Gonadoblastomas in 5 patients with 46,XY gonadal dysgenesis.

We describe five patients with 46,XY gonadal dysgenesis who developed gonadoblastomas, dysgerminomas, a mature teratoma, and a testicular intraepithelial neoplasia. The age of the patients was between 12.2 and 18.5 years. The external genitalia were normal female in two cases, in three they were intersexual. Four of our patients presented with slight retardation of puberty followed by stagnation. Most importantly the development of the breast (Tanner stage 2-4) did not correspond with pubic hair stage (Tanner stage 4). The patients can be classified as virilized phenotypical females. Serum testosterone was detectable in three, estradiol in two patients. None of the gonadoblastomas showed immunoreactivity with antibodies against steroid hormone receptors and against testosterone and estradiol, respectively. Probably the immature cells are able to produce steroid hormones. Only steroid-like cells with Leydig cell appearance showed positive cytoplasmatic immunostaining for testosterone in three patients. The findings in our patients underline that dysgenetic gonads must be removed as early as possible to prevent development of malignant tumors.