Giant Onychomatricoma of the Great Toenail: Case Report and Review Focusing on Less Common Variants

Abstract

Onychomatricoma is a rare benign fibroepithelial filamentous tumor originating from the nail matrix. It typically presents with the clinical tetrad of xanthonychia, pachyonychia, proximal splinter hemorrhages and increased transverse overcurvature of the nail plate. The giant variant can easily confuse the clinician due to its extensive nail dystrophy that can mask the characteristic features of this tumor. Benign (fibrokeratoma, ungual fibroma, onycholytic matricoma) and malignant entities (Bowen's disease, squamous cell carcinoma, onycholytic carcinoma) are mimics of the disease. Nail surgery can facilitate the diagnosis, which should always be confirmed by histology, as rare variants do exist.

Asymptomatic Longitudinal Pachyxanthonychia of the Fingernail

“…OM's fibroblastic stroma stains positively for CD34 and may show wreath-like multinucleated cells (pleomorphic OM) and mucinous changes (myxoid OM) [8]. Aside from lacking a stromal component, OCM has a relatively flattened and relatively thicker basal epithelium in contrast to the undulating thin basal compartment seen in the acanthothic epithelium of OM [3].…”

Onychomatricoma: A Rare Nail Tumor with an Unusual Clinical Presentation

“…Most of the reports on onychomatricoma present tumors found only in a portion of the nail plate, demonstrated by a superficial band-like pattern of yellowish discoloration with increased transverse curvature of the nail. To date there have been 5 reported cases of giant onychomatricoma (Table 1), all of them with a history of prior trauma [10,11,12,13]. Interestingly, all tumors were found to be located on the great toenail or thumbnail, which are areas that are potentially more susceptible to trauma.…”

Onychomatricoma with Onychomycosis: A Case Report and Review of the Literature

“…It was first described by Baran and Kint in 1992 [1]. Onychomatricoma is suspected clinically and radiologically, but histopathology is mandatory for confirming diagnosis [2,3]. Onychomycosis sometimes has similar clinical features and eventually leads to an initial misdiagnosis [4].…”