The shifting paradigm in the management of giant congenital melanocytic nevi: review and clinical applications

Facial Soft Tissue Lesions in Children

Facial soft tissue lesions in children are often classified based on their structure or cellular origin and can be benign or malignant. This review focuses on common facial soft tissue lesions in children, their clinical morphology, natural history, and medical and surgical management, with an emphasis on those considerations unique to soft tissue lesions present at this anatomic site.

Prevalence, incidence density and standardized morbidity rate of melanoma among patients with congenital melanocytic naevi: a systematic review

BACKGROUND

Congenital melanocytic naevi (CMN) are the result of aberrations in the mitogen-activated protein kinase signal transduction pathway. The risk of melanoma is the most important concern among patients with CMN because of its poor prognosis. However, as a result of the great variability between studies, the reported risk of melanoma varies considerably, making it difficult to provide reliable information.

OBJECTIVES

To evaluate the prevalence, incidence density and standardized morbidity ratio (SMR) of melanoma among patients with CMN.

METHODS

We conducted a systematic literature search of studies providing data on the risk of melanoma in patients with CMN following our registered and published protocol (PROSPERO: CRD42022383009).

RESULTS

Overall, 27 studies with a total of 11 480 patients with CMN and 82 patients developing melanoma were included for analysis. The prevalence of melanoma was 1.84% [95% confidence interval (CI) 1.13-2.99] in patients with CMN and 2.73% (95% CI 1.67-4.43) in the subgroup of patients with large CMN (LCMN). The incidence of melanoma was 237.56 (95% CI 97.79-575.96) per 100 000 person-years in patients with CMN and 585.73 (95% CI 315.39-1085.29) per 100 000 person-years in the LCMN subgroup. The SMR of melanoma was 122.27 (95% CI 11.84-1262.88) among all patients with CMN and 285.97 (95% CI 50.65-1614.59) in the subgroup of patients with LCMN.

CONCLUSIONS

Our research suggests that the risk of melanoma in the CMN population seems to have been overestimated in previous studies, but it is still significantly higher than that in the general population. In addition to the risk of melanoma, aesthetic improvement and mental health should also be taken into account when making management decisions.

Treatment of congenital melanocytic naevi of nose using multiple flaps in single stage in a paediatric patient and literature review

A girl in her middle childhood presented to the outpatient department (OPD) with a congenital melanocytic naevi (CMN) of the right nasal alar lobule. Her parents had aesthetic concerns and expressed their desire to get the lesion removed. The full-thickness excision of CMN was performed with the reconstruction of the defect using the nasolabial and dorsal nasal advancement flap with conchal cartilage to shape the contour of the ala.

Erbium: YAG laser treatment efficacy and association with histologic features for giant congenital melanocytic nevi management

BACKGROUND

Limited research exists on laser treatment of giant congenital melanocytic nevus (GCMN).

OBJECTIVE

We sought to elucidate the efficacy of the Erbium: YAG laser on GCMN and the histologic factors associated with a positive clinical response.

METHODS AND MATERIALS

Between 2019 and 2022, we enrolled 30 medium-to-giant CMN patients who underwent Er: YAG laser treatment. All patients received biopsies before and after laser treatments. Clinical efficacy outcomes were evaluated by the investigator's global assessment (IGA), 5-point scale of depigmentation, and Vancouver Scar Scale (VSS) scores at least 6 months after treatment.

RESULTS

Of the 30 cases, 18 (60.0%) showed improvement (IGA score ≥3). Eight (26.7%) patients showed repigmentation. Eight (26.7%) patients developed hypertrophic scars. The average IGA, depigmentation, and VSS scores were 2.93, 3.57, and 3.20. The IGA score was higher (3.24 ± 1.18 vs. 2.22 ± 0.97, p = 0.031) and a lower repigmentation rate (14.3% vs. 55.6%, p = 0.032) was observed in the cases with Grenz zone. The IGA score was higher (3.33 ± 1.24 vs. 2.13 ± 0.89, p = 0.023) and the repigmentation rate was lower (11.1% vs. 50.0%, p = 0.034) also in the cases with the melanocytes nests with aggregation of melanin. Lesions with superficial ablation resulted in less hypertrophic scar formation than those with deep ablation (5.9% vs. 53.8%, p < 0.05).

CONCLUSION

The Er: YAG laser demonstrated effective clinical results for GCMNs. The grenz zone and the melanocytes nests with aggregation of melanin are promising predictors of laser efficacy.

Thickness of melanocytes in giant congenital melanocytic nevus for complete surgical excision: clinicopathological evaluation of 117 lesions according to the area and size

BACKGROUND

Giant congenital melanocytic nevi (GCMN) are usually defined as nevi that exceed 20 cm in maximal diameter or 15% of the total body surface area. There have been reports of life-long malignant change risks arising from GCMN, leading to surgical excision of GCMN. This study aims to evaluate the thickness of melanocytes based on clinical factors in order to provide objective information for the complete resection of the lesion.

