[Precocious puberty in girls depending on choriogonadotropin - case reports and literature review].

A 5-year-old girl presented typical features of isosexual precocity with breast and pubic hair development (Tanner stage 3) and menarche, following a few months history of hirsutism of the back and thighs. Stimulation testing revealed GnRH-independent precocious puberty, secondary hypothyroidism, hyperprolactinemia and mild testosteronemia. The ovaries in ultrasound examination were prepubertal. Tumor markers beta-HCG and AFP were markedly elevated and a suprasellar germ cell tumor 25x15 mm in size was visualized by MRI. Combined chemotherapy followed by radiotherapy resulted in normalization of pubertal features along with estrogen and marker levels. These data indicate a possible development of precocious puberty in girls induced by choriogonadotropin (hCG) released by a supracellar germ cell tumor. Based on our observations and the literature on the subject the authors believe that the autonomous presence of aromatase inside the tumor may be responsible for precocious puberty in girls with hCG-releasing germ cell tumors, regardless of their location. In such cases the rare character of isosexual precocious puberty in girls may result from a unique combination of high hCG-releasing activity and high aromatase activity. In girls with precocious puberty, when discrete androgenization signs develop, the authors postulate to extend the diagnostic management so that hCG-dependent precocious puberty could be ruled out.