Hormonal cluster #1 consisted primarily of NSGCT malignancies (12 to 16% of samples, mixed and teratoma subtypes) and were characterized by high expression of the pituitary hormones PRL and GNRH1, HSD17B2 coding for sex hormone-deactivating enzyme, and SRD5A1 coding for a testosterone—DHT converting enzyme. This evidence concerns the gene HSD17B2 and teratoma.