Background: Feminising preocious pseudo-puberty in McCune Albright syndrome (MAS) and juvenile granulosa cell tumour (JGCT) arises from bilateral and unilateral estradiol hypersecretion respectively. GNAS mutations have been described in some cases of JGCT as well causing MAS.
Aim: To describe a case in which MAS was evoked initially, but then progressed to JGCT
Case: A girl aged 2 years and 2 months, with no relevant family history, was admitted for premature sexual development. Her height was +2.6 SD, midparental height -0.4 SD, Tanner stage B3P2A1, bone age 5 yrs. Skin examination showed a single café au lait patch, 3cm in its largest axis, with irregular outline situated on the antero-lateral border of the left thigh. No other significant findings on examination were found including no bony lesion. LHRH test showed basal/peak LH 0.43/0.18 mUI/ml, FSH < 0.1 mUI/ml. Pelvic ultrasound showed an enlarged left ovary (63mm in longitudinal axis) and with multiple cysts (largest 38 mm). The right ovary was enlarged too (66mm in longitudinal axis) with multiple cysts (largest 38 mm).
MAS was considered likely and Tamoxifen 20 mg daily started. After only 7 weeks, there was a rapid increase in height and breast development to B3-4, with menorrhagia, bone age now 6.5 yrs. A second LHRH test showed gonadotrophin suppression. Pelvic ultrasound now showed a left-sided vascular solid/cystic ovarian tumour measuring 10x8x6 cm, with normal right ovary. Within a week, the tumour underwent torsion and was removed. The tumour weight was 850g, histopathology showed a juvenile granulosa cell tumour FIGO stage IA, mutational analysis for GNAS was negative.
Discussion: The aetiology in this case remains unclear, with MAS unproven, and evolution towards JGCT. Studies to determine AKT1 mutation in the tumour are planned. This case highlights current uncertainties in the causes of ovarian precocious pseudopuberty and the relationship between MAS and JGCT.
19 - 21 Sep 2019
European Society for Paediatric Endocrinology