Balloon cell nevi of the conjunctiva: Clinicopathologic correlation and literature review

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.

Conjunctival Balloon Cell Nevus in a Young Child: A Case Report

Background:

Conjunctival balloon cell nevus is rare and often presents in young adults to middle-aged patients with a longstanding history of melanocytic lesion, suggestive of benign pathology. The main treatment modality is excisional biopsy. Tumor recurrence is very rare. Malignant transformation has never been reported.

Objective:

This study aimed to report a case of conjunctival balloon cell nevus with an atypical presentation in a preschooler.

Methods:

We describe a case of a 5-year-and-9-month-old girl who presented with a rapidly growing melanocytic conjunctival mass, which she had since birth. Ophthalmic examination showed two prominent feeder vessels, and the lesion straddled the limbus to overlie the peripheral part of the cornea. These findings raised an index of suspicion of malignant transformation. The lesion was completely excised with a 2-mm resection margin, superficial keratectomy, ethyl alcohol epitheliectomy, and cryotherapy.

Results and Discussion:

The histopathological examination and immunohistochemical study showed a compound conjunctival nevus of the conjunctiva with most of the cells as balloon cell type. There were no malignant changes found. Moreover, there were no signs of tumor recurrence at the last follow-up of 6 months.

Conclusion:

Clinically malignant characteristics have never been reported in balloon cell nevi in a preschooler of this age. Thorough physical examination, well-planned surgical procedure, and careful pathological examination all play vital roles in the management of patients with these lesions.

Dermoscopy and reflectance confocal microscopy of balloon cell nevi: a series of 10 cases

BACKGROUND

Balloon cell nevus (BCN) is a rare histopathological entity. It is usually represented by an asymptomatic brown smooth or polypoid lesion, but no clinical features allow differentiation from other melanocytic nevi. Moreover, dermoscopy and reflectance confocal microscopy (RCM) aspects of BCN have been described in a few single cases. This study aims to describe a wider BCN series with dermoscopic and RCM features to assess the most frequent patterns.

METHODS

Ten patients who underwent a BCN surgical excision with histological diagnosis were included in this study. Dermatoscopy and RCM were performed for each lesion, searching for the features described in literature.

RESULTS

Each nevus presented as an asymptomatic, smooth brownish lesion. Regarding dermoscopy, four balloon cell nevi showed yellow globules, eight white globules, eight a light-brown network at the periphery, and eight a structureless central area; moreover, we found a hyperpigmented central blotch in four cases. RCM examination highlighted aggregates of dense nests at superficial dermis level in all BCNs, characterized by the presence of a dark nucleus surrounded by vacuolized cytoplasm. Moreover, multiple melanophages were seen at the dermal-epidermal junction in one case and superficial epidermal dendritic cells in one case.

CONCLUSIONS

This series of 10 BCNs improves the dermoscopic and confocal microscopic knowledge of this rare entity. We also reported a new dermoscopic aspect represented by central hyperpigmented blotch. A correct identification of BCN with noninvasive techniques allows to avoid unnecessary surgical excision.

Conjunctival Melanocytic Nevi With Granular Cell Change

CONTEXT.—

Granular cell change in melanocytic nevus is underrepresented in the literature with only 4 well-documented cases, 1 described in the conjunctiva. Unfamiliarity with the clinical and pathologic features of these lesions contributes to the diagnostic difficulty.

OBJECTIVE.—

To delineate the clinical and histopathologic features of conjunctival nevi with granular cell change.

DESIGN.—

In a retrospective observational case series, the medical records of all patients with conjunctival nevi and granular cell change diagnosed between December 2016 and October 2018 were reviewed. Data collected included age, sex, clinical presentation, pathologic findings, and follow-up.

RESULTS.—

Twelve patients, 6 males and 6 females, with a median age of 14 years (range, 8-82 years) were identified. The nevus manifested as a pigmented, well-circumscribed nodule (7 of 9; 78%) or patch (2 of 9; 22%) in the bulbar and limbal conjunctiva (7 of 9; 78%) or in the plica semilunaris/caruncle (2 of 9; 22%). Cysts were noted in 7 of 9 lesions (78%). Features prompting surgical excision included atypical pigmentation (8 of 9; 89%), growth (7 of 9; 78%), and atypical vascularity (4 of 9; 44%). Microscopically, all lesions comprised a conventional melanocytic nevus with focal granular cell change and immunoreactivity for Melan-A, SOX10, and HMB-45, with Ki-67 proliferative index of less than 2%. Of the 9 lesions with follow-up information, there were no recurrences over mean follow-up of 11.2 months (range, 1-23 months).

CONCLUSIONS.—

Granular cell change in melanocytic nevi is an underrecognized finding that can simulate melanoma clinically and histopathologically. Young age at diagnosis, lack of associated conjunctival melanosis, bulbar location, cysts, and the absence of mitotic figures with a low Ki-67 proliferative index are helpful clinical and pathologic diagnostic clues.