Nevi - when to refer.

PURPOSE OF REVIEW: Congenital melanocytic nevi (CMN) and acquired nevi are prevalent in pediatric populations, with distinct characteristics and management considerations. This chapter aims to equip pediatricians with knowledge to discern between benign and high-risk nevi, facilitating appropriate referrals and management within primary care settings. Risk factors associated with malignant melanoma (MM) underscore the importance of vigilant monitoring and early referral to dermatology for suspicious lesions. RECENT FINDINGS: Recent findings highlight the variability in CMN presentation and the evolving diagnostic strategies, emphasizing the need for multidisciplinary approaches to optimize patient outcomes. SUMMARY: Management of CMN involves tailored surveillance and intervention strategies, with an emphasis on early identification of high-risk features for MM and neurocutaneous melanosis (NCM). Pediatricians play a crucial role in advocating for sun protection practices and facilitating timely referrals, thereby contributing to the overall well being of pediatric patients with nevi.

Correlation between super-high magnification (400x) dermoscopy and reflectance confocal microscopy for the diagnosis of melanosis and other pigmented genital lesions.

The clinical diagnosis of pigmented genital lesions is challenging. Reflectance confocal microscopy (RCM) is effective for diagnosis but is limited in its application due to elevated costs. A more affordable dermatoscope with a 400x magnification (D400) has recently been brought to market. The aim of our study was to compare these two imaging techniques for the analysis of pigmented genital tumours. An observational, prospective and mono-centric study was carried out from October 2017 to May 2019, in which clinical, dermatoscopic (20x and 400x) and RCM data from 207 pigmented genital lesions were collected. The images generated via D400 and RCM were analysed by three expert investigators. Similarities between the criteria observed using D400 and RCM were evaluated by each investigator. In total, 207 lesions were included: 183 melanosis, 19 nevi, one basal cell carcinoma (BCC), two condylomas and two melanomas in situ. Our series correlates well with data found in the literature especially for the distribution of different lesions, their topography, and their aspect using x20 dermatoscopy and RCM. Pattern and cell criteria defined using RCM largely paralleled those observed with D400 for all three investigators. Correlation between D400 and RCM was moderate to strong with regards to the identification of the ring pattern and clustered round cells, strong for dendritic and plump cells, and perfect for isolated round cells and spindle cells. D400 is an easy-to-use, cost-effective alternative for the analysis of pigmented genital lesions, particularly for melanosis.

Co-occurrence of posterior chest wall pilonidal sinus with melanocytic nevus: a challenging presentation: a case report.

INTRODUCTION: To date, only a limited number of case reports have documented the co-occurrence of PNS and melanocytic nevus in the medical literature. This study aims to report an exceptionally rare case of posterior chest wall PNS in conjunction with a melanocytic nevus. CASE PRESENTATION: A 46-year-old female presented with a long-standing black lesion on her left upper posterior chest wall, that had become painful in the two months prior to presentation. There was a painful, dark blue, non-erythematous, and non-tender nodule on the left upper posterior chest wall. Based on the patient's desire for cosmetic purposes, the lesion was excised totally with primary closure under local anaesthesia. Histopathological examination revealed intradermal melanocytic nevus with inflamed pilonidal sinus. DISCUSSION: The rarity of posterior chest wall PNS associated with nevi poses unique diagnostic and therapeutic challenges for clinicians. The distinct anatomical location, different from the conventional region, and the rare association between the two conditions may delay accurate diagnosis and result in mismanagement or inappropriate interventions. CONCLUSION: The posterior chest wall PNS is another type of atypical PNS that is extremely rare. The association between PNS and blue nevus is a fascinating medical finding that deserves further investigation.

Schwannian and Perineuriomatous Differentiation in a Series of Giant Congenital Melanocytic Nevi.

ABSTRACT: Close relationship between melanocytes and neural cells is accepted to reflect their common derivation from the neural crest and tumors combining both elements. We present a series of 10 patients with giant congenital melanocytic nevi (CMN) in which a secondary proliferation (11 lesions) with schwannian and/or perineuriomatous differentiation developed in the course of the disease. The age of the patients (4 male and 6 female) at the time of surgery and histological assessment varied from 3 months to 57 years. Histopathologically, the following subgroups were delineated: (1) nodular/tumoriform "neurotization" in CMN, (2) diffuse neurofibroma-like proliferation within CMN, (3) plexiform neurofibroma-like proliferation within CMN, and (4) diffuse perineuriomatous (hybrid schwannomatous-perineuriomatous) differentiation in CMN. We review the pertinent literature, including the role of recently identified Schwann cell precursors which are believed to represent the nerve-associated state of neural crest-like cells that persists into later developmental stages.

