1 level is associated with a poor therapeutic response and shorter survival in patients with advanced melanoma receiving PD-1 inhibitor monotherapy.

Nevus-associated Lentigo Maligna and Lentigo Maligna Melanoma, Clinicopathological Features

Nevus-associated lentigo maligna and lentigo maligna melanoma (NALMM) are rarely described in the literature and are considered an incidental finding. This study aimed to evaluate the frequency of NALMM and its clinicopathological features. A total of 201 histopathology reports were reviewed and among them 20% of the samples corresponded to NALMM, with females overrepresented in this group (p = 0.02). A significant association was also observed between NALMM with the presence of multiple nevi (p = 0.01), and dysplastic nevi (p = 0.04). Moreover, the risk of developing a second melanoma of nevus-associated type was 4.3 times higher in patients with NALMM. These results indicate that NALMM is more frequent than previously reported, suggesting that the associated nevus could interact or even act as a precursor for LM/LMM. Future studies with larger samples allied to techniques like confocal microscopy and molecular analysis are essential to determine this biological link between nevus and LM/LMM.

The Keratinocyte in the Picture Cutaneous Melanoma Microenvironment

Melanoma progression is a multistep evolution from a common melanocytic nevus through a radial superficial growth phase, the invasive vertical growth phase finally leading to metastatic dissemination into distant organs. Melanoma aggressiveness largely depends on the propensity to metastasize, which means the capacity to escape from the physiological microenvironment since tissue damage due to primary melanoma lesions is generally modest. Physiologically, epidermal melanocytes are attached to the basement membrane, and their adhesion/migration is under the control of surrounding keratinocytes. Thus, the epidermal compartment represents the first microenvironment responsible for melanoma spread. This complex process involves cell-cell contact and a broad range of secreted bioactive molecules. Invasion, or at the beginning of the microinvasion, implies the breakdown of the dermo-epidermal basement membrane followed by the migration of neoplastic melanocytic cells in the superficial papillary dermis. Correspondingly, several experimental evidences documented the structural and functional rearrangement of the entire tissue surrounding neoplasm that in some way reflects the atypia of tumor cells. Lastly, the microenvironment must support the proliferation and survival of melanocytes outside the normal epidermal-melanin units. This task presumably is mostly delegated to fibroblasts and ultimately to the self-autonomous capacity of melanoma cells. This review will discuss remodeling that occurs in the epidermis during melanoma formation as well as skin changes that occur independently of melanocytic hyperproliferation having possible pro-tumoral features.

Melanoma biology and treatment: a review of novel regulated cell death-based approaches

The incidence of melanoma, the most lethal form of skin cancer, has increased due to ultraviolet exposure. The treatment of advanced melanoma, particularly metastatic cases, remains challenging with poor outcomes. Targeted therapies involving BRAF/MEK inhibitors and immunotherapy based on anti-PD1/anti-CTLA4 antibodies have achieved long-term survival rates of approximately 50% for patients with advanced melanoma. However, therapy resistance and inadequate treatment response continue to hinder further breakthroughs in treatments that increase survival rates. This review provides an introduction to the molecular-level pathogenesis of melanoma and offers an overview of current treatment options and their limitations. Cells can die by either accidental or regulated cell death (RCD). RCD is an orderly cell death controlled by a variety of macromolecules to maintain the stability of the internal environment. Since the uncontrolled proliferation of tumor cells requires evasion of RCD programs, inducing the RCD of melanoma cells may be a treatment strategy. This review summarizes studies on various types of nonapoptotic RCDs, such as autophagy-dependent cell death, necroptosis, ferroptosis, pyroptosis, and the recently discovered cuproptosis, in the context of melanoma. The relationships between these RCDs and melanoma are examined, and the interplay between these RCDs and immunotherapy or targeted therapy in patients with melanoma is discussed. Given the findings demonstrating melanoma cell death in response to different stimuli associated with these RCDs, the induction of RCD shows promise as an integral component of treatment strategies for melanoma.

