Orbital amelanotic melanoma in xeroderma pigmentosum: a rare association.

Xeroderma pigmentosum (XP) is an autosomal recessive genetic disorder of DNA repair in which the body's normal ability to repair damage caused by ultraviolet light is deficient. This leads to a 1000-fold increased risk of cutaneous and ocular neoplasms. Ocular neoplasms occurring in XP in order of frequency are squamous cell carcinoma, basal cell carcinoma and melanoma. Malignant melanomas occur at an early age in patients with XP. We report a case of XP with massive orbital melanoma in an eight-year-old boy which is unique due to its amelanotic presentation confirmed histopathologically.