METHODS

Overall, 75 patients diagnosed with GCMN between 2000 and 2021 were included, and their clinical records were collected retrospectively. 117 pathologic slides obtained during excision were reviewed to measure nevus thickness. Clinical factors were assessed with a generalized estimated equation model for association with nevus thickness.

RESULTS

The thickness of nevus was significantly associated with the location and size. Nevus thickness was more superficial in the distal extremity than in the head and trunk (P = 0.003 [head]; P < 0.001 [trunk]; P = 0.091 [Proximal extremity]). Nevi sized 60 cm or more were significantly deeper than those measuring 20-29.9 cm (P = 0.035). An interaction between size and location existed (P < 0.001). Trunk and distal extremity lesions consistently exhibited uniform thickness regardless of lesion size, whereas head and proximal extremity lesions showed variations in thickness based on lesion size.

CONCLUSION

GCMNs have differences in thickness according to location and size. Therefore, it is necessary to devise an approach optimized for each patient to treat GCMN. In the study, it was emphasized that the thickness of GCMN is correlated with clinical factors, specifically the location and size of the nevus. Consequently, these findings underscore the need for individualized treatment plans for effective surgical intervention.

Clinical study on the role of platelet-rich plasma in human acellular dermal matrix with razor autologous skin graft repair of giant congenital pigmented nevus in children

BACKGROUND

NA OBJECTIVE: Evaluate the safety and feasibility of platelet-rich plasma (PRP) in the treatment of giant congenital melanocytic nevi (GCMN) in children with human acellular dermal matrix (HADM) transplantation.

PATIENTS AND METHODS

A total of 22 children with GCMN were included in the study. They were divided into an experimental and a control group. The experimental group used the method of HADM with Razor Autologous Skin Graft combined with PRP to repair skin and soft tissue defects after giant nevus resection (Group A, n = 11). The control group was treated with HADM with Razor Autologous Skin Graft (Group B, n = 11) only. To compare the survival rate of skin grafts, we used the Vancouver Scar Scale (VSS) for the postoperative skin graft area and the Patient and Observer Scar Assessment Scale (POSAS) to compare the two groups of patients.

RESULTS

There was no statistically significant difference in age, gender, location of giant nevi, and pathological classification between Group A and Group (P > 0.05). The survival rate of skin grafting and the VSS and POSAS scores of scar tissue in group A were superior to those of group B (P < 0.05).

CONCLUSIONS

PRP has improved the survival rate of composite skin grafting in children with GCMN, and long-term satisfactory prognosis of scar healing. Therefore, we consider this treatment method a valuable contribution to clinical practice.

Updates in the Management of Congenital Melanocytic Nevi

Congenital melanocytic nevi (CMN) carry an increased risk of melanoma and may be disfiguring, and consensus regarding treatment recommendations is lacking. While clinical monitoring is the standard of care, many caregivers are interested in its removal to prevent psychosocial burden or to decrease risk. Although melanoma can occur regardless of CMN removal, there are a variety of treatments that may offer improved cosmesis or local symptom control, including surgical excision, laser therapy, and other superficially destructive techniques. Regardless of the selected management, these patients are monitored for ongoing melanoma risk. An extensive discussion with families regarding the risks and benefits of observation versus active intervention is essential. To facilitate these discussions, we herein summarize current CMN management strategies and considerations.

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.

Surgery or Not? A Systematic Review of Facial Congenital Melanocytic Nevi Treatment Patterns and Outcomes

BACKGROUND

Treatment management for congenital melanocytic nevi (CMN) on the face (FCMN) is highly variable and requires a thorough assessment of multiple factors. To date, a systematic review of FCMN treatment is lacking. The purpose of the present study was to elucidate the frequency, variety, and outcomes of treatment modalities for FCMN with different levels of complexity.

METHODS

A comprehensive review of Pubmed, Embase, and Google Scholar databases from 1950 to 2022 was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Articles reporting on FCMN treatment approaches, outcomes, and associated complications were screened and data were extracted according to inclusion criteria. Data were tabulated for thematic analysis of FCMN treatment types, anatomic locations, outcomes, and complications.

RESULTS

Of the 561 studies retrieved, 34 met inclusion criteria including 19 surgical treatments, 14 nonsurgical treatments, and one combined surgical and nonsurgical treatment study, totaling 356 patients. The majority of treated FCMN were small-to-medium-sized (56%). Facial CMN treated conservatively were mostly located on the cheek (27%) and/or perinasal region (21%), whereas FCMN treated with surgery were primarily located in the periorbital region (44%) and/or the cheek (17%). Across all treatment cohorts, 22% of patients experienced at least one complication, with 12% of complications experienced by patients treated by surgery.

CONCLUSIONS

There is a greater need for standardized FCMN nomenclature that encompasses nevi pattern, dimensions, anatomical coverage, and quantitative measurements of treatment outcome. Future studies should focus on identifying anatomic locations of FCMN that are more prone to complications and determine which treatment approach optimizes outcomes.

