BACKGROUND: Pseudoepitheliomatous hyperplasia (PEH) is a rare, benign, rapidly growing proliferation of conjunctival or corneal epithelium that typically occurs due to chronic ocular inflammation. The clinical presentation of PEH greatly resembles ocular surface squamous neoplasia (OSSN), a malignant condition with the potential for intraocular invasion and metastasis that has been linked to chronic sun exposure and human papilloma virus infection. Differentiating these conditions can often be accomplished through histological analysis; dysplastic cells of the squamous epithelium are found in OSSN but absent in PEH. However the two conditions share other microscopic features including cellular atypia, acanthosis and hyperkeratosis.
CASE REPORT(S): A 72-year old white male presented to our clinic with a red, painless lesion on his right eye of six months duration. Slit lamp exam revealed a mass measuring 3 x 3 x 2 mm at the temporal limbus. The lesion demonstrated both papillomatous and leukoplakic characteristics, and it was surrounded by dilated conjunctival feeder vessels. Due to the suspicious nature of the lesion the patient was referred to an anterior segment specialist where excisional biopsy and cryotherapy were performed. The initial pathology report found chronic inflammation and reactive atypia but no dysplasia. A second opinion was requested to confirm these findings. In the meantime topical Interferon alpha 2B drops were started as a prophylactic measure. When the second pathology report ruled out dysplasia, the Interferon drops were discontinued.
CONCLUSIONS: Suspected ocular surface malignancies usually undergo excisional biopsy to confirm diagnosis, decrease the chance of invasion, and alleviate patient unrest. Histological analysis of biopsied tissue often yields equivocal results. PEH and OSSN represent two conditions that are similar clinically and histologically. In this case the absence of dysplasia rules out OSSN making PEH the best diagnosis. In uncertain cases adjunctive topical treatments may be utilized.