Large congenital melanocytic nevi and the risk for development of malignant melanoma and neurocutaneous melanocytosis

Metabolomic analysis reveals the biological characteristics of giant congenital melanocytic nevi

Giant congenital melanocytic nevi (GCMN) is a congenital cutaneous developmental deformity tumor that usually occurs at birth or in the first few weeks after birth, but its pathogenesis is still unclear. In this study, nuclear magnetic resonance-based metabolomics strategy was employed to evaluate the metabolic variations in serum and urine of the GCMN patients in order to understand its underlying biochemical mechanism and provide a potential intervention idea. Twenty-nine metabolites were observed to change significantly in serum and urine metabolomes, which are mainly involved in a variety of metabolic pathways including glyoxylate and dicarboxylate metabolism, TCA cycle and metabolisms of amino acids. The substantial cores of all the disturbed metabolic pathways are related to amino acid metabolism and carbohydrate metabolism and regulate the physiological state of the GCMN patients. Our results provide the physiological basis and physiological responses of GCMN and will be helpful for better understanding the molecular mechanisms of GCMN in future research.

Melanoma on congenital melanocytic nevi

Among nevus-associated melanomas, which overall account for 20%-30% of all melanomas, those arising specifically in congenital melanocytic nevi are infrequent, but can be disproportionately frequent in childhood and adolescence. Congenital melanocytic nevi (CMNi) are common benign melanocytic tumors that are present at birth or become apparent in early childhood. They are classified based on the projected adult size. Small and medium-sized CMNi are frequent, whereas large/giant CMNi (over 20 cm in diameter) are rare, but can be associated with high morbidity due to marked aesthetic impairment and the risk of neurocutaneous syndrome or melanoma development. In this setting, melanomas can appear in early childhood and are very aggressive, while the risk of small-medium CMNi of developing melanoma is low and similar to non-congenital melanocytic nevi. Histologically, most melanomas on CMNi initiate their growth at the epidermal-dermal junction, but in large/giant CMNi they can develop entirely in the dermis, in deeper tissues, or in extracutaneous sites (especially in the central nervous system). Most CMNi harbour an NRAS mutation, but other genes are rarely involved, and gene translocations have recently been described. However, no prognostic implications have been associated with the CMN genotype. Melanomas developed on CMNi harbour additional molecular alterations to which the aggressive clinical course of these tumors has been attributed. This review covers the distinctive clinical and pathological aspects of melanomas on CMNi, and includes the epidemiology, etiopathogenesis, clinical and dermoscopic presentation, histological and molecular characteristics, as well as tumour behaviour.

Histopathological characteristics analysis of giant melanocytic naevi in children

BACKGROUND

The major diagnostic criterion for the giant congenital melanocytic nevus (GCMN) is a size larger than 20 cm in diameter. However, the histopathological origin, pathogenesis, and GCMN progression are not yet completely clear. Unlike other medium or small superficial lesions, histomorphological evaluation is significant for GCMN pathological classification, malignant transformation assessment, and early detection of prognosis.

AIMS

This study aimed to investigate the pathological features of GCMN, including its satellite lesions.

PATIENTS/METHODS

Twenty-three giant naevi and seventeen "satellite lesions" were collected from children aged 1 to 10 in Shanghai Ninth People's Hospital from 2018 to 2020. A histological study was conducted to evaluate their histological appearance. All the data observed and recorded data were statistically analyzed.

RESULTS

In 23 cases of GCMN primary nevus, nevus cells were mainly distributed in the dermal region, with melanocyte proliferation and the presence of nevus nests at the dermal-epidermal junction. However, in satellite nevus, a junctional growth pattern was noted. Additionally, other histopathologic features, including epidermal contour, cell morphology, and architecture disorder also showed significant differences between primary nevus and satellite nevus.

CONCLUSIONS

We demonstrated that the congenital pattern of the main nevus is more obvious than one of the satellite nevus, suggesting that the satellite nevus and the main nevus may occur slightly later than the main nevus. "Satellite nevus" happens as a result of a separate genetic event.

Neurocutaneous Melanosis with Meningeal Melanocytosis: A Rare Case of Intracranial Hypertension and Cutaneous Manifestations

A 50-year-old male presented to the emergency room after experiencing sudden right upper limb facial numbness and dysphasia, followed by full recovery. A brain CT scan showed hyperdense lesions within the left hemispheric sulcus, which raised suspicion of spontaneous subarachnoid hemorrhage. A T1-weighted MRI showed multiple tiny leptomeningeal enhancements in the same area, and a digital subtraction angiography showed no signs of vascular abnormality. Cerebrospinal fluid cytology revealed atypical melanin-containing cells with minimal pleomorphism. One month later, the patient developed sixth nerve palsy, which was determined to be due to intracranial hypertension. Multiple giant nevi on the legs, trunk, and scalp were also observed. A skin biopsy showed well-defined and symmetrical proliferation of melanocytic nevus cell nests in the dermis. An open biopsy was performed due to the suspicious leptomeningeal lesions, which surprisingly revealed diffuse and thick black-colored tissue infiltration of the leptomeninges. Pathology confirmed the diagnosis of meningeal melanocytosis. A ventriculoperitoneal shunt was then placed, and the patient's neurological symptoms gradually improved. Based on the presence of multiple giant nevi on the patient's skin and the finding of diffuse meningeal melanocytosis during the open biopsy, the patient was diagnosed with neurocutaneous melanosis. The patient received 6 cycles triweekly of Ipilimumab and Nivolumab 8 months after initial diagnosis. Unfortunately, the disease progressed and the patient passed away 14 months after initial diagnosis.

A clinical and biologic review of congenital melanocytic nevi

Congenital melanocytic nevi (CMN) are the result of aberrations in the mitogen-activated protein kinase signal transduction pathway caused by postzygotic somatic mutations. The estimated incidence of newborns with CMN is 1%-2%. The main complications of CMN include proliferative nodules, melanomas, and neurocutaneous melanosis, and the latter two are the most troublesome issues to address. Treatments are primarily taken into account for aesthetic purposes and the reduction of melanoma risk. Due to the much lower incidence of malignant transformation observed in recent studies than in previous data, clinical management paradigms for CMN patients have gradually shifted towards conservative observation and close monitoring. Surgery and lasers are still the main treatments, and targeted therapy may be a promising strategy to help manage complications. With the increase in awareness of mental health, increasing focus has been placed on the quality of life (QoL) and psychological issues of both CMN patients and their parents. Recent studies have revealed that families coping with CMN might endure intense pressure, a major loss in QoL, and psychological problems after diagnosis and during treatment. Here, we sought to present an overview of genetic basis, complications, treatments, and psychological issues related to CMN and hope to provide better management for patients with CMN.

