Squamous cell carcinoma of the conjunctiva

Introduction and epidemiology Squamous cell carcinoma of the conjunctiva is the end-stage of a spectrum of disease referred to as ocular surface squamous neoplasia (OSSN). OSSN is a malignant disease of the eyes that can lead to loss of vision and, in severe cases, death. The main risk factors for both are exposure to solar ultraviolet radiation outdoors, HIV/AIDS, human papilloma virus and allergic conjunctivitis. The limbal epithelial cells appear to be the progenitorsof this disease. OSSN is an important ophthalmic public health problem in equatorial Africa, where there are both high levels of UV radiation and a high incidence of HIV/AIDS. Africa has the highest incidence of OSSN in the world, affecting about 1.3 people per 100,000 population per year; so, if you work in an eye clinic serving a population of 1 million people, you could expect to see one case each month if they all came to the clinic.1 By contrast, the incidence in other regions is about 0.1 people per 100,000 population per year, over 10 times lower. Two disease patterns occur. In equatorial Africa, OSSN affects younger adults and proportionally more women than in other parts of the world. Recent studies in Kenya, for example, found that the mean age of OSSN patients is around 40 years, two-thirds are women and about three-quarters are living with HIV. Elsewhere, OSSN affects older adults (the mean age is about 60 years) and 70% are male.