Dermoscopic Features of Small, Medium, and Large-Sized Congenital Melanocytic Nevi

Non-multiple medium-sized congenital melanocytic nevi: to excise or to follow up?

Introduction

Congenital melanocytic nevi (CMN) are benign lesions composed of clonal proliferations of melanocytes. Although medium-sized CMN are common and generally remain benign throughout a person's lifetime, they may be precursors of melanoma. There is a limited number of studies focused on the risk of melanoma in solitary, medium-sized, congenital melanocytic nevus; therefore, the incidence of malignant transformation and guidelines for treatment are not well established.

Aim

Prompted by the limited data, we conducted this study to gather more information about medium-sized CMN, to optimize clinical care. We share our analysis of surgically removed medium-sized CMN.

Material and methods

A total of 10 patients with non-multiple, medium-sized, congenital melanocytic nevus were included in this study. Lesions were removed using surgical procedures.

Results

In most of the cases the reason for excision of the medium-sized CMN was evolution of the lesion or aesthetic considerations reported by the patients. In 2 cases, due to the large size of the lesions, serial excisions were performed, while other CMN were removed surgically using simple excision technique. Eight of 10 medium-sized CMN were histologically described as benign, and 2 cases of malignant transformations were reported.

Conclusions

According to our clinical experience and knowledge, we recommend managing patients on an individual basis, taking into consideration multiple clinical attributes. In our opinion, long-lasting observation is the management of choice, and if there is need of surgery, we recommend total simple or staged excision depending on nevus size.

Real-time Intraoperative Dermoscopic Monitoring of Common Acquired Melanocytic Nevi Following Shave Excision

Background

The treatment of common acquired melanocytic nevus (CAMN) is mostly desired for cosmetic purposes due to which a number of "faster and less traumatizing" techniques have been developed. The major cause of recurrence is incomplete removal; there is a need for early detection of any residual pigment.

Aims and Objectives

This study aimed to assess the recurrence of common acquired melanocytic nevi and whether dermoscopy can be used as a noninvasive tool for the assessment of residual pigment following shave excision.

Materials and Methods

A total of 100 patients of age more than 18 years with clinical features suggestive of common acquired melanocytic nevi were enrolled in the study. The nevi were assessed clinically and dermoscopically and, if found benign, were excised using shave excision. The specimen obtained was sent for histopathological examination. Dermoscopy was used immediately after shave excision for observing any residual pigment and, if present, was removed using radiofrequency current. The patients were followed up at 6 and 12 weeks for recurrence.

Results

On histopathology, 87% nevi were intradermal, 8% were compound, and 5% had insufficient tissue for diagnosis, which were clinically diagnosed as junctional nevi. Dermoscopy immediately after shave excision helped in detecting residual pigment in 91% nevi, which was immediately ablated with radiofrequency, thus decreasing the risk of recurrences. Recurrences were seen in 33% nevi and all were intradermal with the presence of hair in the majority (66.67%) of them.

Conclusion

Shave excision is a minimally invasive and easily performed procedure. Dermsocopy can be used for assessing residual pigment after shave excision and thus reducing the risk of recurrences. On combining shave excision with radiofrequency ablation and assessing by dermoscopy, majority of patients were satisfied with the cosmetic results. Using dermoscope for follow-up helps in early recognition of recurrence and thus appropriate treatment can be provided at the earliest.

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.

Cutaneous Melanoma Arising in Congenital Melanocytic Nevus: A Retrospective Observational Study

BACKGROUND

Congenital melanocytic nevi (CMN) are benign proliferations of melanocytes usually present at birth. The magnitude of the melanoma risk for CMN is controversial, generating an ongoing debate on the best approach to manage these lesions.

OBJECTIVE

To perform a retrospective, observational study with the aim to evaluate the prevalence of CMN-associated melanomas in tertiary referral centers, as well as the eventual correlation between clinical, dermoscopic, and histological features of CMN-associated melanomas.

METHODS

A single-center retrospective observational study was performed on all clinical and dermoscopic images of histologically confirmed melanomas arising on CMN over a 14-year period (January 2005 to March 2019).

RESULTS

Our database included 2,159 melanomas in the considered period. Of those, 27 (1.3%) were CMN-associated melanomas. The mean age of patients with CMN-associated melanoma was 33 years (range, 11-70 years). The mean diameter of CMN-associated melanoma was 18 mm (range, 6 mm to 20 cm), and 56% were located on the back. Twenty-one (77.8%) of CMN-associated melanomas arose on small CMN (<1.5 cm), 5 (18.5%) on medium-sized CMN (1.5-19.9 cm), and 1 (3.7%) on a large/giant type (≥20 cm). The majority of CMN-associated melanomas (63%) exhibited a globular dermoscopic pattern in their benign part, while a blue-white veil and irregular blotches were the most frequent dermoscopic features in the malignant part. About three quarters of melanomas occupied 10-50% of the nevus surface. Breslow thickness was higher in melanomas involving less than 10% of nevus surface (mean thickness, 1 mm) than in those affecting 10-50 and >50% of the nevus surface (0.8 and 0.7 mm, respectively).

CONCLUSIONS

In our series, small CMN was the most frequent type of CMN-associated melanoma. Although the risk of melanoma is increasing by the increasing size of CMN, our finding is definitely related to the much higher prevalence of small CMN in the general population as compared to the prevalence of intermediate-sized and large CMN.

LIMITATIONS

Small sample size, single-center experience, retrospective design.

A practical review of dermoscopy for pediatric dermatology part I: Melanocytic growths

The value of dermoscopy in the detection of skin cancer is well established. Less is published on the utility of dermoscopy in the evaluation of pediatric skin disease. Our review (in two parts) aims to serve as an update on pediatric dermoscopy and to provide readers with a practical application for the use of dermoscopy in pediatric dermatology clinics. In part I, we propose a dermoscopy algorithm for pediatric skin disease and melanocytic growths, and in part II, we address vascular growths, common skin infections, and inflammatory conditions for which dermoscopy is valuable.