A high-hydrostatic pressure device for nevus tissue inactivation and dermal regeneration for reconstructing skin defects after giant congenital melanocytic nevus excision: a clinical trial

Background

A novel treatment has been developed to reconstruct large skin defects caused by the excision of giant congenital melanocytic nevi. It involves the reimplantation of high-hydrostatic pressurized nevus tissue as a cell-inactivated autologous scaffold for dermal regeneration, followed by the implantation of cultured epithelial autografts on the regenerated dermis. Because this treatment has shown promise in a first-in-human clinical trial which used a prototype pressure machine, a novel pressure device was specifically designed for clinical use.

Methods

In a prospective investigator-initiated clinical trial involving three patients, we evaluated the safety and efficacy of the skin regeneration treatment using a pressure device. All three patients underwent surgical excision of the nevus tissue, primary reimplantation of the inactivated nevus tissue, and secondary implantation of cultured epithelial autografts.

Results

Engraftment of inactivated nevus tissue and cultured epithelial autografts was successful in all three cases, with over 90% epithelialization at 8 weeks post-surgery. No serious adverse events or device malfunction were observed during the trial.

Conclusion

The novel pressure device safely and effectively enabled dermal regeneration using the nevus tissue as an autologous scaffold. This innovative approach offers several advantages, including reduced invasiveness due to minimal sacrifice of normal skin for skin grafting and high curative potential resulting from full-thickness removal of the nevus tissue.

Surgical Therapy of Congenital Nevi in the First Year of Life-Psychological Impact on Parents

BACKGROUND

The birth of a child with a congenital melanocytic nevus (CMN) can lead to distress in the parents. Surgical treatment of CMN can begin in infancy.

OBJECTIVES

To provide insight into the perspective of parents of children with CMN regarding their experienced psychological burden and motivation to undergo surgery as well as their satisfaction.

METHODS

Retrospective analysis of patient data of infants (< 1 year of age), who were surgically treated by power stretching for CMN using subcutaneous infiltration anesthesia (SIA) from 01/01/2020 to 08/31/2021. To evaluate the parent's motivation and psychological burden during the surgical treatment of their child, a questionnaire was designed to interview them in a standardized telephone-based interview.

RESULTS

Out of 45 interviewed parents, 62.2% indicated "severe" or "very severe" distress at the time of their child's birth. Distress was mostly reduced by information about diagnosis and treatment (n = 34) and treatment-progress (n = 27). Stigmatization was experienced by 35.6% of parents. 84,5% of parents were highly satisfied with early initiation of surgical therapy. 69% felt "very satisfied" or "satisfied" with the outcome of surgery. Motivation for surgical therapy was concern about malignant transformation of the, possible stigmatization of the child due to the nevus, while most of the parents (73.3%) mentioned both.

CONCLUSIONS

Surgical treatment of CMN by power stretching in SIA in infancy is associated with high levels of satisfaction among the children's parents. Early initiation of surgical therapy and education about the diagnosis can reduce the psychological burden of the parents and can prevent psychosocial problems in affected children.

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.

Transcriptomic analysis of mRNA expression in giant congenital melanocytic nevi

BACKGROUND AND OBJECTIVE

GCMN is a sporadic disease with an incidence ranging from 1/20,000 to 1/500000. So far, several studies have found that GCMN is related to somatic mutations, but most of them have focused on known pathogenic genes, and transcriptome sequencing based on large datasets is relatively uncommon. At present, the use of next-generation sequencing technologies and bioinformatics platforms makes genomic information study more comprehensive and efficient. In this study, the transcriptome differences between GCMN lesions and surrounding normal skin tissues were investigated using high-throughput transcriptome sequencing, and hub genes and pathways related to pathogenesis were identified, providing a theoretical foundation for further research into the pathogenesis of GCMN.

METHODS

Pathological skin tissue and surrounding normal skin tissue from GCMN patients, namely the pathological group (PG) and the control group (CG), were obtained. 1. All specimens were stained with HE to ensure that the samples met the experimental requirements. 2. Ten pairs of specimens were selected for high-throughput transcriptome sequencing, and the differentially expressed genes (DEGs) between the PG and the CG were obtained. The DEGs were analyzed by clusterProfiler R software for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. The function of the subnetwork was analyzed and the hub genes were identified by the STRING database and Cytoscape software. 3. The expression differences of hub genes PTGS2, EGF, and SOX10 in pathological skin tissues and normal skin tissues were verified by qRT-PCR and immunofluorescence staining.

RESULTS

1. HE staining revealed a lot of melanocytes in the dermis and subcutaneous tissues. They were found around the hair follicles, sweat glands, sebaceous glands, and blood vessel walls, or in a specific pattern. 2. The screening threshold was set at p<0.01 and |log2fc|<1, and a total of 1163 DEGs were discovered between the PG and CG, with 519 genes up-regulated and 644 genes down-regulated in the pathological tissues. According to the GO functional analysis, 29 biological processes, 18 cell compositions, and 17 molecular functions were significantly enriched, with the majority of them being related to keratinocytes and the extracellular matrix. There were 779 nodes and 2359 interactions in the protein interaction network. Using the MCODE plug-in, the network was divided into 25 functional clusters. According to ClueGO results, Cluster5 was involved in melanin biosynthesis and melanocyte proliferation. Using 11 operation methods in the Cytohubba plug-in, PTGS2, EGF, and SOX10 in Cluster5 were chosen as hub genes. 3. qRT-PCR and immunofluorescent staining revealed that compared to normal skin tissue, the expression of SOX10 was significantly up-regulated, and the expression of PTGS2 and EGF was significantly down-regulated in pathological skin tissue(P<0.001).

