Pituitary adenomas are benign lesions comprising 10-15% of all intracranial tumours. Approximately 25% of all pituitary adenomas are clinically nonfunctioning (NFA). An incidence of 10 cases per million per year of NFAs is estimated1. Most patients present with symptoms at middle age, because of slow growth and absence of symptoms of hormonal hypersecretion2. This explains why NFAs are frequently macroadenomas with extension outside the sellar region.
As NFAs usually present with signs resulting from local mass effect, such as bitemporal hemianopsia, decreased visual acuity, and hypopituitarism, whereas patients quality of life may be impaired.
In contrast to other pituitary adenomas such as prolactinoma and growth hormone secreting adenomas, NFAs in general do not respond well to medical treatment3. Therefore, the treatment of choice is either transsphenoidal or transcranial surgery, aiming at complete tumour removal or decompression of surrounding structures only. Because of the invasive character of larger pituitary adenomas, with infiltration of the neighbouring structures such as arachnoid membrane, dura, sinus cavernosus and the skull base, complete surgical removal is frequently not achieved4.
Recent studies show a higher progression free survival rate for surgery plus adjuvant radiotherapy compared to surgery alone in patients with residual postoperative NFA5,6.
More frequent anterior pituitary dysfunction7, radiation optic neuropathy8, cerebrovascular disease9–13, and the induction of secondary tumors14,15 are proposed to be adverse sequelae of radiotherapy.
This cohort study was initiated to evaluate the role of radiotherapy on local control in perspective to the need for hormonal substitution therapy, other potential side effects, and life expectancy in patients with NFAs.