The deception of acantholysis: The painful and overlooked story of ocular surface squamous neoplasia in a red eye

A painful red eye can be extremely distressing and can be caused by various ophthalmological or dermatological disorders. We hereby report a case of a red, painful eye in a 55-year-old woman suspected to have pemphigus or ocular cicatricial pemphigoid. Acantholytic cells were seen on conjunctival biopsy, and treatment with prednisolone 60 mg/day with the preliminary diagnosis of ocular pemphigus showed no improvement. Reevaluation of the tissue block showed full-thickness dysplasia within the conjunctival epithelium and acantholytic cells. A diffuse subtype of ocular surface squamous neoplasia, formerly called Bowen’s disease of the eye, is an extremely rare condition and is often misdiagnosed as conjunctivitis, leading to delayed diagnosis. Our case posed an additional diagnostic dilemma due to the uncertainty caused by acantholysis in histology. She was finally treated with external beam radiotherapy, showing resolution of redness and pain. There was no recurrence over the next 1 year.