CONCLUSIONS

In GCMN, keratinocytes and extracellular matrix may directly and indirectly affect melanocyte activity. PTGS2, EGF, and SOX10 are important genes and significantly differentially expressed in pathological and normal skin tissues. These findings may serve as a springboard for future research.

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.

Care of Congenital Melanocytic Nevi in Newborns and Infants: Review and Management Recommendations

A pediatric dermatology expert working group performed a narrative review to describe care related to congenital melanocytic nevi (CMN) in neonates and infants. There are no published guidelines for most aspects of care, including routine skin care and visit intervals. Few guidelines exist for surgical management; newer recommendations favor conservative practice. Emerging evidence contributes to recommendations for screening MRI to evaluate for neural melanosis and related central nervous system complications, however, more research is needed. Risk for melanoma is generally low, but those with large, giant, or multiple CMN have a higher risk. Multidisciplinary care, with a focus on family and patient preferences, is of paramount importance. Without standardized screening and management guidelines, questions abound regarding appropriate physical examination intervals, potential treatment including full or partial excision, timing and frequency of imaging, melanoma risk, and assessment for neural melanosis. This review highlights the current state of knowledge concerning care of patients with CMN, reveals gaps in the literature surrounding skin care, and provides management recommendations. We additionally discuss cutaneous complications of CMN, such as pruritus, hypertrichosis, and wound healing. Resources and references for families and providers can help patients navigate this sometimes challenging diagnosis. Finally, we contribute expert care recommendations to the current body of literature as a foundation for the development of future, more comprehensive care guidelines.

Neonatal Curettage of Large to Giant Congenital Melanocytic Nevi Under Local Anesthetic: A Case Series With Long-Term Follow Up

Background

Neonatal curettage of large to giant congenital melanocytic nevi (L-GCMN) is a simple, minimally invasive procedure typically performed within the first 2 weeks of life.

Objectives

To retrospectively review our experience with serial curettage of L-GCMN in the neonatal period performed under local anesthesia and their long-term outcomes.

Methods

Curettage was performed by a single pediatric dermatologist on nine neonates with L-GCMN under local anesthetic and with oral analgesia between 2002 and 2016 in Red Deer, Alberta, Canada. Patient charts were reviewed retrospectively to assess patient and procedure characteristics, tolerability, safety, cosmetic and functional outcomes, and malignant transformation.

Results

Patients were treated with an average of 6 curettage sessions (range 3 to 15) to remove the majority or entirety of the nevus. All patients tolerated local anesthesia well. The most common adverse event of the procedure was transient neutropenia. Two patients developed positive bacterial cultures without clinical signs of infection, treated with antibiotics. All curetted specimens demonstrated benign pathology. Patients were followed annually thereafter, for an average of 6 years. Eight patients with L-GCMN of the trunk had minimal to partial repigmentation with good cosmetic outcome. One patient had recurrence of a facial nevus. None of the patients developed cutaneous malignant melanoma.

Conclusions

Curettage appears to be a safe and effective treatment option for select cases of L-GCMNs of the trunk. We do not recommend the procedure for face or scalp CMN. This procedure can be performed under local anesthesia with serial curettage to avoid potential risks of general anesthesia.

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.

Cultured epithelial autografts for the treatment of large-to-giant congenital melanocytic nevus in 31 patients

Introduction

Giant congenital melanocytic nevus (GCMN) is a large melanocytic nevus, and its full-thickness removal is usually difficult due to the lack of skin available for reconstruction. Curettage is an alternative approach in cases of GCMN to remove the superficial dermis above the cleavage plane with a curette in the neonatal period, and its major complications include repigmentation, retarded epithelization, and hypertrophic scar formation. In Japan, the JACE® cultured epidermal autograft (CEA) was approved and covered by public healthcare insurance for the treatment of congenital melanocytic nevus (CMN) that is difficult to treat with conventional methods in 2016. We have used CEA for wounds after curettage in the neonatal period or following ablation after the neonatal period in combination with laser therapies to reduce the above-mentioned complications.

Methods

In this study, we summarized all consecutive CMN patients treated using CEA from December 2016 to April 2019 and evaluated the duration required for epithelialization, incidence of hypertrophic scar, and color change in the target nevus by comparing the L∗ values one year later between the Curettage group, the non-Curettage group with initial treatment or the subsequent group.

Results

No significant differences were seen in the epithelization period or incidence of hypertrophic scars among the groups, but the color of the target nevus was improved significantly in the Curettage group (p < 0.01) and non-Curettage group with initial treatment (p < 0.01).

Conclusions

In conclusion, CEA seems to accelerate epithelization after curettage or ablation of CMN, and this treatment could improve the color of CMN when applied initially.

