Mimics of melanoma in reflectance confocal microscopy

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.

Melanoma: How and When to Consider Clinical Diagnostic Technologies

In response to rising rates of melanoma worldwide, novel non-invasive melanoma detection techniques are emerging to facilitate the early detection of melanoma and decrease unnecessary biopsies of benign pigmented lesions. Because they often report similar study findings, it may be difficult to determine how best to incorporate these technologies into clinical practice based on their supporting studies alone. As an expansion of the recent article by Fried et al.¹, which reviewed the clinical data supporting these non-invasive melanoma detection techniques, the first article in this continuing medical education series provides practical advice on how and when to use various non-invasive melanoma detection techniques into clinical practice.