Mast cells in an angiosarcoma complicating Xeroderma pigmentosum in a 13-year-old girl

A cutaneous angiosarcoma, a rare tumor that occurs almost exclusively in su n-exposed skin of individuals older than 50 years, developed in an adolesce nt with Xeroderma pigmentosum (XP). As this is the second report of a child with angiosarcoma and XP, ultraviolet-induced DNA damage may be involved i n the pathogenesis of this tumor Strongly increased numbers of mast cells w ere found, particularly in the peripheral tumor area, which may reflect wit h the requirement of mast cells for the growth of vascular structures or a role for mast cells in the antitumor immune response.