A Novel Treatment for Giant Congenital Melanocytic Nevi Combining Inactivated Autologous Nevus Tissue by High Hydrostatic Pressure and a Cultured Epidermal Autograft: First-in-Human, Open, Prospective Clinical Trial

BACKGROUND

Giant congenital melanocytic nevi are large skin lesions associated with a risk of malignant transformation. The authors developed a novel treatment to reconstruct full-thickness skin defects by combining an inactivated nevus as the autologous dermis and a cultured epidermal autograft. The first-in-human trial of this treatment was performed.

METHODS

Patients with melanocytic nevi that were not expected to be closed by primary closure were recruited. The full-thickness nevus of the target was removed and inactivated by high hydrostatic pressurization at 200 MPa for 10 minutes. The inactivated nevus was sutured to the original site, and a cultured epidermal autograft was grafted onto it 4 weeks later. Patients were followed for up to 52 weeks.

RESULTS

Ten patients underwent reimplantation of the pressurized nevus, and one patient dropped out. The recurrence of nevus at 52 weeks was not detected by pathological diagnosis in any patients. The L* value at 52 weeks was significantly higher than that of the target nevus. One patient received skin grafting due to contracture of the reconstructed skin. The epithelized area of the reconstructed skin, as the percentage of the original target nevus, was 55.5 ± 19.4 percent at 12 weeks and 85.0 ± 32.4 percent at 52 weeks.

CONCLUSIONS

The inactivated nevus caused inflammation and contracture for several months. However, no recurrence was observed, and combination therapy using an inactivated nevus with a cultured epidermal autograft may therefore be a novel treatment of giant congenital melanocytic nevi.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

A Case of Giant Congenital Melanocytic Nevus Treated with Combination Therapy of Autologous Mesh-skin Grafts and Cultured Epithelial Autografts

Surgical excision of a giant congenital melanocytic nevus (GCMN) results in a full-thickness skin defect that is usually difficult to reconstruct even with tissue expansion or skin grafting. Here, we report the first case of GCMN treated with a combination of cultured epithelial autografts (CEAs) and mesh-skin grafts to reconstruct a large skin defect after surgical excision. A 14-month-old girl had a GCMN occupying 20% of the total body surface area of her neck and back. A 5-stage, full-thickness excision was performed between the age of 14 and 25 months. In each intervention, the wound after excision was covered with 1:6 mesh-skin grafts and CEAs, except for the neck, where patch skin grafts and CEAs were used. The skin grafts and CEAs were engrafted without shedding and epithelialization was completed within 3-4 weeks. Eighteen months after the last surgery, a mesh-like scar remained, with no recurrence or severe contracture observed. The cosmetic appearances of the donor sites (the scalp and lower abdomen) were acceptable. The application of CEAs with mesh-skin grafts has been established for the treatment of severe burns. This combined method also provides a possible option for the treatment of GCMNs.

Giant Congenital Melanocytic Nevus in a Chinese Newborn

Giant congenital melanocytic nevus (GCMN) is a rare birthmark disorder that reportedly affects 1 in 20,000-500,000 live births. Here, we present a case of GCMN in a 1-day-old newborn that covered the entire abdomen, reaching the thigh and chest, and laterally toward the backward aspect of the trunk to involve the entire back and buttocks. We discuss the diagnostic and treatment approach.

Inactivated Nevus Tissue with High Hydrostatic Pressure Treatment Used as a Dermal Substitute after a 28-Day Cryopreservation Period

Background

Giant congenital melanocytic nevi (GCMN) treatment remains controversial. While surgical resection is the best option for complete removal, skin shortage to reconstruct the skin defect remains an issue. We report a novel treatment using a high hydrostatic pressurization (HHP) technique and a cryopreservation procedure. However, cryopreservation may inhibit revascularization of implanted nevus tissue and cultured epidermal autograft (CEA) take. We aimed to investigate the influence of the cryopreservation procedure on the HHP-treated dermis specimen and CEA take on cryopreserved tissue.

Methods

Nevus tissue harvested from a patient with GCMN was inactivated with HHP of 200 MPa and then cryopreserved at -30°C for 28 days. The cryopreserved specimen was compared with fresh (HHP-treated without cryopreservation) tissue and with untreated (without HHP treatment) tissue to evaluate the extracellular matrix, basal membranes, and capillaries. Cultured epidermis (CE) take on the cryopreserved tissue was evaluated following implantation of the cryopreserved nevus tissue with CE into the subcutis of nude mice.

Results

No difference was observed between cryopreserved and fresh tissue in terms of collagen or elastic fibers, dermal capillaries, or basement membranes at the epidermal-dermal junction. In 4 of 6 samples (67%), applied CE took on the nevus tissues and regenerated the epidermis in the cryopreserved group compared with 5 of 6 samples (83%) in the fresh group.

Conclusion

Cryopreservation at -30°C for 28 days did not result in significant damage to inactivated nevus tissue, and applied CE on the cryopreserved nevus tissues took and regenerated the epidermis. Inactivated nevus tissue with HHP can be used as a dermal substitute after 28-day cryopreservation.

