GonadalTumorinFrasierSyndrome:AReviewand Classification

Frasier syndrome is a rare inherited disease characterized by steroid-resistant nephrotic syndrome, gonadal tumor, and male pseudohermaphroditism(femaleexternalgenitaliawithsexchromosomes XY), which is based on a splice site mutation of Wilms tumor-suppressor gene 1 (WT1). Several unusual Frasier syndrome cases have been reported in which male pseudohermaphroditismwasabsent.Wereviewed88Frasiersyndromecasesinthe literatureandclassifiedthemintothreetypes(type1–3)according to external genitalia and sex chromosomes, and described their clinical phenotypes. Type 1 Frasier syndrome is characterized by female external genitalia with 46,XY (n ¼ 72); type 2 by male external genitalia with 46,XY (n ¼ 8); and type 3 by female external genitalia with 46,XX (n ¼ 8). Clinical course differs markedly among the types. Although type 1 is noticed at the mean age of 16 due to mainly primary amenorrhea, type 2 and 3 do not present delayed secondary sex characteristics, making diagnosis difficult. The prevalence of gonadal tumor is high in type 1 (67%) and also found in 3 of the 8 type 2 cases, but not in