Increased incidence of retroperitoneal teratomas and decreased incidence of sacrococcygeal teratomas in infants with Down syndrome.

Individuals with Down syndrome (DS) have a unique profile of neoplasms, with a higher incidence of leukemias and a lower incidence of solid tumors than seen in the general population. We recently encountered two cases of infants with DS with retroperitoneal teratoma. After reviewing the literature on teratomas in DS, we found that the incidence of retroperitoneal teratomas was higher and the incidence of sacrococcygeal teratomas was lower in infants with DS than in the general population.