Even though ocular surface squamous neoplasia (OSSN) has been recognized for well over a century, the past decade has witnessed advances that have helped rewrite many of the paradigms for the diagnosis and management of these lesions. OSSN occurs predominantly in the elderly for whom they are the third most common oculoorbital tumors after melanoma and lymphoma. In addition to advanced age and male sex, other major risk factors linked to its pathogenesis are ultraviolet light, cigarette smoking, and the human papilloma virus. Although the latter has been linked to OSSN for nearly 4 decades, its identification and role in the pathogenesis of these tumors has been elucidated recently and is addressed in detail in this review. Newer techniques of impression cytology represent a noninvasive and reliable method of diagnosing OSSN and monitoring treated cases. The efficacy of chemotherapeutic agents such as mitomycin C and 5-fluorouracil have been proven in the recent past, making them a clear alternative to the time-tested treatment of surgical excision and cryotherapy. Early reports on the efficacy of topical Iterferon α 2b indicate significant promise in providing another alternative for the treatment of some of these neoplasms. These advances thus represent a minimally invasive and highly successful approach to the diagnosis and treatment of OSSN.
Squamous lesions of the cornea and conjunctiva are uncommon but important because of their potential for causing ocular and even systemic morbidity and mortality. The clinical presentation of these lesions extends across a wide spectrum and differs based on the degree of pathologic involvement. The latter can range from mild to severe dysplasia to full-thickness epithelial dysplasia (carcinoma in situ) and invasive squamous cell carcinoma. Squamous neoplasms can involve the conjunctiva or the cornea individually but more commonly start in the conjunctiva and extend across the limbus to involve the adjacent cornea. Even though such lesions have been extensively reported since the first case described in 1860 by von Graefe, 1 the understanding of the pathogenesis and the management of these lesions has changed significantly in the past decade. In this paper, we review the recent advances and present the current status of the diagnosis and management of squamous neoplasms of the cornea and conjunctiva.