a) What s ocular surface squamous neoplasia?
Ocular surface squamous neoplasia is pre-cancerous or cancerous changes to the surface of the conjunctiva. Pre-cancerous changes can cause a condition called conjunctival intraepithelial neoplasia. This condition can turn into squamous cell carcinoma, which is a sinister tumour. This can spread onto the cornea causing decrease in vision. It usually affects one eye and is caused by sun damage.
b) What are the symptoms of ocular surface squamous neoplasia?
A fleshy pale lump is usually noticed on the surface of the eye next to the cornea. It may grow onto the cornea and, if large, can cause:
• Grittiness to the eye
• Blurring of vision
Sometimes it can grow form the conjunctiva onto the eye lid.
c) What are the risks of getting ocular surface squamous neoplasia?
Risk factors for this condition include:
• Sun damage
• Fair skin
• Older age
• Conditions decreasing the immune system (e.g. HIV)
d) Will I need any tests?
In the clinic we may take pictures of the front of the eye. It is difficult to tell apart conjunctival intraepithelial neoplasia (pre-cancerous) from squamous cell carcinoma (cancerous). If the abnormal area is removed with surgery then it is sent to the laboratory to help confirm the diagnosis.
e) What is the treatment for ocular surface squamous neoplasia?
The main treatment is surgery (surgical excision). We may, however, use freezing treatment (cryotherapy) and Mitomycin C (MMC) eye drops as well. MMC can, however, irritate the eye. To treat this we may provide you with lubricant or steroid eye drops.