Endocrine Abstracts

Introduction

Meningiomas and pituitary tumours are two most prevalent benign tumours of the CNS but neither are common and without a history of radiotherapy their concomitant existence is extremely rare. Meningiomas comprise 15–25% of all intracranial neoplasms while prevalence of benign pituitary adenomas is 10–23%. We report a rare case of co-existing Brain tumours.

Case

51 year old lady presented with deteriorating vision in left eye with deteriorating visual acuity. No other significant medical or family history. Examination revealed significant right hemianopia. The CT scan showed a suprasellar tumor of 32×31×13 mm. Short synacthen test and pituitary hormones were all normal. IGF-1 Prolactin 605 mIU/l. MRI suggested it to be a meningioma rather than a primary pituitary tumour which was confirmed by histopathology obtained by Transfrontal Debulking surgery followed by Radiotherapy for residual disease which she tolerated really well. Few months later she complained of some headaches, some weight gain, secondary amenorrhoea & galactorrhoea. Blood test for prolactin, LH, FSH, Oestradiol, TFTs, IGF1 and Cortisol was arranged and showed Prolactin 2225 mIU/l and normal other hormones. MRI was difficult to interpret due to recent surgery but showed no interval change from previously and she was started on Cabergoline following which her symptoms improved.

Conclusion

In our case the cause of rise in prolactin level post-surgery was unclear. Radiation induced hypopituitarism could be one of the causes but the fact that all other pituitary hormones were stable makes it less likely. A co-existing microprolactinoma is more likely. The diagnosis of co-existing brain tumours is not easy to make based only on MRI, but it is important to distinguish between them as the treatment strategy for these tumours are different. Post-surgical evaluation in cases of suprasellar meningiomas with regular monitoring of the pituitary function might be beneficial.