73-year-old male presented to urgent care with a few day history of foreign body sensation in his right eye
Previous ocular history remarkable for “no-touch technique” excision with cryotherapy OD and exenteration OS one year prior to current presentation for squamous cell carcinoma invasive to the orbit OS
Benign hereditary intraepithelial dyskeratosis
Conjunctival and corneal intraepithelial neoplasia (CIN)
Graded as mild, moderate or severe based on thickness involvement (partial vs full)
Squamous cell carcinoma
Excisional biopsies at initial visits, during exenteration and at recurrence one year later
Ocular surface squamous neoplasia (OSSN), which is an encompassing term for precancerous and cancerous epithelial lesions of the conjunctiva and cornea. It includes the spectrum of dysplasia, CIN and invasive squamous cell carcinoma.
Staging is dependent on biopsy as outlined by the 8th edition of the American Joint Committee on Cancer
Factors associated with the development of OSSN are:
Exposure to sunlight
HPV type 16 infections
Systemic associations of the development of OSSN include xeroderma pigmentosum
The nasal limbal area may be particularly vulnerable to solar UV radiation and has a high concentration of stem cells in the basal epithelium
Paradigms as detailed below consist of drop therapy vs surgical excision
Prognosis and Future Directions
Patient “no-touch technique” dissection with cryotherapy of new lesion of the right eye
POD1 BCVA 20/40 OD with sclera and conjunctiva amniotic membrane in place with vicryl sutures over conjunctival excision
Mutant TTN could be a potential prognostic biomarker for OSSN response to IFNα-2b treatment
The advent of next generation sequencing has started to provide insight into the genetic players that may drive treatment paradigms:
Usai Y, et al.Bilateral ocular surface squamous neoplasia: a clinicopathological case report. Br J Ophthalmol. 2004; 88:595-596.
Giuchuhi S, et al. Pathophysiology of ocular surface squamous neoplasia. Exp Eye Res. 2014 Dec;129:172-182.