Basaloid Follicular Hamartoma of the Eyelid

Abstract

An 86-year-old woman slowly developed a solitary 0.3 3 0.2-cm papule on the left lower eyelid. Complete excision disclosed a honeycombed lesion composed of interlacing basaloid strands unattached to the epidermis but rather extending into the dermis from a dilated hair follicle. The diagnosis was a solitary basaloid follicular hamartoma that can also occur in multiple, generalized, and inherited forms, sometimes with an associated systemic disease. The lesion exhibited a distinctive CD34-positive, mildly cellular myxoid stroma with many CK20-positive Merkel cells scattered within the basaloid cellular strands, which exhibited BCL-2 positivity only within the outermost cells bordering the stroma. These immunohistochemical features are the opposite of those displayed by basal cell carcinomas, which require more aggressive surgical management. Besides basal cell carcinomas, the differential diagnosis of basaloid follicular hamartoma includes fibrofolliculoma, tumor of the follicular infundibulum, poroma, and trabecular (Merkel cell) carcinoma.

Ongewone presentatie van een mesenchymaal ooglidhamartoma en een overzicht van het voorkomen van perioculaire hamartomen bij de hond

“…In human medicine, most hamartomas are described in newborns or infants. However, eyelid hamartomas have been described in adults without history of con-genital abnormality (Harris et al, 2008;Jakobiec et al, 2012). All dogs in the present case series were middle-aged to older dogs.…”

“…In the human-based literature, hamartomas have been described as a single-eyelid or conjunctival hamartoma without other ocular lesions or as part of a clinical syndrome. Reported solitary hamartomas of the eyelid include rhabdomyomatous mesenchymal hamartoma (Read et al, 2001), fibrous hamartoma (Bradfield et al, 2007), pigmented hamartoma with apocrine, follicular and sebaceous differentiation (Proia, 2007), striated muscle hamartoma (Harris et al, 2008), congenital smooth muscle hamartoma (Johnson and Jacobs, 1989), and basaloid follicular hamartoma (Jakobiec et al, 2012). Congenital smooth muscle hamartomas of the conjunctiva have been rarely reported in human medicine (Roper et al, 1999;Mora et al, 2012).…”

Basaloid follicular hamartoma of the eyelid in a pediatric patient

“…1 There are two prior reported cases of upper eyelid BFH in adults. 8 , 9 While they are considered benign, BFH may resemble basal cell carcinomas and rare cases of malignant transformation have been documented. 2 Additionally, they are often associated with congenital syndromes, myasthenia gravis, systemic lupus erythematosus, alopecia, and Graves’ Disease.…”

Basaloid Follicular Hamartoma of the Eyelid: A Case Report and Literature Review about an Unusual Lesion in the Ocular Region

“…Clinically, BFH can present as a small individual skin-coloured to brown papule, or as multiple lesions located mainly in the face, scalp or trunk [ 1 ]. Interestingly, only three cases of BFH were previously reported in the eyelid [ 4 , 5 , 6 ]. Histologically, BFH is characterized by an epithelial proliferation of basaloid cells which can mimic benign hair follicle-based lesions or basal cell carcinoma (BCC), among other entities [ 1 ].…”