Histologic Changes in a Squamous Cell Carcinoma of Conjunctiva Refractive to Interferon-α2b

A 74-year-old man presented with a limbal mass (Fig 1A), found by incisional biopsy to be full-thickness conjunctival intraepithelial neoplasia (squamous cell carcinoma in situ) (Fig 1B, arrow). No significant inflammation was present at this stage. Despite 3 months of topical interferon α-2b therapy, the lesion enlarged (Fig 1C). The mass was surgically excised, and histopathology revealed progression to invasive squamous cell carcinoma with marked pleomorphism, numerous mitotic figures (Fig 1D, arrow), foreign body giant cells (Fig 1D, asterisk), and dyskeratosis.