A Narrative Review of Current Knowledge on Cutaneous Melanoma

Cutaneous melanoma is a public health problem. Efforts to reduce its incidence have failed, as it continues to increase. In recent years, many risk factors have been identified. Numerous diagnostic systems exist that greatly assist in early clinical diagnosis. The histopathological aspect illustrates the grim nature of these cancers. Currently, pathogenic pathways and the tumor microclimate are key to the development of therapeutic methods. Revolutionary therapies like targeted therapy and immune checkpoint inhibitors are starting to replace traditional therapeutic methods. Targeted therapy aims at a specific molecule in the pathogenic chain to block it, stopping cell growth and dissemination. The main function of immune checkpoint inhibitors is to boost cellular immunity in order to combat cancer cells. Unfortunately, these therapies have different rates of effectiveness and side effects, and cannot be applied to all patients. These shortcomings are the basis of increased incidence and mortality rates. This study covers all stages of the evolutionary sequence of melanoma. With all these data in front of us, we see the need for new research efforts directed at therapies that will bring greater benefits in terms of patient survival and prognosis, with fewer adverse effects.

Bitter Phytochemicals as Novel Candidates for Skin Disease Treatment

Skin diseases represent a global healthcare challenge due to their rising incidence and substantial socio-economic burden. While biological, immunological, and targeted therapies have brought a revolution in improving quality of life and survival rates for certain dermatological conditions, there remains a stringent demand for new remedies. Nature has long served as an inspiration for drug development. Recent studies have identified bitter taste receptors (TAS2Rs) in both skin cell lines and human skin. Additionally, bitter natural compounds have shown promising benefits in addressing skin aging, wound healing, inflammatory skin conditions, and even skin cancer. Thus, TAS2Rs may represent a promising target in all these processes. In this review, we summarize evidence supporting the presence of TAS2Rs in the skin and emphasize their potential as drug targets for addressing skin aging, wound healing, inflammatory skin conditions, and skin carcinogenesis. To our knowledge, this is a pioneering work in connecting information on TAS2Rs expression in skin and skin cells with the impact of bitter phytochemicals on various beneficial effects related to skin disorders.

Optically Guided High-Frequency Ultrasound Shows Superior Efficacy for Preoperative Estimation of Breslow Thickness in Comparison with Multispectral Imaging: A Single-Center Prospective Validation Study

Melanoma is the most aggressive form of skin cancer that is known for its metastatic potential and has an increasing incidence worldwide. Breslow thickness, which determines the staging and surgical margin of the tumor, is unavailable at initial diagnosis. Novel imaging techniques for assessing Breslow thickness lack comparative data. This study evaluates optically guided high-frequency ultrasound (OG-HFUS) and multispectral imaging (MSI) for preoperative estimation of Breslow thickness and staging. We enrolled 101 patients with histologically confirmed primary melanoma and categorized them based on tumor thickness. Optically guided 33 MHz HFUS and MSI were utilized for the assessment. Our MSI-based algorithm categorized melanomas into three subgroups with a sensitivity of 62.6%, specificity of 81.3%, and fair agreement (κ = 0.440, CI: 0.298-0.583). In contrast, OG-HFUS demonstrated a sensitivity of 91.8%, specificity of 96.0%, and almost perfect agreement (κ = 0.858, CI: 0.763-0.952). OG-HFUS performed better than MSI in estimating Breslow thickness, emphasizing its potential as a valuable tool for melanoma diagnosis and patient management. OG-HFUS holds promise for enhancing preoperative staging and treatment decision-making in melanoma.

[Fluorescence detection to diagnose melanoma : An alternative objective method for dermatohistology]

BACKGROUND

Dermatohistological assessment is the gold standard in the diagnosis of melanoma. As a subjective method, this depends, among other things, on the expertise of the examiner.

AIM

A new objective method of investigation-dermatohistofluoroscopy-aims to improve the diagnostic reliability of melanoma diagnosis.

MATERIALS AND METHODS

The ultra-weak spectrally resolved fluorescence of melanin of pigment-bearing skin cells is a reliable indicator of the malignancy of the tissue to be diagnosed. Using a special laser spectroscopic method, this fluorescence can be measured on histological specimen (and also on tissue in vivo and on excidate).

RESULTS AND DISCUSSION

Melanocytes from normally pigmented skin, nevomelanocytes from benign and dysplastic nevi, and melanoma cells each show characteristic, different fluorescence spectra. If these cell types are shown spatially resolved in different colors on the preparation to be diagnosed, they give the histologist an objective basis for the diagnosis, even in difficult cases, e.g., the so-called stumbling blocks of melanoma diagnosis such as Spitzoid tumors. Currently, the method can only be used for Fitzpatrick skin types 1 and 2. In addition, a separate second measurement signal at 400 nm can be used to identify tumor breakthrough through the basement membrane. This signal is collagen bound, so it also appears in amelanotic melanomas, to which the method is otherwise inherently inapplicable.