Surface microscopy features of congenital nevi

Management of small and intermediate congenital nevi: a nationwide survey in Italy

OBJECTIVE

Small- and intermediate-sized congenital nevi (SCN and ICN) undergo periodic clinical monitoring or surgical excision. We analyzed the management of SCN and ICN in the Italian hospital network.

METHODS

A nationwide survey of a representative sample of centers was conducted. Data were analyzed grouping centers by melanoma incidence into high-volume (>25 diagnoses per year) and low-volume (≤ 25 diagnoses per year).

RESULTS

In the pediatric population, 11% of SCN and 22% of ICN are excised, the remainder undergoing clinical monitoring at intervals of 6 months to 2 years (SCN) and of 6 months to 1 year (ICN). In adults, 24% of SCN and 41% of ICN are excised. Clinical monitoring of SCN varies from 6-monthly (most common among low-volume hospitals) to every 2 years; preferred strategies for ICN are follow-up at 1 year (51%) or follow-up at 6 months (42%). For prophylactic surgery, complete excision is preferred.

CONCLUSIONS

The Italian hospital network values management and treatment of SCN and ICN. In most cases natural evolution prompts prophylactic excision. Clinical examination is an important monitoring tool, though follow-up frequency depends on the clinician's experience and practice.

Congenital melanocytic nevi: where are we now? Part I. Clinical presentation, epidemiology, pathogenesis, histology, malignant transformation, and neurocutaneous melanosis

Congenital melanocytic nevi (CMN) are present at birth or arise during the first few weeks of life. They are quite common, may have a heritable component, and can present with marked differences in size, shape, color, and location. Histologic and dermatoscopic findings may help suggest the diagnosis, but they are not entirely specific. CMN are categorized based on size, and larger lesions can have a significant psychosocial impact and other complications. They are associated with a variety of dermatologic lesions, ranging from benign to malignant. The risk of malignant transformation varies, with larger CMN carrying a significantly higher risk of malignant melanoma (MM), although with an absolute risk that is lower than is commonly believed. They may also be associated with neuromelanosis, which may be of greater concern than cutaneous MM. The information presented herein aims to help dermatologists determine when it is prudent to obtain a biopsy specimen or excise these lesions, to obtain radiographic imaging, and to involve other specialists (eg, psychiatrists and neurologists) in the patient's care.

Dermoscopic Features of Congenital Melanocytic Nevus and Becker Nevus in an Adult Male Population: An Analysis with a 10-Fold Magnification

BACKGROUND

Dermoscopic features of congenital melanocytic nevi (CMN) have been mostly assessed by high-resolution video-dermoscopy. However, optical dermoscopy with the 10-fold magnification is largely available. In some instances, the differential diagnosis between large CMN and Becker nevus (BN) may be difficult.

OBJECTIVE

The aims of this work were: (1) to assess by dermoscopy with the 10-fold magnification the morphological features which have been previously suggested as useful for the identification of CMN in high-resolution video-dermoscopy; (2) to search and point out the dermoscopic features of BN; (3) to explore dermoscopic differences between CMN and BN.

METHODS

The subjects were observed among about 23,000 consecutive young men assessed at the Draft Council's Medical Unit of the Italian Navy in Taranto for compulsory recruitment and referred to the Department of Dermatology of the Italian Navy Hospital for dermatological examination. Lesions were examined by the same observer using a dermatoscope with a 10-fold magnification, and both the dermoscopic criteria stated by the international Consensus Net Meeting on Dermoscopy and dermoscopic features previously suggested as useful for the identification of CMN by video-dermoscopy were recorded in a predisposed patient's card.

RESULTS

There were 127 male subjects, median age 19 years, with 127 CMN, measuring > or = 1.5 to < or = 19.9 cm in 78% and > or = 20 cm in 22% of cases, and 64 male subjects, median age 19 years, with 64 BN. In the sample of medium-sized and large CMN, dermoscopic features previously identified as characteristic of congenital lesions (i.e. target network, focal thickening of network lines, target globules, skin furrow hypopigmentation, focal hypopigmentation, hair follicles, perifollicular hypopigmentation, vessels and target vessels) were observed in sufficiently high rates. In the BN group, network, focal hypopigmentation, skin furrow hypopigmentation, hair follicles, perifollicular hypopigmentation and vessels were the main dermoscopic features. Focal thickening of network lines, globules, target globules, homogeneous diffuse pigmentation, hyperpigmented areas, blotches and target vessels were more frequently observed in CMN than in BN.

CONCLUSIONS

(1) The same dermoscopic features observed in small and medium-sized CMN by video-dermoscopy with high magnifications are also detectable in medium-sized and large CMN, employing the dermoscopy with the 10-fold magnification. (2) Network, focal, skin furrow and perifollicular hypopigmentation, hair follicles and vessels could be considered as peculiar dermoscopic features of BN. (3) Major differences in the frequency of dermoscopic characteristics were detected between CMN and BN, and dermoscopy seems to provide some diagnostic aid in differentiating CMN from BN in equivocal cases.