A case of diagnostic uncertainty: High-grade melanocytoma versus balloon cell melanoma in a pediatric patient.

An 11-year-old female was referred from an outside institution after a diagnostic biopsy and subsequent excision of a progressively enlarging reddish-brown nodule demonstrated features concerning for a balloon cell nevus with severe atypia versus a high-grade melanocytoma. Upon review of the initial biopsy specimen and molecular data, we favored the diagnosis to be consistent with a high-grade melanocytoma with balloon cell changes while considering the possibility of balloon cell melanoma due to concerning histopathologic and genetic abnormalities. In this case study, we discuss critical diagnostic considerations in this rare pediatric case and highlight important pathologic and clinical features of melanocytomas and balloon cell melanoma.

Epidemiological characteristics and hospitalization burden analysis of pediatric inpatients with melanocytic nevi in China from 2016 to 2021: A nationwide retrospective study of 13,396 cases.

BACKGROUND: Melanocytic nevi typically appear in early childhood, and their removal is a common plastic surgery procedure performed on children. However, the epidemiological characteristics and hospitalization burden of children with melanocytic nevi have rarely been described in detail. METHODS: Medical records of pediatric inpatients with melanocytic nevi from January 1, 2016, to December 31, 2021, were collected from the Futang Research Center of Pediatric Development database in China. We then extracted and statistically analyzed the relevant information, including demographic characteristics, clinical information, hospitalization burden, and other basic information for each inpatient. RESULTS: Among the 13,396 inpatients with melanocytic nevi, the highest number of cases was found in East China, and most patients were residents of urban areas. Most hospitalized patients consisted of boys aged 7-12 years with melanocytic nevi. Lesion sites in the buttocks and lower limbs were most common among pediatric inpatients with melanocytic nevi. Compound nevi were the most common (38.50 %) histological subtype and the rate of conversion into melanoma was 1.02 % (137 inpatients) among pediatric inpatients with melanocytic nevi. The hospitalization burden for patients varied significantly based on factors such as the age of the patients undergoing surgery, year of hospitalization, site of the lesion, histological subtype, and surgical method. In general, if the patients' age was under 1 year, lesion site was located in face, and there was a need for excision combined with tissue expander can significantly increase the treatment fees for pediatric inpatients with melanocytic nevi. CONCLUSION: Given the increasing number and relatively large hospitalization burden among children with melanocytic nevi hospitalized in China, the government needs to pay more attention to this group and provide corresponding economic and policy support.

Histopathology of skin melanocytic lesions.

Melanocytic lesions are instable tumors, the genome of which and its changes determinate their morphology and biological properties. Intermediate lesions share histomorphological features of both, nevi and melanoma. Melanocytomas represent a group of them separated on the basis of recent molecular-biological studies. The article summarizes benign, intermediate, malignant and combined melanocytic skin lesions and offers practical recommendations for diagnosis.

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.

Molecular Markers in Melanoma Progression: A Study on the Expression of miRNA Gene Subtypes in Tumoral vs. Benign Nevi.

This study investigates the differential expression of miRNA gene subtypes in tumoral versus benign nevi in individuals with melanoma, aiming to identify clinically significant correlations that could serve as reliable markers for assessing tumor stage and progression. Conducted between 2019 and 2022, this descriptive, quantitative observational research analyzed 90 formalin-fixed paraffin-embedded (FFPE) samples from the Pius Brinzeu County Emergency Clinical Hospital, Timisoara, including 45 samples of advanced-stage melanoma and 45 samples of pigmented nevi. miRNA purification and analysis were performed using the miRNeasy Kit and the Human Cancer PathwayFinder miScript miRNA PCR Array, with statistical analysis (including logistic regression) to determine associations with cancer staging, such as high Breslow index risk, number of mitoses, and vascular invasion. After the analysis and comparison of 180 miRNA gene subtypes, we selected 10 of the most upregulated and 10 most downregulated genes. The results revealed that hsa-miR-133b, hsa-miR-335-5p, hsa-miR-200a-3p, and hsa-miR-885-5p were significantly upregulated in melanoma samples, with fold changes ranging from 1.09 to 1.12. Conversely, hsa-miR-451a and hsa-miR-29b-3p showed notable downregulation in melanoma, with fold changes of 0.90 and 0.92, respectively. Additionally, logistic regression analysis identified hsa-miR-29b-3p (OR = 2.51) and hsa-miR-200a-3p (OR = 2.10) as significantly associated with an increased risk of a high Breslow index, while hsa-miR-127-3p and hsa-miR-451a were associated with a reduced risk. Conclusively, this study underscores the significant alterations in miRNA expression in melanoma compared to benign nevi and highlights the potential of specific miRNAs as biomarkers for melanoma progression. The identification of miRNAs with significant associations to melanoma characteristics suggests their utility in developing non-invasive, cost-effective diagnostic tools and in guiding therapeutic decisions, potentially improving patient outcomes in melanoma management.