Non-dysraphic extramedullary intradural spinal lipoma with neurocutaneous melanocytosis

INTRODUCTION

Intradural spinal lipomas are very rare and constitute less than 1% of all spinal tumors. Such tumors are usually associated with spinal dysraphism and occur mostly in the lumbosacral or cervical region. Intradural spinal lipomas tends to be intramedullary or subpial. Meningeal melanocytoma is further rarer cases that comprise less than 0.1% of cases. These usually occur in the fifth or fifth decade and chances of malignant transformation are high.

CASE REPORT

Here, we report an extremely rare case (first to the best of our knowledge) of a 9 years female child who presented to us with rapid progressing paraparesis. She was operated and found to have an intradural purely extramedullary spinal lipoma without spinal dysraphism. Moreover, she had melanin pigment deposits all over her meninges which is further rare. On presentation, the patient was bedridden but after surgery, the patient improved and could walk without support.

CONCLUSIONS

To the best of our knowledge, this is the first case of spinal cord lipoma in dorsal location along with melanin pigments in the meninges. We discuss the pathogenesis, presentation and management of intradural extramedullary spinal lipomas.

Incidence of neurocutaneous melanosis in Japanese pediatric patients with congenital melanocytic nevi

Neurocutaneous melanosis (NCM) is a rare, non-hereditary neurocutaneous disorder characterized by excessive melanocytic proliferation in the skin and central nervous system. As no major studies have covered the incidence of NCM among Japanese patients with congenital melanocytic nevi (CMN), we prospectively investigated the incidence of NCM among Japanese patients who underwent initial treatment for CMN. The relationship of CMN and NCM was also investigated. Japanese pediatric patients with CMN under 1 year of age were included between January 2020 and November 2022, and all patients underwent brain MRI to check for NCM in this study. NCM lesions were most frequently seen in the amygdala, followed by the cerebellum, brainstem, and cerebral hemispheres. NCM was diagnosed on brain MRI in 31.6% of the 38 patients with CMN and in 25.0% of patients with no prior examination or treatment. Distribution and size of CMN, number of satellite nevi, rugosity and nodules were strongly associated with the existence of NCM, and these findings may guide a future registry study with a large cohort of CMN patients.

SCALP syndrome with a germline heterozygous DOCK6 mutation and somatic mosaic NRAS Q61R mutation

We present a case of SCALP syndrome, which was diagnosed in a male infant with the characteristic findings of sebaceous nevi, central nervous system malformations, aplasia cutis congenita, limbal dermoid, and giant congenital melanocytic nevi, or pigmented nevi. We identified a germline compound heterozygous DOCK6 mutation and a somatic mosaic NRAS Q61R mutation in the giant congenital melanocytic nevus. This report will increase clinician awareness of SCALP syndrome and augment the literature in characterizing this rare syndrome, including its genetic background.

Serial excision surgery for giant dorsal congenital melanocytic nevus: Case report

INTRODUCTION AND IMPORTANCE

Giant congenital melanocytic nevus increases the risk of melanoma and seriously affects the aesthetics and psychology of patients, influencing the personality development of children.

CASE PRESENTATION

A 7-year-old female child presented with a giant congenital melanocytic nevus on the back, which extended from the right anterior abdominal wall to the left flank Taking advantage of the elasticity of children's skin, we performed serial excision and obtained favourable results. The procedure included seven surgeries, and the average interval between the surgeries was 7 months. The nevus was partially resected from the periphery to the centre, and the direction of excision of the nevus depended on the mobilisation of the surrounding normal skin, including from the shoulder downward, lateral to medial, and from the bottom upward. After the seventh surgery at 11 years of age, the nevus was completely removed, and there were no complications.

CLINICAL DISCUSSION

Serial excision is a simple and less invasive surgical technique that can achieve both complete excision and a satisfactory aesthetic result for giant congenital melanocytic nevus. The giant nevus of the back can be removed completely after several procedures due to the very good elasticity of the skin and the great ability of natural expansion of healthy skin under a considerable stretching force in children.

CONCLUSION

Serial excision is an effective method for treating dorsal giant congenital melanocytic nevus in children because of excellent natural skin elasticity.

Safety and effectiveness of surgical excision of medium, large, and giant congenital melanocytic nevi: A systematic review and meta-analysis

BACKGROUND

Treatment indications of congenital melanocytic naevi (CMN) have shifted from the prevention of malignant transformation more towards the improvement of appearance and psychosocial health. Surgical excision is often preferred, but its safety and effectiveness remain unclear.

OBJECTIVE

To assess the outcomes of surgical excision of medium-to-giant CMN.

PRIMARY OUTCOME

safety (complications).

SECONDARY OUTCOME

effectiveness (satisfaction and CMN core outcomes).

METHODS

PubMed, EMBASE, and CENTRAL were searched for studies on the excision of medium-to-giant CMN and/or CMN requiring reconstruction or serial excision. Meta-analyses of safety per patient were conducted, and pooled outcomes of safety and effectiveness were presented in summary-of-findings tables.

RESULTS

A total of 1444 studies were found, of which 22 were included, evaluating 643 eligible patients. Study quality varied, and reporting of baseline characteristics and outcomes was heterogeneous. Pooled proportions were overall 9.8% for major wound-related complications, 1.2% for minor wound-related complications, 1.2% for scar-related complications, and 4.3% for anatomical deformities. For large/giant CMN, complication rates were, respectively, 23.1%, 2.9%, 12.9%, and 2.4%; and for CMN with eyelid involvement, 0.5%, 3.3%, 0.4%, and 54.2%. Patients rated their satisfaction with the cosmetic outcome as 24.4% excellent, 71.0% good, and 4.6% poor/moderate. Physicians rated this as 18.3% excellent, 70.1% good, and 11.7% poor/moderate. Thirty-five other outcomes of effectiveness were summarized. However, many were rarely reported.

