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

Purpose Tarsal epithelial cysts (TECs) are squamous epithelial-lined lesions of the eyelid that are often mistaken for chalazia or epidermal inclusion cysts. They remain poorly described in the literature. This study is designed to characterize the prevalence and clinical features of TEC. Methods We conducted a single-center retrospective review of adult patients with a diagnosis of eyelid neoplasm, eyelid cyst, hordeolum, stye, or chalazion between January 1, 2011 and July 1, 2017. Among this cohort, we identified patients with a histopathologic diagnosis of TEC. We also conducted a PubMed literature review and synthesis of existing clinical data of patients reported to have TEC, noting common clinical and histopathological features. Results Of 7,516 patients, we identified 6 patients with a histopathological diagnosis of TEC, amounting to a prevalence of 0.08% amongst patients with eyelid lesions. Average age was 49.7 years (range 18-76 years), with a 1:1 male to female ratio. The most common presenting symptom was a painless eyelid mass, and the majority (66.6%) had a preoperative diagnosis of chalazion. All but 1 patient had surgical excision from the posterior approach and there was 1 recurrence in the follow-up period. On review of the literature, we identified 68 prior cases of TEC from 18 clinical studies, with clinical features mirroring our case series. Conclusions TEC has stereotypical clinical and histologic features that distinguish it from other tarsal lesions. Our review identified TEC as a relatively rare cause of eyelid lesions.