Juvenile Granulosa Cell Tumor as the Presenting Feature of McCune-Albright Syndrome

Introduction GNAS mutations have been reprted in both McCune-Albright Syndrome (MAS) and juvenile granulosa cell tumors (JGCT), but have never been reported simultaneously in the same patient. Case Presentation A 15-year-old girl developed secondary oligomenorrhea. Laboratory studies revealed suppressed gonadotropin levels with markedly elevated estradiol and inhibin B levels. Pelvic ultrasound showed a 12-cm heterogeneous right adnexal mass; pelvic MRI to further characterize the mass displayed heterogeneous bilateral femoral bone lesions initially concerning for metastatic disease. PET/CT showed minimal fluorodeoxyglucose (FDG) uptake in the pelvic mass, but unexpectedly revealed FDG uptake throughout the skeleton, concerning for polyostotic fibrous dysplasia in the context of McCune-Albright Syndrome (MAS). The adnexal mass was excised and pathology confirmed a juvenile granulosa cell tumor (JGCT). The patient’s affected bone and JGCT tissue revealed the same pathogenic GNAS p.R201C mutation, while her peripheral blood contained wild type arginine at codon 201. Conclusion This mutation has been previously reported in cases of MAS and JGCT, but never simultaneously in the same patient. This demonstration of a GNAS mutation underlying both JGCT and MAS in the same patient raises questions about appropriate surveillance for patients with these conditions.

Tumor de células de la granulosa juvenil de ovario. Presentación inusual. Reporte de un caso

Granulose cell tumors represent 2% of ovarian tumors. They are classified as adult type and juvenile type. The juvenile type is associated with precocious pseudopuberty, irregular menstruation or nonspecific symptoms such as abdominal pain and palpable mass. More than 95% are confined to the ovary. A case of a 31-year-old patient is described. The patient consulted for 6-month evolution of increased abdominal volume and weight loss. Right ovary tumor was diagnosed. Tumor excision by gynecological laparotomy with positive frozen cut biopsy and surgical staging were performed. Pathological anatomy reported stromal tumor, and sexual cords suggestive of malignant juvenile granulose cell tumor. Immunohistochemistry reported positive inhibin B. It was concluded as stage IIIA2. This is a rare neoplasm with variable behavior. Accurate diagnosis is based on histological and immunohistochemical studies. Key words: Granulosa, Cell tumor, Juvenile granulosa cell tumor, Ascites, Diagnosis.