A large seminoma occurring 20 years after diagnosis of complete androgen insensitivity syndrome: A case report.

Complete androgen insensitivity syndrome (AIS) is a rare X-linked disease with an estimated prevalence of 1 in 20,000 and is characterized by a 46,XY karyotype and a female external phenotype (Wisniewski et al., 2000). AIS is caused by mutations in the androgen receptor gene, located on chromosome Xq11-12, which results in impaired embryonic sexual differentiation. The risk of malignancy is considerably lower in complete AIS than in partial AIS or other intersex disorders and occurs at a later age (Cheikhelard et al., 2008). Morris reported a 22% incidence of malignant gonadal tumors in patients over 30 years of age (Morris, 1953); however, because 50% of the patients studied had already undergone a previous gonadectomy, the risk of malignancy was underestimated. Current recommendations for patients with AIS suggest that cryptorchid testes be retained through puberty in order to receive the benefits from their hormone production, enhance bone maturation, and allow completion of secondary sexual development (Alvarez et al., 2005). Currently, limited data is available on individuals who have not had their testes removed (Deans et al., 2012). We report a case of a seminoma that developed in the testes 20 years after diagnosis of AIS.