Evaluation of tubulin ß-3 and 5 hydroxy-methyl cytosine as diagnostic and prognostic markers in malignant melanoma.

Tubulin ß-3 staining pattern and staining intensity of 5-hydroxymethyl cytosine (5-hmC) are potential diagnostic and prognostic markers in melanocytic lesions that need further evaluation. Melanocytic nevi and primary cutaneous melanomas were immunohistochemically stained for tubulin-ß-3 and 5-hmC. Immunoreactivity and staining patterns were correlated with Breslow-thickness, clinical and pathological characteristics, and progression-free survival. Melanocytes showed positive tubulin ß-3 staining. However, in most nevi, tubulin ß-3 staining appeared as a gradient with intense cytoplasmic staining in cells of the superficial part of the lesion that faded to weak staining in the deep dermal part, while no gradient was found in deep penetrating nevi and melanomas. In 53 % of the melanomas, areas with loss of tubulin ß-3 staining were found. 5-hmC staining intensity was significantly higher in melanocytic nevi compared to melanomas. Breslow thickness in combination with low 5-hmC score and loss of tubulin-ß-3 staining was predictive for poor prognosis. As single markers, tubulin-ß-3 and 5-hmC can be useful to distinguish between melanocytic nevi and melanoma, but staining variability limits the use of 5-hmC. In melanomas measuring >1.5 mm, combination of low 5-hmC score and loss of tubulin-ß-3 staining may have prognostic value.

Application of dermoscopy and reflectance confocal microscopy in vivo in the evaluation of nevi in children.

BACKGROUND: Melanocytic nevi are frequently observed in the pediatric population. While newly acquired nevi can appear during childhood, congenital nevi can continue to grow and clinically change, making patient caregivers concerned. Reflectance confocal microscopy (RCM) in vivo is a noninvasive tool that might enhance the diagnostic accuracy of dermoscopy, reducing the rate of unnecessary surgical procedures. This study aimed to assess the utility of RCM in increasing the diagnostic accuracy of pediatric melanocytic nevi that show pigmentation changes or grow rapidly. METHODS: Pediatric patients who presented between January 2022 and February 2023 in a single institution with rapidly growing melanocytic nevi or nevi that presented changes in the pigmentation were included in the study. All nevi were evaluated by means of dermoscopy and RCM. RESULTS: Forty-two patients with a total of 42 melanocytic nevi were included. Most lesions showed a honeycombed pattern (n = 21, 50%). On RCM, only 3 of 42 nevi presented atypical cells within the epidermis (7.1%). Evaluation of the dermoepidermal junction (DEJ) revealed the predominance of the meshwork pattern (n = 22, 52.4%). Notably, features considered significant for atypical melanocytic nevi included 9 nevi with scant atypical melanocytes (21.4%) and 3 nevi with nonedge papillae (7.1%). None of the studied lesions required biopsy among this cohort. CONCLUSIONS: Most rapidly growing and clinically changing nevi rarely exhibit single atypical cells in the DEJ. The RCM served as a valuable adjunct to dermoscopy, allowing reassurance in the evaluation of these lesions.

Combined Melanocytic Nevus and Nevus Sebaceus: A Case Series and Review of the Literature.

ABSTRACT: Nevus sebaceus is a rare congenital hamartoma with clinical and histopathological features that change with puberty. It has been associated with a number of secondary neoplasms, most of which are thought to derive from follicular germ cells. In this article, the authors describe a total of 3 cases of combined melanocytic nevus and nevus sebaceus to highlight this rare finding.