A juvenile case of conjunctival atypical nevus

Abstract

Virtual slidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2973228795724608Melanocytic nevi are the most common tumors of the conjunctiva, accounting for 28% of all neoplastic lesions. These tumors, despite their benign behavior, share some atypical histological features with nevi found in other anatomic sites like the genital and acral regions, globally designated as nevi with site-related atypia. Moreover, in children and adolescents, rapidly growing conjunctival nevi show sometimes worrisome histological patterns in association with a prominent inflammatory infiltrate that may lead to diagnostic problems. In this paper we describe a juvenile compound nevus characterized by marked melanocytic atypia and severe inflammation, which can be considered a rare case of juvenile conjunctival atypical nevus. The final diagnosis relied on morphological and immunohistochemical characterization of the large epithelioid melanocytic cells, and on the results of FISH analysis.

Surgical treatment of conjunctival nevi in pediatric patients

“…Colarossi et al (8) observed that during growth and puberty, conjunctival lesions are often surrounded by inflammation, which mimics an increase in size and thus might raise a suspicion of malignancy. In the study by Aalkatan et al 4, histological findings of conjunctival pigmented nevi were studied separately in a subgroup of patients below 20 years of age.…”

“…The incidence of malignant conjunctival melanoma is extremely low in children. According to several authors, conjunctival nevus undergoes malignant transformation in only 1% of cases (1,3,8,9). There are only 29 reported cases of conjunctival melanoma in children aged 15 years or younger (4,11,14,15), and only 9 cases have been well-documented and described in detail.…”

“…The nevus becomes predominantly evident in childhood and usually remains stable over time (1,4,6,7). Histologically, conjunctival nevus is a proliferation of melanocytes within the basal layer of the conjunctiva (4,8) and its histological structure resembles the one of cutaneous nevi (1,6,8). Therefore, the most common classification of pigmented conjunctival nevi is based on the categories used for classification of cutaneous lesions.…”

“…In most publications, the authors distinguish three types of melanocytic conjunctival lesions i.e. junctional lesions (naevus junctionalis), compound lesions (naevus compositus) and ISSN 0023-2157 Index 362646 Surgical management of conjunctival nevi in children subepithelial lesions (naevus subdermalis) (1,4,8). The available sources do not describe any differences pertaining to management, prognosis and risk of neoplastic transformation based on the histological types of conjunctival nevi.…”

“…Early stages of conjunctival melanoma may be clinically indistinguishable from benign lesions. However, the analysis of large patient groups indicated that the estimated risk of conjunctival nevus transformation into melanoma is below 1% (1,3,8,9). Melanoma is a malignant neoplasm derived from melanocytes.…”