The clinical, histological and immunohistochemical characteristics and nomenclature of meibomian gland ductal cysts (intratarsal keratinous cysts) and eyelid steatocystomas

Abstract

PurposeMeibomian gland ductal cysts (MGDCs) and steatocystomas are epithelial lined, keratin-containing lesions of the eyelids. MDGCs are variably called tarsal keratinous cysts, intratarsal keratinous cysts of the meibomian glands, intratarsal inclusion cysts, epidermal cysts and epidermoid cysts. Both lesions are poorly described in the literature. We report a series of seven MGDC and steatocystomas, and examine their clinical, pathological and immunohistochemistry features and their management and outcomes.Patients and methodsA retrospective review of case notes and histopathology slides of all MGDCs and steatocystomas identified at one major histopathology service in South Australia between 2013 and 2015.ResultsSeven cases were identified, with an average age of 64. The lesions range from 4 to 18 mm diameter and are firm, well-circumscribed and non-tender, and sometimes the keratin-filled cyst protrudes visibly under the tarsal conjunctiva. Two cases were previously misdiagnosed as chalazia but recurred after incision and curettage. Histologically, these lesions are lined by squamous epithelium but lack a well-formed stratum granulosum and can be distinguished by their immunohistochemical staining characteristics. Complete excision, including a wedge of underlying tarsal plate for MDGCs, is curative for with a follow up of 12-36 months.ConclusionsMGDCs and steatocystomas should be included in the differential of benign eyelid lesions. Diagnosing and differentiating these lesions from chalazia is important for determining the optimal management strategy.

Tarsal-related cysts: Different diagnoses with similar presentations

“…However, transcutaneous compared to transconjunctival approach in reported cases did not show any recurrence or cosmetic problem 7 . The use of an amniotic membrane patch graft after the excision of the conjunctival tarsus is an option to cover the defect 7 . An injection of cortisone into the cyst alone didn’t show a response in one case reported by Jordan et al 10 …”

“…Unlike chalazion that contains sebum and inflammatory materials, those cysts have the consistency of tofu residue like a milky fluid as described by Kim et al 2 They are characterized by strand-like keratinous materials within the cyst and lined by stratified squamous epithelium with eosinophilic cuticle 1, 7. Also, they lack the formed underlying stratum granulosum which is known for epidermoid cysts 8 …”

“…Conjunctival approach was suggested to be a better way for a complete excision of the lesion and to avoid a cosmetic problem 4 . However, transcutaneous compared to transconjunctival approach in reported cases did not show any recurrence or cosmetic problem 7 . The use of an amniotic membrane patch graft after the excision of the conjunctival tarsus is an option to cover the defect 7 .…”

Tarsal Epithelial Cysts: Prevalence, Case Series, and Synthesis of Existing Literature

“…Twelve case reports 1,2,4–13 and 6 case series were included. 3,14–18 The largest series outlined 15 cases of TEC. 14 The mean age of all patients was 52.3 years (range 18–85 years), with 50.8% being female.…”

“…TECs are much more common in the upper eyelid, possibly due to the higher number of meibomian glands compared to the lower eyelid. 10,16,18 They are embedded in or fixed to the tarsus but free from the overlying skin, unlike EICs and steatocystomas which are located in the dermis and therefore fixed to the skin. 16 Unlike sebaceous cell carcinoma, TEC generally do not cause loss of eyelid architecture, and madarosis is universally absent.…”