Ocular surface squamous neoplasia among HIV-infected patients in Botswana.

BACKGROUND Ocular surface squamous neoplasia (OSSN) is a group of ocular tumours that has been rising in incidence among HIV-infected individuals in sub-Saharan Africa. Surgical excision is the mainstay of treatment for OSSN in this region. METHODS This retrospective cohort study examined the clinical characteristics and treatment modalities used for 468 patients with OSSN from a large tertiary referral center in Gaborone, Botswana, over a 10-year period from 1998 to 2008. RESULTS The estimated annual incidence of OSSN in Botswana reached a peak of 7.0 cases per 100 000 persons per year in 2004. The mean age of the patients in the study was 38 years (interquartile range 30 - 44), and 53.9% were women. Of the patients, 48.5% were known to be HIV-infected, 1.5% were HIV-uninfected, and 50.0% had unknown HIV status. Among HIV-infected patients with CD4 counts, the median CD4 count was 192 cells/µL. As initial OSSN treatment, 20.7% of patients received simple surgical excision, 70.9% received surgical excision with adjunctive beta radiation, 0.9% received evisceration, 1.3% received enucleation, and 6.2% underwent surgical removal of unknown type. The overall rate of known recurrence was 7.1%; however, among those with at least 6 months of follow-up, the recurrence rate was 24.2%. Rates of known recurrence after simple surgical excision and surgical excision with adjunctive beta-radiation were 10.3% and 5.4%, respectively. CONCLUSION This study confirms the high incidence of OSSN among young individuals in Botswana. Further investigation is warranted to determine the most effective treatment modalities to prevent recurrence of OSSN among patients in sub-Saharan Africa.