CONCLUSIONS

Surgical excision of CMN appears to be safe and effective in many cases, depending on CMN size and location. Major wound-related complications and scar-related complications occurred more frequently with large/giant CMN, whereas anatomical deformities occurred with the majority of CMN with eyelid involvement.

Measurement instruments for the core outcome set of congenital melanocytic naevi and an assessment of the measurement properties according to COSMIN: a systematic review

Background

Congenital melanocytic naevi (CMN) can impact on patients' lives due to their appearance and the risk they carry of neurological complications or melanoma development. The development of a core outcome set (COS) will allow standardised reporting and enable comparison of outcomes. This will help to improve guidelines. In previous research, relevant stakeholders reached a consensus over which core outcomes should be measured in any future care or research. The next step of the COS development is to select the appropriate measurement instruments.

Aim

Step 1: to update a systematic review identifying all core outcomes and measurement instruments available for CMN. Step 2: to evaluate the measurement properties of the instruments for the core outcomes.

Methods

This study was registered in PROSPERO and performed according to the PRISMA checklist. Step 1 includes a literature search in EMBASE (Ovid), PubMed and the Cochrane Library to identify core outcomes and instruments previously used in research of CMN. Step 2 yields a systematic search for studies on the measurement properties of instruments that were either developed or validated for CMN, including a methodological quality assessment following the COSMIN methodology.

Results

Step 1 included twenty-nine studies. Step 2 yielded two studies, investigating two quality of life measurement instruments.

Conclusion

Step 1 provided an overview of outcomes and instruments used for CMN. Step 2 showed that additional research on measurement properties is needed to evaluate which instruments can be used for the COS of CMN. This study informs the instrument selection and/or development of new instruments.

Neurological signs, symptoms and MRI abnormalities in patients with congenital melanocytic naevi and evaluation of routine MRI-screening: systematic review and meta-analysis

Background

A congenital melanocytic naevus (CMN) is a rare skin condition that can be associated with abnormalities of the central nervous system (CNS). These anomalies can sometimes cause severe complications, and rarely death. Adequate information about aetiology and management is therefore crucial. To identify how to monitor patients with CMN, we aimed to estimate the prevalence of neurological involvement in patients with CMN and to summarize what specific neurological signs and symptoms and MRI abnormalities are reported in the medical literature. In addition, we summarized and evaluated the recommendations regarding MRI-screening reported in the medical literature.

Methods

This review was registered in PROSPERO and reported according to the MOOSE checklist. A search was conducted in EMBASE (Ovid), PubMed, and the Cochrane Library. We included studies with 10 or more patients with CMN, reporting on neurological signs and symptoms or CNS MRI. Study selection, data extraction and methodological quality assessment were performed by two independent reviewers. A meta-analysis was used to assess the prevalence of neurological signs and symptoms.

Results

Out of 1287 studies, fourteen studies were eligible for inclusion of which eight were included in the meta-analysis. Neurological signs and symptoms prevalence was 7.04% (CI 95% 4.47–10.93%) in the meta-analysis group and 6.26% (95% CI 3.85–10%) in a subgroup of patients with a CMN > 6 cm, evaluated in seven studies. Neurodevelopmental delay and seizures were the most frequently reported signs and symptoms. CNS melanocytosis and hydrocephalus were the most frequently reported MRI abnormalities. It was not possible to estimate the increased risk of neurological involvement in patients with CMN due to low quality of evidence and clinical heterogeneity.

Conclusion

Standardization in CMN studies and a multi-centre prospective study are needed to evaluate neurological involvement. Based on current literature, it is not possible to make strong recommendations on routine MRI-screening. For now, every clinical centre should decide on its own policy and weigh the advantages and disadvantages of routine MRI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-022-02234-8.

Risk of Malignant Transformation Arising From Giant Congenital Melanocytic Nevi: A 20-year Single-center Study

BACKGROUND

Although giant congenital melanocytic nevus (GCMN) is regarded as premalignant, the incidence and risk factors of malignant transformation are controversial.

OBJECTIVE

This study aimed to share the authors' surgical experience with GCMNs and provide data on their demographics, malignant transformation, and prognosis.

METHODS

This single-center, consecutive study included 152 patients with GCMN who visited this center from March 2000 to February 2020. Their medical documentation was reviewed retrospectively, and the nevi were classified according to the size as follows: Group 1, 10 to 19.9 cm (n = 45); Group 2, 20 to 39.9 cm (n = 62); and Group 3, ≥40 cm (n = 45).

RESULTS

Seven malignancies were found (4.6%; 4 melanomas, 2 rhabdomyosarcomas [RMS], and 1 malignant peripheral nerve sheath tumor [MPNST]). The risk increased according to the nevus size (2.2% in Group 1, 3.2% in Group 2, and 8.9% in Group 3) but the difference was not statistically significant (p = .3305).

CONCLUSION

Malignant transformation from GCMN cannot be ignored. It can include transformation into melanoma, RMS, and MPNST. Early surgical resection and regular follow-up should be performed in patients with nevi ≥10 cm.

Surgical outcomes and psychosocial impact of giant congenital melanocytic nevus surgery: A single-center case series of 136 patients

PURPOSE

The aim of this study was to evaluate the outcomes, complications and psychosocial impact of surgical treatment of giant congenital melanocytic nevus (GCMN).

METHODS

Patients with surgically treated GCMN who attended our clinic between May 2014 and May 2018 were included. Patient demographics and data on the characteristics of the nevus, surgical treatment, and the psychosocial impact (including C-DLQI/DLQI questionnaires) were collected.

RESULTS

One hundred thirty-six patients were included (median age 9 years). Mean age at first surgery was 34 (+/- 61.45) months; 5.53 (+/- 3.69) surgical interventions were necessary to completely excise the nevus. The expanded skin flap was the preferred surgical technique in most locations. Complications were common but not severe. Of the patients studied, 70.4% reported that the surgery had a minor impact on their quality of life (QoL). Patients and caregivers stated that surgical treatment should begin as soon as possible, even in cases where early treatment did not have an impact on their QoL nor on their satisfaction with the surgery (p < 0.05). The lower the patient age at first surgery, the higher the surgeon's satisfaction (p < 0.01).

