Peripheral Precocious Puberty as the Initial Manifestation of Juvenile Granulosa Cell Tumor in Early Childhood

Juvenile granulosa cell tumor (JGCT) is a rare ovarian sex cord-stromal tumor (SCST) occurring predominantly in children and adolescents.It is characterized by estrogen secretion, which often leads to peripheral precocious puberty and allows early clinical detection despite the tumor's rarity.We report the case of a previously healthy two-year-nine-month-old girl who presented with progressive breast development, persistent leukorrhea, and vaginal bleeding.Hormonal evaluation revealed suppressed luteinizing hormone and follicle-stimulating hormone concentrations associated with a markedly elevated inhibin B level (>5000 pg/mL), consistent with a hormonally active ovarian SCST.Contrast-enhanced computed tomography and pelvic magnetic resonance imaging demonstrated a large complex left ovarian mass with imaging features suggestive of malignancy.The patient underwent fertility-sparing left oophorectomy with comprehensive surgical staging.Histopathological examination and immunohistochemistry confirmed the diagnosis of JGCT, and the disease was classified as International Federation of Gynecology and Obstetrics stage IA.No adjuvant chemotherapy was administered, and the patient was managed with active surveillance.Hormonal abnormalities normalized within two months after surgery, and no evidence of recurrence was observed after 12 months of follow-up.This case highlights the importance of considering an estrogen-secreting ovarian tumor in very young girls presenting with peripheral precocious puberty.Early recognition of endocrine manifestations, combined with appropriate imaging, hormonal evaluation, and fertility-preserving surgery, enables excellent outcomes in localized disease.Inhibin B also represents a valuable individualized biomarker for postoperative surveillance when elevated at diagnosis.