Cosmetically Challenging Congenital Melanocytic Nevi

BACKGROUND

Congenital melanocytic nevi (CMN) have a 1% to 5% lifetime risk for malignant transformation, with 50% of transformations occurring before the age of 5 years.The aim of this study is to assess the risk of melanoma development in pediatric patients with facial CMN involving the eyebrows, eyelid margins, and nasal alae where a margin of CMN was not excised to preserve these structures.

METHODS

A retrospective chart review of all pediatric patients with CMN from 1986 to 2014 was performed to review demographic information, diagnosis, and number of surgeries. Patients' clinical photographs were evaluated for residual nevi after completion of the treatment.

RESULTS

More than 950 medical charts of patients with CMN of the face area were reviewed. We identified 32 patients (13; 41% male) that met the study criteria with pathology-confirmed diagnosis of facial CMN with an average age of 4.4 years (3.3 months-15.8 years) at the time of initial surgery. The CMNs were classified into small (1; 3%), medium (14; 44%), large (14; 44%), and giant (3; 9%) based on their projected adult sizes. No patients developed melanoma within the small residual lesions left over the eyebrows and eyelids and inside nostrils at an average follow-up time of 5.6 (1.0-14.4) years and average age of 9.6 (1.8-19.2) years at the time of last follow-up.

CONCLUSIONS

Although a lifelong risk of malignant transformation of the residual CMN cannot be concluded, our results found no transformation in follow-up visits at an average age beyond the highest risk of melanoma development in childhood. We feel that leaving residual lesions on the face in areas of important anatomic structures for better cosmetic outcome is an acceptable risk.

Congenital melanocytic nevi

PURPOSE OF REVIEW

To update pediatric providers on new developments in our understanding of the clinical presentation, genetics, and systemic risks associated with congenital melanocytic nevi (CMN).

RECENT FINDINGS

CMN are primarily caused by sporadic postzygotic somatic mutations, most frequently in NRAS, and studies of the genetic underpinnings of CMN have demonstrated a diverse array of genetic drivers. The primary complications of large and giant CMN include neurocutaneous melanocytosis and malignant melanoma. Abnormalities in CNS MRI may predict a worse clinical course for patients and increased risk of melanoma. Targeted therapies of the MEK pathway have begun to be studied for the treatment of CMN and prevention of associated complications.

SUMMARY

Patients with large and giant CMN should be managed by an interdisciplinary care team for the monitoring of dermatologic, neurologic, and psychosocial concerns. Ongoing research is underway to better characterize the genetic drivers of CMN and to better guide development of targeted therapeutics.

Simplified management of a giant forehead congenital nevus allows for early reconstruction

We report simplified surgical management of giant congenital forehead nevus that customarily requires the use of tissue expander for complete excision. Commencing treatment at the age of 3 months, the TopClosure tension relief system (TRS) was applied as an external tissue expander allowing preoperative skin stretching by mechanical creep. This was followed by partial excision of the nevus. Intraoperative stress-relaxation allowed further expansion of the skin. Postoperative wound closure was secured with the aid of the TRS. Repeated, six simple staged excisions of the forehead lesion and a minor skin graft to the eyelid part, allowed for delayed primary closure of the entire lesion by the age of 2. This simple alternative approach, which allows the early start and early conclusion of the reconstructive process, should be considered as the primary option in the treatment of these patients.

Surgical treatment of children and youth with congenital melanocytic nevi: self- and proxy-reported opinions

PURPOSE

The role of surgery in the management of congenital melanocytic nevi (CMN) is controversial. Data on surgical outcomes and predictors of satisfaction remain scarce.

METHODS

An online survey was employed following worldwide recruitment of youth aged 14-25 years (n = 44) and parents of children ≤ 18 years (n = 249) with CMN to query patterns of treatment and satisfaction with and opinions about the benefits of surgery.

RESULTS

In proxy-reports, 121 of 249 (49%) and in self-reports 30 of 44 (75%) participants underwent CMN excision. The most common reasons for surgery were psychosocial determinants, aesthetic improvement, and melanoma risk reduction. The overall satisfaction with surgical management was good, although no predictors for satisfaction could be identified. Higher current age of the child was found to predict decision regret in proxy-reports. Most participants indicated that having a scar is more socially acceptable than a CMN. Opinions differed on whether surgery should be deferred until the child is old enough to be involved in the decision-making process.

CONCLUSIONS

Whether and when to perform surgery in children with CMN is a multifaceted question. Awareness of common concerns as well as risks and benefits of surgery are essential to ensure critical reflection and balanced decision-making.