CONCLUSIONS

Surgical treatment is a safe option for management of GCMN, and has a low impact on QoL. Patients, caregivers, and surgeons agree that the treatment should begin as soon as possible. This is the largest single-center study evaluating surgical treatment in GCMN patients and its psychosocial impact, and the first to take into account the patient, caregivers and dermatologists opinion of surgical results.

Current concepts of ectopic nodal inclusions with special emphasis on nodal nevi

Nodal inclusions of ectopic tissue within lymph nodes are seen comparatively often in dermatopathology and general pathology. Glandular and nonglandular epithelium, as well as melanocytic nevi can be observed within lymph nodes and represent mostly incidental findings without any relevance. The main challenge in reporting these morphologic features is to differentiate such benign inclusions from metastatic settlements of distinct organ tumors. As sentinel node biopsy and lymph node dissection have become standard procedure in clinical oncology and have an immense clinical impact, the correct evaluation of these nodal inclusions is indispensable to avoid undertreatment or overtreatment of patients. In addition, the genesis of these inclusions has not yet been satisfactorily clarified. Two concepts have been laid out: the theory of benign metastases and the migration arrest theory. However, neither theory has so far been able to answer the following questions: Why do we find more nodal nevi in patients with melanoma who had a sentinel node biopsy than in patients without melanoma, and why do we not find nodal nevi in deep visceral lymph nodes? We present a comprehensive review of the current knowledge on nodal inclusions, proposing a concept for the pathogenesis of nodal nevi, to answer these questions.

Imaging and clinical features of neurocutaneous melanosis in the pediatric population

BACKGROUND

Neurocutaneous melanosis (NCM) is a rare nonfamilial phakomatosis characterized by the presence of congenital melanocytic nevi and abnormal melanocytes infiltration of the leptomeninges.

OBJECTIVE & METHODS

This paper shows the importance of early diagnosis and the most important imaging features of the disease on CT and MR scans. PubMed database was searched from January 1972 to September 2020. Papers including imaging findings of NCM, clinical, follow-up, and treatment features were collected, selecting only 89 studies.

DISCUSSION

NCM is a term used for the first time by van Bogaert in 1948. It refers to a condition caused by an error during morphogenesis and migration leading to leptomeningeal melanocytic accumulation. Although histological findings are the gold standard for diagnosis confirmation, neuroimaging and clinical features strongly support the suspect of NCM. Localization and extension of the lesions are predictive of neurological manifestations related to increased intracranial pressure, mass lesions, or spinal cord compression. CT demonstrates sites of increased density in the anterior temporal lobe - mainly the amygdala - thalami, cerebellum, and frontal lobes base. However, MRI is the best imaging method to diagnose central nervous system lesions, often appearing as T1-short signal areas of the cerebral parenchyma, indicative of central nervous system melanosis. MRI can also reveal associated intracranial and intraspinal abnormalities.

CONCLUSION

Early imaging, when available, is helpful if NCM suspect is raised and may be of guidance in comparing later studies. NCM requires a multidisciplinary approach since it is a multisystem disease with a genetic component.

Domains and outcomes of the core outcome set of congenital melanocytic naevi for clinical practice and research (the OCOMEN project): part 2

Background

Congenital melanocytic naevi (CMN) can have a great impact on patients’ lives owing to perceived stigmatization, and the risk of melanoma development and neurological complications. Development of a core outcome set (COS) for care and research in CMN will allow standard reporting of outcomes. This will enable comparison of outcomes, allowing professionals to offer advice about the best management options. In previous research, stakeholders (patients, parents and professionals) reached consensus on the core domains of the COS. To select the appropriate measurement instruments, the domains should be specified by outcomes.

Objectives

To reach consensus on the specific core outcomes describing the core domains pertaining to clinical care and research in CMN.

Methods

A list of provisional outcomes (obtained earlier) was critically reviewed by the Outcomes for COngenital MElanocytic Naevi (OCOMEN) research team and by relevant stakeholders through an online questionnaire, to refine this list and provide clear definitions for every outcome. When needed, discussion with individual participants was undertaken over the telephone or by email. During an online consensus meeting, stakeholders discussed the inclusion of potential outcomes. After the meeting, participants voted in two rounds for the inclusion of outcomes.

Results

Forty‐four stakeholders from 19 countries participated. Nine core outcomes were included in the COS relative to clinical care and 10 core outcomes for research.

Conclusions

These core outcomes will enable standard reporting in future care and research of CMN. This study facilitates the next step of COS development: selecting the appropriate measurement instruments for every outcome.

What is already known about this topic?

Congenital melanocytic naevi (CMN) can be associated with psychosocial burden and increased risk of melanoma and/or neurological complications.

Outcomes measured for research and care in CMN are heterogeneous, impeding comparison.

A core outcome set (COS) may enhance standardized use and reporting, and reduce selective reporting bias.

In previous research, relevant stakeholders reached consensus on what domains should be included in the core domain set (CDS).

What does this study add?

To select the appropriate measurement instruments for the domains included in the CDS, the domains should be further specified by outcomes.

We reached consensus on what outcomes should describe the domains of the CDS of CMN care and research.

Through a consensus procedure, including online discussions, online consensus meeting and voting, relevant stakeholders reached consensus on a limited number of core outcomes describing the core domains.

What are the clinical implications of this work?

Development of a COS will allow standard reporting of outcomes in future care and research of CMN.

This will enable pooling and comparison of outcomes, allowing guideline development of optimal management policy.

Linked Comment: M.V. Heppt et al. Br J Dermatol 2021; 185:881–882.

Plain language summary available online

Cerebellar amelanotic melanoma can mimic cerebellar abscess in a pediatric case of neurocutaneous melanosis

Neurocutaneous melanosis (NCM) is a rare phakomatosis that may be associated with intracerebral masses. The differential diagnosis of intracerebral masses in NCM is often challenging and should include pigmented and nonpigmented lesions.

