carcinoma is the second most common malignancy of the eyelid (basal
cell carcinoma is the most common malignant eyelid tumor).
carcinoma may spread into the conjunctiva and may generate the clinical
appearance of a blistering condition such as pemphigoid. Histologically,
intraepithelial sebaceous carcinoma in the conjunctiva may mimic
pemphigoid. Ophthalmologists should be particularly cautious in
making the diagnosis of unilateral pemphigoid (sebaceous carcinoma
is usually unilateral -- pemphigoid is usually bilateral!). As always,
ophthalmologists should be gentle in handling the tissue and prepare
the specimen properly for submission to the laboratory.
the diagnosis of sebaceous carcinoima is established in the eyelid,
the ophthalmologists may take non-directed conjunctival biopsies
to map the presence of conjunctival involvement by tumor.
should note that the appearance of sebaceous carcinoma in the conjunctiva
mimics squamous epithelial dysplasia or carcinoma in situ. Look
for foamy cytoplasm and smudged basophilic nuclei. Mitotic figures
may be abundant and are often atypical.
carcinoma involving the conjunctiva. This condition may mimic squamous
epithelial dysplasia or carcinoma in situ histologically.