Endocrine Abstracts

Case report: Central neurocytomas are well-differentiated rare central nervous system tumours. These tumours when identified in brain parenchyma or spinal cord are termed as extra ventricular neurocytomas. We report a case of 40 year old lady with mild hypertension who presented with long standing history of intermittent headaches which got worse 2 months before presentation, mainly affecting her forehead and left retro-orbital region. She also noted blurring of vision in her left eye. She had long standing weight gain with menstrual irregularities. On physical examination, she had BMI of 50 but no other signs of growth hormone or cortisol excess. Visual fields on confrontation method revealed subtle bitemporal defects which were later confirmed on formal neuro visual fields test.

Investigations: Her pituitary function tests done before surgery showed non-functioning type with ACTH 19 ng/l (normal 0–46), TSH 1.9 Mu/l (normal 0.35–0.55), Prolactin 286 mu/l (normal: 59–619), IGF1:109 ng/ml (normal: 63.4–223.0), FT4 14.9 pmol/l (normal: 10–20), Cortisol 395 nmol/l (normal: 200–500). Both CT and MRI scans showed expanded pituitary gland with 18×29×23 mm sellar and suprasellar lesion with significant compression of optic chiasm which also appeared pre-fixed. Radiologically it was reported as macroadenoma.

Results and treatment: Her case was discussed in our Pituitary multidisciplinary team meeting.It was though thatgiven the size of lesion, there was high potential for significant supra-sellar remnant necessitating re-do surgery which was discussed with patient prior to proceeding for first surgery. She underwent trans-sphenoidal subtotal resection due to unusual shape of lesion. Histology confirmed WHO grade 2 extraventricular neurocytoma which was Chromogranin A, CD56 and Synaptophysin positive. There was no hormonal staining. Overall appearance was of pituitary neuronal tumour with no convincing accompanying adenomatous component. The Ki-67 labelling index was variable and focally elevated to around 1–6%. Post-surgical MRI after 3 months showed sizeable remnant with visual fields not fully recovered to normal. Genetic analysis has been requested, including AIP gene mutation. Her pituitary profile after surgery was normal. She is planned to have further pituitary surgery.

Conclusions and points for discussion: Our case highlights a challenging case of Pituitary extraventricular neurocytoma which presented as a macroadenoma with significant chiasmal compression and visual field defects. The outcome of re-do surgery remains to be seen. Since chemotherapy and radiotherapy is proven to have positive outcomes after surgery, a detailed MDT discussion will be important for further management plan.