Cholesterol was identified as a biomarker in human melanocytic nevi using DESI and DESI/PI mass spectrometry imaging

The rapid differentiation between diseased tissue and healthy normal tissue is of great importance for the intraoperative diagnosis. Herein, desorption electrospray ionization (DESI) and DESI/post-photoionization (DESI/PI) mass spectrometry imaging were combined to in situ visualize the distribution of biochemicals within the tissue regions of human melanocytic nevi under the ambient condition with a spatial resolution of around 200 μm. Plenty of polar and nonpolar lipids were found to be specifically distributed in melanocytic nevi with statistical significance and could be used to differentiate the healthy normal tissue and melanocytic nevi. Cholesterol was further confirmed to be a potential biomarker for melanocytic nevi diagnosis by multivariate statistical analysis and immunohistochemistry of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) and translocator protein (TSPO) enzymes. This work provides a visual way for the diagnosis of human melanocytic nevi by lipid profiling, which benefits the understanding of the pathological mechanism of melanocytic nevi and provides a new insight to control melanin growth from the synthesis, transport, and metabolism of cholesterol.

Neurocutaneous Melanocytosis and Leptomeningeal Melanoma

Neurocutaneous melanocytosis (NCM) is a disorder characterized by multiple or large congenital nevi and excessive proliferation of melanocytes in the leptomeninges and brain parenchyma. The majority of NCM is a result of somatic mosaicism due to a single postzygotic mutation in codon 61 of NRAS. Patients with NCM are at high risk of developing leptomeningeal melanoma. The prognosis for leptomeningeal melanoma is poor with no known effective treatment options. We describe the clinical features, treatment, and outcome of 4 children with NCM and leptomeningeal melanoma and discuss the latest molecular findings and treatment options for this rare condition.

Development of an international core domain set for medium, large and giant congenital melanocytic naevi as a first step towards a core outcome set for clinical practice and research

BACKGROUND

Medium, large and giant congenital melanocytic naevi (CMN) can impose a psychosocial burden on patients and families, and are associated with increased risk of developing melanoma or neurological symptoms. Lack of consensus on what outcomes to measure makes it difficult to advise patients and families about treatment and to set up best practice for CMN.

OBJECTIVES

Fostering consensus among patient representatives and professionals, we aim to develop a core outcome set, defined as the minimum set of outcomes to measure and report in care and all clinical trials of a specific health condition. We focused on the 'what to measure' aspect, the so-called core domain set (CDS), following the COMET and CS-COUSIN guidelines.

METHODS

We conducted a systematic review to identify outcomes reported in the literature. Focus groups with patient representatives identified patient-reported outcomes. All these outcomes were classified into domains. Through e-Delphi surveys, 144 stakeholders from 27 countries iteratively rated the importance of domains and outcomes. An online consensus meeting attended by seven patient representatives and seven professionals finalized the CDS.

RESULTS

We reached consensus on six domains, four of which were applied to both care and research: 'quality of life', 'neoplasms', 'nervous system' and 'anatomy of skin'. 'Adverse events' was specific to care and 'pathology' to research.

CONCLUSIONS

We have developed a CDS for medium-to-giant CMN. Its application in reporting care and research of CMN will facilitate treatment comparisons. The next step will be to reach consensus on the specific outcomes for each of the domains and what instruments should be used to measure these domains and outcomes.

Congenital melanocytic naevi: An up-to-date overview

Congenital melanocytic naevi are hamartomas of the neuroectoderm caused by genetic mosaicism. Congenital melanocytic naevi are seen in 1-6% of all live births and commonly classified based on the projected size in adults. Congenital melanocytic naevi appear in different colours, shapes, and sizes, and occasionally present with complications. In this review, we sought to evaluate congenital melanocytic naevi, their clinical, dermatoscopic, and reflectance confocal microscopic features, behavioural pattern over time, new trends in classification, underlying genetic factors and their influence on clinical manifestations and management, associated risks, complications, magnetic resonance imaging findings and their management in the light of recent literature.

Spastic quadriplegia following intradermal use of hydrogen peroxide in the tardive curettage procedure for the treatment of a giant congenital nevus

The possible transformation of a giant congenital melanocytic nevi (GCMN) in malignant melanoma estimated from 0.05% to 40% depend on the size of the lesions. Many are the surgical procedures proposed, including: full or partial-thickness excisions, dermabrasion, curettage in the first weeks of life and laser treatment. The curettage technique has been proposed in the literature for the treatment of GCMN in the first few weeks of life and defined as a relatively atraumatic surgery procedure without general complications. The authors report the first case in the literature of embolization due to use of subcutaneous peroxide infiltration before a tardive curettage procedure in a newborn case of GCMN resulting in spastic quadriplegia with dystonic reaction. Consequently, a lawsuit, due to this medical malpractice, has been opened.

Clinical Follow-Up of Patients with Neurocutaneous Melanosis in a Tertiary Center; Proposed Modification in Diagnostic Criteria

INTRODUCTION

Neurocutaneous melanosis (NCM) is a rare congenital syndrome. Except for some retrospective studies, information on clinical follow-up and management of these patients are limited. This study aimed to review our experience on diagnostic protocol and clinical follow-up of patients with NCM in a referral children's hospital in Iran.

METHODS

Between 2012 and 2019, eight patients with NCM were consecutively managed in our center. Brain magnetic resonance imaging and cutaneous biopsy were done in all patients at diagnosis. Follow-up surveillance and characteristics of the disease are described.

RESULTS

The mean follow-up period was 25.75 ± 13.81 months, and 75% of patients were male. Most magnetic resonance imaging findings were hypersignal lesions in the temporal lobe (75%), cerebellum (62.5%), brainstem (50%), and thalamus (12.5%). Dandy-Walker syndrome was found in 4 patients (50%), and shunt-dependent hydrocephalus was found in 3 patients (37.5%). Cutaneous malignant melanoma and malignant involvement of the central nervous system were found in 2 (25%) and 3 cases (37.5%), respectively. The mortality rate was 37.5%.

CONCLUSIONS

There are no specific guidelines for management of NCM due to the rarity of the disease. This study proposed modifications in diagnostic criteria, as well as recommendations for follow-up surveillance.

