Predictors of outcomes in non-functioning pituitary adenomas and neuroophthalmic and endocrine outcomes following pituitary apoplexy

Non-functioning pituitary adenomas are frequently associated with recurrence after primary treatment despite their benign status. Patients frequently require multiple treatments including a combination of surgery and pituitary radiotherapy. These treatments, in addition to the tumour, increase the risk of hypopituitarism which is known to be associated with increased mortality. Currently there is a lack of consensus of reliable predictors of recurrence in patients with NFPA. Historically many tumours have not been immunohistochemically stained for pituitary hormones which has resulted in the tumour being erroneously labelled as a null cell tumour which has been reported to be at increased risk of recurrence. The development of reliable assays to perform staining on tumour samples for transcription factors has been suggested to reduce the frequency ofdiagnosis oftrue immunonegative tumours.

We performed a retrospective analysis of patients with surgically managed NFPA to assess whether the addition of transcription factor staining and markers of proliferation provides further information to aid in assessing risk of recurrence. We compared differences in outcomes between tumour sub-types. In addition to this we assessed outcomes in patients presenting with pituitary apoplexy. 

We demonstrated that the addition of transcription factors reclassified 62.9% of samples tested which had previously been labelled as null cell.The rate of recurrence in patients with immunonegative tumours significantly reduced when adding transcription factor staining to pituitary hormone staining. We have shown that tumours with SF-1 expression appear to behave differently dependent on expression of LH/FSH. Tumours which lack LH/FSH staining but which stain positively for SF-1 were more likely to require repeated intervention. 

Pituitary apoplexy is rare however it is predominantly a condition seen in patients with NFPA. We have shown that in selected patients conservative management can be used without deterioration in outcomes however there is a spectrum of clinical presentation. Long-term endocrine dysfunction and visual sequelae are common regardless of management type.