ESPE Abstracts

A 7 year old girl presented with breast development, mood changes and rapid growth spurt from 6.5 years. Clinically she was tall for her family and had Tanner stage 2 breast development and pubic hair. Bone age was 3 years advanced and pelvic ultrasound demonstrated globular anteverted uterus with endometrial lining and enlargement of the ovaries with follicles. LHRH test confirmed central precocious puberty with peak LH 44mIU/ml and FSH 19mIU/ml, with baseline estradiol of 92pmol/l. The pituitary function was otherwise normal. MRI pituitary demonstrated a 4x2mm hypodense lesion in the right side of the pituitary gland, with rim of enhancement suggestive of a pituitary adenoma. She was commenced on GnRH analogue treatment with good effect, with no further pubertal progression. Repeat MRI after 6 months did not show any interval change in the appearance of the adenoma. Repeat baseline pituitary function and tumour markers were normal aside from raised IGF1 +3SD. By age 9 there was pubertal progression with more breast enlargement, vaginal discharge and emotional lability. She had incomplete suppression of the LH and FSH, but unmeasurable estradiol. The IGF1 remained elevated and HCG was normal. The bone age was now 2.6 years advanced and the pelvic ultrasound confirmed further uterine and ovarian development. It became clear that she had received the previous GnRH analogue injection 4 weeks late due to travelling. The MRI was repeated and the same hypodense lesion was seen in the right side of the pituitary gland but this time the sagittal images were suggestive of a bony spur protruding into the pituitary gland and disrupting the pituitary shape with displacement of the posterior pituitary, which on coronal images was giving the appearance of a hypodense lesion with rim of enhancement. A CT brain showed the bony ‘thorn’ which was confirmed as a posterior sellar spine growth. A posterior sellar spine is a rare congenital finding, arising from ossification of the cephalic end of the notochord. They have been reported as asymptomatic incidental findings or in association with pituitary disease e.g. galactorrhoea, hypopituitarism, Cushing’s syndrome and amenorrhoea. There is one previous report in the literature of a posterior sellar spine with precocious puberty. On imaging the osseous spur is seen arising from the posterior sellar wall and extending into the pituitary fossa. They can be misdiagnosed as pituitary neoplasms, leading to further interventions, hence recognition and accurate diagnosis are critical.