Neurocutaneous melanocytosis (melanosis)

Neurocutaneous melanosis (NCM; MIM # 249400; ORPHA: 2481], first reported by the Bohemian pathologist Rokitansky in 1861, and now more precisely defined as neurocutaneous melanocytosis, is a rare, congenital syndrome characterised by the association of (1) congenital melanocytic nevi (CMN) of the skin with overlying hypertrichosis, presenting as (a) large (LCMN) or giant and/or multiple (MCMN) melanocytic lesions (or both; sometimes associated with smaller "satellite" nevi) or (b) as proliferative melanocytic nodules; and (2) melanocytosis (with infiltration) of the brain parenchyma and/or leptomeninges. CMN of the skin and leptomeningeal/nervous system infiltration are usually benign, more rarely may progress to melanoma or non-malignant melanosis of the brain. Approximately 12% of individuals with LCMN will develop NCM: wide extension and/or dorsal axial distribution of LCMN increases the risk of NCM. The CMN are recognised at birth and are distributed over the skin according to 6 or more patterns (6B patterns) in line with the archetypical patterns of distribution of mosaic skin disorders. Neurological manifestations can appear acutely in infancy, or more frequently later in childhood or adult life, and include signs/symptoms of intracranial hypertension, seizures/epilepsy, cranial nerve palsies, motor/sensory deficits, cognitive/behavioural abnormalities, sleep cycle anomalies, and eventually neurological deterioration. NMC patients may be symptomatic or asymptomatic, with or without evidence of the typical nervous system changes at MRI. Associated brain and spinal cord malformations include the Dandy-Walker malformation (DWM) complex, hemimegalencephaly, cortical dysplasia, arachnoid cysts, Chiari I and II malformations, syringomyelia, meningoceles, occult spinal dysraphism, and CNS lipoma/lipomatosis. There is no systemic involvement, or only rarely. Pathogenically, single postzygotic mutations in the NRAS (neuroblastoma RAS viral oncogene homologue; MIM # 164790; at 1p13.2) proto-oncogene explain the occurrence of single/multiple CMNs and melanocytic and non-melanocytic nervous system lesions in NCM: these disrupt the RAS/ERK/mTOR/PI3K/akt pathways. Diagnostic/surveillance work-ups require physical examination, ophthalmoscopy, brain/spinal cord magnetic resonance imaging (MRI) and angiography (MRA), positron emission tomography (PET), and video-EEG and IQ testing. Treatment strategies include laser therapy, chemical peeling, dermabrasion, and surgical removal/grafting for CMNs and shunt surgery and surgical removal/chemo/radiotherapy for CNS lesions. Biologically targeted therapies tailored (a) BRAF/MEK in NCM mice (MEK162) and GCMN (trametinib); (b) PI3K/mTOR (omipalisib/GSK2126458) in NMC cells; (c) RAS/MEK (vemurafenib and trametinib) in LCMNs cells; or created experimental NMC cells (YP-MEL).

Proliferative nodule resembling angiomatoid Spitz tumor with degenerative atypia arising within a giant congenital nevus

Proliferative nodules arising within congenital melanocytic nevi often present a diagnostic challenge given a close resemblance to melanoma. Several morphologic variants have been characterized. In difficult cases, ancillary molecular tests can be used to better exclude the possibility of malignant degeneration. Herein, we report a case of an unusual proliferative nodule with overlapping features of angiomatoid Spitz tumor and ancient melanocytic nevus, which demonstrated normal findings on both chromosomal microarray and a gene expression profiling assay.

A Unique Case of Lower Limb Soft Tissue Reconstruction with a Prefabricated Bipedicled Deep Inferior Epigastric Artery Flap

Aesthetic lower-extremity reconstruction is a secondary field in lower limb reconstructive surgery. Nevertheless, it plays an important role in the final stages of patient rehabilitation after traumatic events, treatment of deformations, and oncoplastic surgery, and in unique cases of purely aesthetic reconstruction. We present a clinical case of lower limb reconstruction with a prefabricated bipedicled deep inferior epigastric artery (DIEP) flap in a young patient who underwent a massive congenital circular pigmented nevus excision surgery. Due to the lack of sufficient donor site tissues anywhere on the body, a bilateral DIEP flap was prefabricated using tissue expansion. Two expanders were used to prepare the donor site. Six months after expansion, lower limb reconstruction was performed. A large (50 × 25cm2) surgical defect was covered by a prefabricated DIEP flap. Flap positioning was regarded with extra care due to importance of proper venous outflow in accordance with lower limb venous anatomy. Treatment results were above the satisfactory level both aesthetically and therapeutically. Aesthetic and therapeutic incentives were assessed before surgical treatment decision. Large defects of the lower limbs require significant amount of excess tissue in the donor site and may require prefabrication. In young patients with low BMI, flap transfer is nearly impossible without prior expansion. In this case, we successfully performed giant pigmented nevus excision, with immediate reconstruction with a prefabricated bilateral DIEP flap. Venous outflow was problematic due to the anatomical structure of lower limb veins. This required extra venous drainage and special regard to positioning of the flap.

Management of Congenital Melanocytic Nevus on Face Using Multiple Re-expansion Method: Aesthetic and Psychosocial Results

BACKGROUND

Congenital giant melanocytic nevus on the face is a challenging condition, especially in the pediatric population. It can produce significant cosmetic deformity with negative psychosocial effects in pediatric patients even after treatment. The objective of this study was to report aesthetic and psychosocial results in the management of congenital melanocytic nevus on the face using multiple reexpansion.

METHODS

Data of 6 patients with congenital melanocytic nevus on the face who underwent excision and multiple reexpansion at our center from September 2004 to August 2017, were retrospectively reviewed. To evaluate aesthetic outcomes, preoperative and final photographs of each patient were reviewed by 3 other plastic surgeons and 4 laypersons. For comparison, 6 other patients who were treated with conventional surgery during the same period were reviewed. After final reconstruction surgery, the authors surveyed patients' satisfaction via telephone.

RESULTS

Six patients were followed up for an average of 87.66 months (range, 55-123 months). The mean number of tissue expander insertions was 3.33 and the mean number of total expanders inserted was 4.83. Complication associated with expander exposure occurred in 1 patient during the fifth expansion. The average score of aesthetic outcome in the multiple reexpansion group was superior to that of the conventional group (2.60 versus 2.10, P = 0.03). During the telephone survey, patients did not rate their appearance as positive, although they were comparatively satisfied with the surgical procedure.

CONCLUSION

Considering the low rate of malignancy involving congenital melanocytic nevus in childhood, multiple reexpansion is an attractive option to obtain better results compared with other reconstructive methods.

