Factors associated with conjunctival intraepithelial neoplasia: a case control study.

Familial and environmental factors may play a role in the development of conjunctival intraepithelial neoplasia (CIN). Nineteen patients with biopsy-proven CIN completed a questionnaire to evaluate possible predisposing factors. Nineteen age-matched and sex-matched controls completed questionnaires and received slit-lamp examinations. Factors associated with a relatively increased risk of developing CIN included exposure to petroleum products, heavy cigarette smoking, light hair and ocular pigmentation, and family origin in the British Isles, Austria or Switzerland. Non-office and nonprofessional workers were more likely to develop conjunctival intraepithelial neoplasia (p = .05), as were those who were not college graduates (p = .07).