Instrument-, age- and site-dependent variations of dermoscopic patterns of congenital melanocytic naevi: a multicentre study

BACKGROUND

Recently, we identified and described dermoscopic aspects, present with a higher frequency in congenital melanocytic lesions with respect to acquired naevi. We also classified small- and medium-sized congenital naevi (CN) into nine subtypes according to their macroscopic and dermoscopic aspects.

OBJECTIVES

Because the recognition of dermoscopic features may be instrument dependent, in this study, we wanted to check whether dermoscopic patterns specific for CN can be identified in digital images acquired by means of different instruments. We also wanted to check the validity of our previously proposed classification and assess possible age- and site-dependent variations of dermoscopic patterns and naevus subtypes.

PATIENTS/METHODS

Images corresponding to 384 small- or medium-sized CN were collected in eight different centres employing four different instruments. Lesion images were evaluated and checked for the presence of specific dermoscopic criteria, classified, and compared with a database of 350 acquired naevi.

RESULTS

Specific and unspecific dermoscopic features were identifiable in images acquired by means of all four instrument types. The mean number of identified features per lesion did not vary according to the instrument employed for the acquisition of the images; however, it was lower for lesions recorded employing low magnifications. The previously proposed classification was easily applied to the whole image database. The variegated naevus type was identified as a highly specific clinical/dermoscopic pattern. Dermoscopic features varied according to age and location. The globular type prevailed in subjects under 11 years of age and on the trunk, whereas the majority of reticular lesions were located on the limbs.

CONCLUSIONS

Because definite clinical and histological criteria for the diagnosis of the congenital nature of naevi are lacking, the use of dermoscopy can be of great help in identifying those lesions where the presence of specific dermoscopic features makes the diagnosis of CN more likely. Moreover, dermoscopy can be useful both for the classification of lesions already identified as congenital according to definite clinical and anamnestic data and for a possible correlation of naevus phenotype and dermoscopic patterns to the risk of developing a malignant melanoma in prospective studies.

Is JPEG compression of videomicroscopic images compatible with telediagnosis? Comparison between diagnostic performance and pattern recognition on uncompressed TIFF images and JPEG compressed ones

Early melanoma diagnosis is an important goal for dermatologists. Polarized light systems are increasingly employed for dermatoscopic diagnosis of melanocytic lesions. For the purpose of teledermoscopy, whose importance is increasingly growing for consultation and teaching purposes, it is of utmost importance to establish whether, after compression, polarized light images maintain their informativeness. The aim of our study was to check the effects of compression on melanocytic lesion images acquired by means of a digital videomicroscope on the identification of morphological details of the image and on diagnostic accuracy. A total of 170 50-fold-magnified pigmented skin lesion images, acquired in Tagged Image File Format (TIFF) by a digital videomicroscope, were compressed using Joint Photographic Experts Group (JPEG) algorithms (compression factor 30). Two experts in videomicroscopy evaluated both original and compressed images twice by describing single lesion features and expressing a diagnosis. Reproducibility in the assessment of dermoscopic parameters and observer performance were studied by kappa statistics and Receiver Operating Characteristic (ROC) analysis. Both intra- and interobserver reproducibility in the assessment of morphological details were higher when TIFF images were considered, indicating a better image quality. Nonetheless, there was no significant difference in the diagnostic accuracy between uncompressed images and compressed ones, although the intraobserver reproducibility in the diagnostic judgement was higher for uncompressed images. Despite loss in image details, factor 30 compressed videomicroscopic images enable a good diagnostic accuracy.

Dermoscopy for Congenital Melanocytic Nevi

Small and medium congenital melanocytic nevi are relatively common but present a small but significant risk of malignant transformation. Because prophylactic excision of all nevi is impractical, dermoscopic evaluation has a role in the clinical decision-making process. Dermoscopy of benign congenital nevi reveals a globular or homogenous pattern, black or brown dots and globules, small milia-like cysts within the globules, and terminal hairs. Dermoscopic criteria of melanoma are outlined here, with discussion of common scoring methods, the seven-point checklist, the ABCD rule, pattern analysis, and the Menzies criteria. Serial examination of congenital nevi with dermoscopy and excision of those lesions with malignant criteria are useful in the management of congenital melanocytic nevi.

Congenital melanocytic nevi: treatment modalities and management options

Congenital melanocytic nevi can be cosmetically disfiguring, give rise to melanoma, and suggest the presence of neurocutaneous melanocytosis. Management decisions must be tailored for each patient and each nevus, taking into consideration the risk for developing malignancy, risk for developing symptomatic neurocutaneous melanocytosis, cosmetic implications of having the nevus, cosmetic implications of any resultant surgical scars from their removal, adverse effects that the nevus may have on psycho-social development, and the adverse effects and long-term sequelae of any surgical intervention. The advantages and disadvantages of different modalities used in the treatment of congenital melanocytic nevi are discussed. Organizational flow diagrams are presented to help clinicians in managing patients with different sized congenital melanocytic nevi.