Imaging of pediatric cutaneous melanoma

Melanoma accounts for 7% of all cancers in adolescents ages 15-19 years but is an unexpected malignancy in younger children. The prevalence of malignant melanoma is very rare in children ages 1-4 years, but certain non-modifiable risk factors such as xeroderma pigmentosum, congenital melanocytic nevus syndrome and other inherited traits increase the risk for its development in these young children. Recent genomic studies have identified characteristics of pediatric melanoma that differ from conventional melanoma seen in adults. In this review the authors inform on the types of melanoma seen in children and adolescents, discuss similarities and differences in melanoma between children and adults, and discuss the role of imaging in the care of these children.

Melanoma arising in a Giant congenital melanocytic nevus: two case reports

Background

A giant congenital melanocytic nevus (GCMN) is found in 0.1% of live-born infants. If present, the lesion has a chance of about 6% to develop into malignant melanoma. Both children and adults can be affected by malignant melanoma arising in a giant congenital nevus. Up to 95% of GCMNs harbor NRAS mutations, and mutations in the BRAF, MC1R, TP53, and GNAQ genes have also been described. The individualization of therapy is required, but diagnostic and prognostic criteria remain controversial.

Case presentations

We report two cases: 1) melanoma arising in a giant congenital nevus during the first month of life complicated with neurocutaneous melanosis (NCM), and 2) melanoma arising in a giant congenital nevus during the first 6 months of life. Pathology, immunohistochemistry, and genetic analyses of tumor tissue were performed. The first case revealed only a non-pathogenic P72R polymorphism of the TP53 gene in the homozygote condition. For the second case, a Q61K mutation was detected in the NRAS gene.

Conclusion

Malignant melanoma associated with GCMN is rare and therefore poorly understood. Outcomes have been linked to the stage at diagnosis, but no additional pathological prognostic factors have been identified. The most frequent genetic event in giant CMNs is NRAS mutations, which was discovered in one of our cases. To accumulate evidence to improve disease prognosis and outcomes, children with congenital melanocytic nevus should be included in a systemic follow-up study from birth.

Melanoma in children, adolescents and young adults: anatomo-clinical features and prognostic study on 426 cases

PURPOSE

This study was conducted to determine the difference in anatomo-pathological and prognostic features of cutaneous melanoma in children, adolescents and young adults.

METHODS

This is a retrospective review on 383 young patients ≤ 39 years of age with cutaneous melanoma, in a period from 2006 to 2016 in Area Vasta Nord Ovest, Tuscany, Italy. We subdivided patients in three groups (children ≤ 14 years, adolescents 15-21 years, young adults 22-39 years). We correlated all the anatomo-pathological parameters with age groups.

RESULTS

We identified a total of 426 cases of cutaneous melanoma on an overall total of 383 patients. Mean age at diagnosis for all the patients ≤ 39 years of age was 31.2 years: in group A was 11.2 years, in group B 19.2 years and in group C 32.5 years. Incidence, in the subjects between 0 and 14 years, is 14 cases per million inhabitants, between 15 and 21 years of 145, and between 22 and 39 years of 394. Global incidence was 1.6 case per million for group A, 8.9 cases per million for group B, 105 cases per million for group C. No statistically significative correlation could be described for clinical parameters and age groups.

CONCLUSIONS

Incidence of melanoma in our casuistry results as the highest in the world. These data open new study for this kind of cancer.

A Practical Approach to the Diagnosis of Melanocytic Lesions

CONTEXT.—

Melanocytic lesions are common in routine surgical pathology. Although the majority of these lesions can be confidently diagnosed using well-established morphologic criteria, there is a significant subset of lesions that can be diagnostically difficult. These can be a source of anxiety for patients, clinicians, and pathologists, and the potential consequences of a missed diagnosis of melanoma are serious.

OBJECTIVE.—

To provide a practical approach to the diagnosis of melanocytic lesions, including classic problem areas as well as suggestions for common challenges and appropriate incorporation of ancillary molecular techniques.

DATA SOURCES.—

Literature search using PubMed and Google Scholar, incorporating numerous search terms relevant to the particular section, combined with contemporaneous texts and lessons from personal experience.

CONCLUSIONS.—

Although a subset of melanocytic lesions can be diagnostically challenging, the combination of a methodical approach to histologic assessment, knowledge of potential diagnostic pitfalls, opinions from trusted colleagues, and judicious use of ancillary techniques can help the pathologist navigate this difficult area.

Tissue Engineered Skin Substitutes

The fundamental skin role is to supply a supportive barrier to protect body against harmful agents and injuries. Three layers of skin including epidermis, dermis and hypodermis form a sophisticated tissue composed of extracellular matrix (ECM) mainly made of collagens and glycosaminoglycans (GAGs) as a scaffold, different cell types such as keratinocytes, fibroblasts and functional cells embedded in the ECM. When the skin is injured, depends on its severity, the majority of mentioned components are recruited to wound regeneration. Additionally, different growth factors like fibroblast growth factor (FGF), epidermal growth factor (EGF), vascular endothelial growth factor (VEGF) are needed to orchestrated wound healing process. In case of large surface area wounds, natural wound repair seems inefficient. Inspired by nature, scientists in tissue engineering field attempt to engineered constructs mimicking natural healing process to promote skin restoration in untreatable injuries. There are three main types of commercially available engineered skin substitutes including epidermal, dermal, and dermoepidermal. Each of them could be composed of scaffold, desired cell types or growth factors. These substitutes could have autologous, allogeneic, or xenogeneic origin. Moreover, they may be cellular or acellular. They are used to accelerate wound healing and recover normal skin functions with pain relief. Although there are a wide variety of commercially available skin substitutes, almost none of them considered as an ideal equivalents required for proper wound healing.

Melanoma in congenital melanocytic naevi

Congenital melanocytic naevi (CMN) are a known risk factor for melanoma, with the greatest risk currently thought to be in childhood. There has been controversy over the years about the incidence of melanoma, and therefore over the clinical management of CMN, due partly to the difficulties of histological diagnosis and partly to publishing bias towards cases of malignancy. Large cohort studies have demonstrated that melanoma risk in childhood is related to the severity of the congenital phenotype. New understanding of the genetics of CMN offers the possibility of improvement in diagnosis of melanoma, identification of those at highest risk, and new treatment options. We review the world literature and our centre's experience over the last 25 years, including the molecular characteristics of melanoma in these patients and new melanoma incidence and outcome data from our prospective cohort. Management strategies are proposed for presentation of suspected melanoma of the skin and the central nervous system in patients with CMN, including use of oral mitogen-activated protein kinase kinase inhibitors in NRAS-mutated tumours.

