Tumors of the eye and adnexa in the Sudan.
854 lesions involving the eye and adnexa in the Sudan were studied as regards their frequency, sex and age incidence, site, pathologic types and geographic and racial distribution. Of 279 primary malignant tumors (frequency ratio 4.3%), conjunctival squamous carcinoma was the commonest (50.4%) while retinoblastoma formed 20.8%, basal cell carcinoma 6.1% and malignant melanoma 4.6%. Conjunctival carcinoma and allied epithelial lesions occurred much more predominently in Northern than in Southern Sudan and no basal cell carcinoma of the eyelids was recorded in the latter. Retinoblastoma and melanoma showed certain tribal predilections. Most cases of Burkitt's lymphoma occurred in Southern Sudan. It is concluded that geographic and racial factors play important roles in determining the frequency and pattern of eye neoplasms in the Sudan.