A large-scale collection of giant congenital melanocytic nevi: Clinical and histopathological characteristics

Giant congenital melanocytic nevi (GCMN) place a heavy psychological burden on patients due to their poor cosmetic appearance. The histopathological characteristics of GCMN have remained largely elusive. The present study investigated the histopathological characteristics of GCMN in association with their clinical appearance. A total of 98 patients diagnosed with GCMN were included in the present study and their clinical features were collected from their records. Lesion specimens were obtained and stained for histopathological analysis. Regarding the microscopic appearance of GCMN, nevi cells in the whole dermis exhibited different patterns than those in healthy tissues. Most GCMN cases featured a sub-epidermal non-involvement zone, which implies an early occurrence in embryo development. Darker nevi exhibited a higher density of infiltrated nevi cells and more pigment deposition; this appears to induce a poor skin texture. Chemical peeling and laser therapy only partly removes pigment particles and nevi cells in the upper portion of the dermis. The clinical features of GCMN are associated with the histopathological characteristics, and non-surgical therapy cannot remove the nevus cells in the deep dermis.

Simple and efficient method for consecutive inactivation-cryopreservation of porcine skin grafts

We previously reported that inactivation treatment by high hydrostatic pressurization (HHP) has potential utility as a novel skin regeneration therapy for various skin tumors. In this study, we evaluated whether glycerol-cryopreservation could be applied in order to preserve inactivated skin by HHP using a porcine model. Twenty full-thickness skin grafts (1.5 × 1.5 cm) were prepared from a minipig. The skin samples were inactivated by the HHP in normal saline or glycerol/fructose solution, followed by cryopreservation for 5 weeks at - 80 °C in each same solution. Another 10 grafts immediately after inactivation were prepared as non-cryopreserved controls. Nine grafts in each group were randomly implanted on the fascia of a host pig and removed at 1, 4 and 11 weeks after grafting. All grafts showed engraftment macroscopically. Hematoxylin eosin staining showed the cellular components in all areas of the dermis at 4 and 11 weeks after grafting, and immunohistochemical staining for CD31 showed the presence of capillaries in the grafts in all groups. The surface and cross-sectional areas of grafts in the normal saline solution cryopreserved group decreased between 1 and 11 weeks, whereas these areas in the glycerol cryopreserved group did not decrease significantly. Glycerol cryopreservation may therefore be a simple and efficient method for preserving porcine skin inactivated by HHP.

Management of congenital melanocytic nevi in the plastic surgery clinic: Families' expectations and their persistent concern about malignancy

BACKGROUND

Children with congenital melanocytic nevi (CMN) were historically managed with surgical removal to lower the risk of malignant transformation. The evolving literature over the last decade has indicated a significantly lower risk than previously estimated. Indications for excision currently revolve around aesthetic and psychosocial concerns. This study describes and evaluates the perspectives and expectations of patients and families referred to a pediatric plastic surgery clinic on CMN management.

METHOD

A two-part questionnaire was administered before and after an initial clinic appointment to evaluate patient and family concerns of lesion growth, risk of malignancy, treatment expectations, and stigmatization.

RESULTS

Thirty questionnaires were completed for 11 male and 19 female patients, mean age 9.2 years (1-25). Referring doctors (majority dermatologists) were rarely concerned about malignancy (8%), but parents listed it as a top reason for wanting the CMN removed (37%) and the most common expectation for the visit followed by information about surgical options and outcome. Before the clinic, 93% were at least "slightly" worried about CMN growth and 96% about malignancy, whereas 63% and 72%, respectively, after the clinic.

CONCLUSIONS

Families want information about surgical excision and are concerned about malignancy, indicating lingering misinformation or misconception about melanoma risk. For the majority, CMN removal remains at least slightly important, presumably for aesthetic reasons and remaining concern about malignancy. Involved health care professionals should assure reliable and coherent patient information about MM risk, indications for surgery and expected outcome to best support families' decision-making.

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.

[Congenital giant melanocytic nevi]

The paper describes a case of a rare tumor disease with massive involvement of the skin, mainly that of the occipital head and brain and liver tissues in a newborn infant. It considers the morphological and immunohistochemical characteristics of a giant tumor cell nidus in the skin of the occipital head.

Malignant Transformation of a Multi-Operated Divided Nevus of the Eyelids

A woman in her early fifties had regular follow-up for a medium-sized divided nevus of the eyelids which had undergone several surgical excisions during childhood for functional and esthetic reasons. Malignant transformation of the nevus occurred in the inferior eyelid, with the appearance of a new pigmented flat lesion. Histology showed in situ melanoma, and an NRAS activating mutation was found. A full-thickness excision of the inferior eyelid was performed, followed by reconstruction. Local recurrence of the melanoma occurred 1 year after surgery. Lifelong follow-up of divided nevi of the eyelids is recommended, even if very few cases of malignant transformation have been reported so far.

A case report of the first application of culture epithelial autograft (JACE®) for giant congenital melanocytic nevus after its approval in Japan

In Japan, the JACE^® cultured epidermal autograft (CEA) was approved and covered by public healthcare insurance for use in the treatment of giant congenital melanocytic nevus (GCMN) in 2016. We herein report the results of the application of JACE^® after curettage and Q-switched ruby laser therapy. The current patient was the first patient with GCMN to be treated with JACE^® since its approval. A 3-month-old girl had a hairy GCMN of 9.5 cm in diameter from her cheek to her temple on the left side of her face. We first performed curettage of the nevus on the temple and applied irradiation using a Q-switched ruby laser; however, erosion relapsed at 2 months after first surgery. After preparing JACE^®, we performed curettage a second time at 7 months with irradiation of a Q-switched ruby laser and the application of the CEA. The CEA took successfully and the wound was completely epithelized at 1 week after grafting. Re-pigmentation is an important issue that remains to be solved; however, overcoming this would allow for a deeper abrasion or more intense laser irradiation to be performed in cases in which CEA will be subsequently applied.