Congenital melanocytic nevi in young children: Histopathologic features and clinical outcomes

BACKGROUND

Although only large congenital melanocytic nevi (CMN) are associated with a significantly high risk for malignant transformation, CMN of all sizes are prone to changes in clinical appearance in early childhood and thus are often biopsied or excised. While CMNs typically exhibit benign behavior, atypical histopathologic findings might be common and may prompt additional unnecessary procedures.

OBJECTIVE

To assess the prevalence and associated clinical outcomes of atypical histopathologic features in CMN in children.

METHODS

A single center retrospective study was conducted with patients 0-35 months of age with CMN diagnosed by histopathology between 1993-2013.

RESULTS

One hundred seventy-nine patients with a total of 197 CMNs were identified. Cytologic atypia, architectural disorder, or pagetoid spread were present in 73% of CMN. With a mean follow up of 7.3 years, no cases of melanoma or CMN-related deaths were identified.

LIMITATIONS

Our findings were based on a largely Caucasian population and might not apply to darker skin types. Our findings might not apply to older children or adults with CMN.

CONCLUSION

Atypical histopathologic features of cytologic atypia, architectural disorder, and pagetoid spread are common in benign CMN of young children.

Tissue expansion in the treatment of giant congenital melanocytic nevi of the upper extremity

The aim of our study was to use tissue expansion for the treatment of giant congenital melanocytic nevi of the upper extremity and examine potential advantages over traditional techniques.There were 3 stages in the treatment of giant congenital melanocytic nevi of the upper extremities using tissue expansion: first, the expander was inserted into the subcutaneous pocket; second, the expander was removed, lesions were excised, and the wound of the upper extremity was placed into the pocket to delay healing; third, the residual lesion was excised and the pedicle was removed. The pedicle flap was then unfolded to resurface the wound.During the period between June 2007 and December 2015, there were 11 patients with giant congenital melanocytic nevi of the upper extremities who underwent reconstruction at our department with skin expansion. Few complications were noted in each stage of treatment. The functional and aesthetic results were observed and discussed in this study.Optimal aesthetic and functional results were obtained using tissue expansion to reconstruct the upper extremities due to the giant congenital melanocytic nevi.

A prospective study of patients with large congenital melanocytic nevi and the risk of melanoma

BACKGROUND:

Large congenital melanocytic nevus (LCMN) is considered a risk factor for melanoma, although the magnitude of this risk is controversial.

OBJECTIVE:

To evaluate the risk of melanoma development in patients with LCMN seen at a dermatology referral center in Brazil during a twelve-year period. To the best of our knowledge, there are no published similar studies on large congenital melanocytic nevus in South America.

METHODS:

Our prospective cohort included only patients with congenital nevi ≥20cm. The cumulative risk of developing melanoma and the standardized morbidity ratio were calculated for patients followed up prospectively for at least 1 month.

RESULTS:

Sixty-three patients were enrolled in this study. One patient who developed melanoma prior to enrollment was excluded, and five were eliminated because of insufficient follow-up time. Mean follow-up for the remaining 57 patients was 5.5 years (median 5.2 years). Median age of entry into the study was 2.6 years. Most patients (75.4%) underwent only clinical observation. Melanomas occurred in 2 (3.5%) patients. Five-year cumulative risk for melanoma was 4.8% (95% CI: 1.9-11.5%). Standardized morbidity ratio was 1584 (95% CI: 266-5232, p<0.001).

STUDY LIMITATIONS:

The small sample size reduces the accuracy of risk estimates.

CONCLUSIONS:

This study analyzed prospectively for the first time data from South America demonstrating that patients with LCMN have a higher risk of developing melanoma than the general population (p<0.001).

[Skin tumors in children]

The presence of a congenital or acquired cutaneous lesion is a frequent reason for consultation in pediatric plastic surgery unit. The management of these lesions requires a good knowledge of specific diagnoses in children. This step is sometimes difficult because of the multiplicity of possible diagnosis. Some skin tumors may be the external sign of a general disease or an underlying malformation; those can change the overall prognosis and management and require to be properly identified. The decision of surgical excision depends on various criteria, including diagnosis but also the reconstruction possibilities. The timing of surgical treatment depends on the medical emergency of the tumor resection (benign tumor, spontaneously regressive tumor, risk of degeneration into malignancy), on the cosmetic and psychological impact but also on the growth or learning steps in child life. This article first provides an aid in the diagnosis of the most common or more characteristic skin tumors. The algorithm is principally based on the pigmentation aspect of the tumor. The age and conditions of the surgical management are specified for each type of tumor. Cutaneous hemangiomas and vascular malformations, and congenital cysts and fistulas are not reported in this article.

Common Pediatric Skin Lesions: A Comprehensive Review of the Current Literature

The timely diagnosis and treatment of dermatologic disease in the pediatric population can be challenging. A basic, yet comprehensive knowledge of common lesions is essential for a successful practice in plastic surgery. In this article, the authors describe vascular, cystic, and pigmented cutaneous lesions that are commonly encountered in the pediatric population. Epidemiology, pathogenesis, clinical course, and management options are discussed for each.

Early diagnosis of asymptomatic neurocutaneous melanosis (60 month follow-up)

Neurocutaneous melanosis (NCM) is a rare, sporadic, congenital neuroectodermal dysplasia. Large congenital melanocytic nevi (CMN) can evolve in a certain percentage of patients to NCM. Meningeal deposits are benign, but can be prone to malignant transformation in some cases. We describe the case of an infant with asymptomatic NCM, and typical magnetic resonance imaging (MRI) findings. The diagnosis was established shortly after delivery, and the patient was followed for 60 months. At that time, the girl did not have any neurologic symptoms; she reached normal developmental milestones and did not show mental retardation and did not develop malignant melanoma; further follow-up will be needed, although there are no reliable guidelines as to the time range of follow up of asymptomatic NCM in the literature. We report the typical MRI signal abnormalities of the brain, and present a review of the literature regarding this rare and mysterious congenital disorder.