1. Consider surgery first
This is what Dr. Colby still considers the gold standard. It also enables the surgeon to provide a definitive diagnosis. This can be useful for tumors of different types that can have a similar appearance.
2. Weigh the pros and cons of chemotherapy
Topical chemotherapy, which is not approved by the FDA, treats the entire ocular surface.
“We know ocular surface squamous neoplasia [OSSN] results from sun exposure,” she said. “It makes sense that the whole surface of the exposed conjunctiva is at risk.”
Another advantage is it avoids the risk of scarring and infection that can occur with surgery. Topical chemotherapy works well in some patients, and overall, it is less expensive for the health-care system.
However, she adds that response to topical chemotherapy can be slow (taking months for lesion resolution) and does not provide a tissue-based diagnosis.
Many times, insurers--who tend to balk because it is not FDA approved—do not approve it.
“I have very poor luck in getting topical chemotherapy approved despite my pleading with them,” Dr. Colby said.
Literature reports show that interferon can be used topically or subconjunctivally with success for OSSN at 1 million units per cc. It also can reduce recurrence in the setting of topical margins, Dr. Colby said.
For now, there are no prospective, randomized trials to determine definitively if surgery or topical interferon treatment is better for OSSN, she added.