Melanin pigments in the melanocytic nevus regress spontaneously after inactivation by high hydrostatic pressure

We report a novel treatment for giant congenital melanocytic nevi (GCMN) that involves the reuse of resected nevus tissue after high hydrostatic pressurization (HHP). However, the remaining melanin pigments in the inactivated nevus tissue pose a problem; therefore, we performed a long-term observation of the color change of inactivated nevus tissue after HHP. Pressurized nevus specimens (200 MPa group, n = 9) and non-pressurized nevus tissues (control group, n = 9) were subcutaneously implanted into nude mice (BALB/c-nu) and then harvested 3, 6, and 12 months later. Color changes of the nevus specimens were evaluated. In the 200 MPa group, the specimen color gradually regressed and turned white, and brightness values were significantly higher in the 200 MPa group than in the control group after 6 months. This indicated that melanin pigments in the pressurized nevus tissue had spontaneously degraded and regressed. Therefore, it is not necessary to remove melanin pigments in HHP-treated nevus tissue.

The Alteration of the Epidermal Basement Membrane Complex of Human Nevus Tissue and Keratinocyte Attachment after High Hydrostatic Pressurization

We previously reported that human nevus tissue was inactivated after high hydrostatic pressure (HHP) higher than 200 MPa and that human cultured epidermis (hCE) engrafted on the pressurized nevus at 200 MPa but not at 1000 MPa. In this study, we explore the changes to the epidermal basement membrane in detail and elucidate the cause of the difference in hCE engraftment. Nevus specimens of 8 mm in diameter were divided into five groups (control and 100, 200, 500, and 1000 MPa). Immediately after HHP, immunohistochemical staining was performed to detect the presence of laminin-332 and type VII collagen, and the specimens were observed by transmission electron microscopy (TEM). hCE was placed on the pressurized nevus specimens in the 200, 500, and 1000 MPa groups and implanted into the subcutis of nude mice; the specimens were harvested at 14 days after implantation. Then, human keratinocytes were seeded on the pressurized nevus and the attachment was evaluated. The immunohistochemical staining results revealed that the control and 100 MPa, 200 MPa, and 500 MPa groups were positive for type VII collagen and laminin-332 immediately after HHP. TEM showed that, in all of the groups, the lamina densa existed; however, anchoring fibrils were not clearly observed in the 500 or 1000 MPa groups. Although the hCE took in the 200 and 500 MPa groups, keratinocyte attachment was only confirmed in the 200 MPa group. This result indicates that HHP at 200 MPa is preferable for inactivating nevus tissue to allow its reuse for skin reconstruction in the clinical setting.

An Exploratory Clinical Trial of a Novel Treatment for Giant Congenital Melanocytic Nevi Combining Inactivated Autologous Nevus Tissue by High Hydrostatic Pressure and a Cultured Epidermal Autograft: Study Protocol

Background

Giant congenital melanocytic nevi (GCMNs) are large brown to black skin lesions that appear at birth and are associated with a risk of malignant transformation. It is often difficult to reconstruct large full-thickness skin defects after the removal of GCMNs.

Objective

To overcome this difficulty we developed a novel treatment to inactivate nevus tissue and reconstruct the skin defect using the nevus tissue itself. For this research, we designed an exploratory clinical study to investigate the safety and efficacy of a novel treatment combining the engraftment of autologous nevus tissue inactivated by high hydrostatic pressurization with a cultured epidermal autograft (CEA).

Methods

Patients with congenital melanocytic nevi that were not expected to be closed by primary closure will be recruited for the present study. The target number of nevi is 10. The full-thickness nevus of the target is removed and pressurized at 200 MPa for 10 minutes. The pressurized and inactivated nevus is sutured to the original site. A small section of the patient’s normal skin is taken from around the nevus region and a CEA is prepared after a 3-week culturing process. The CEA is then grafted onto the engrafted inactivated nevus at four weeks after its retransplantation. The primary endpoint is the engraftment of the CEA at 8 weeks after its transplantation and is defined as being engrafted when the engraftment area of the inactivated nevus is 60% or more of the pretransplantation nevus area and when 80% or more of the transplanted inactivated nevus is epithelialized.

Results

The study protocol was approved by the Institutional Review Board of Kansai Medical University (No. 1520-2, January 5, 2016: version 1.3). The study opened for recruitment in February 2016.

Conclusions

This protocol is designed to show feasibility in delivering a novel treatment combining the engraftment of inactivated autologous nevus tissue and CEA. This is the first-in-man clinical trial of this treatment, and it should be a promising treatment of patients suffering from GCMN.

Trial Registration

University Hospital Medical Information Network: UMIN000020732; https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000022198 (Archived by WebCite at http://www.webcitation.org/6jLZH2vDN)