Brain abnormalities on MRI in non-functioning pituitary adenoma patients treated with or without postoperative radiotherapy.

Background And Purpose: To assess and compare brain abnormalities on Magnetic Resonance Imaging (MRI) in non-functioning pituitary macro-adenoma (NFA) patients treated with or without postoperative radiotherapy (RT).

Material And Methods: In 86 NFA patients, treated between 1987 and 2008 at the University Medical Center Groningen, white-matter lesions (WMLs), cerebral atrophy, brain infarctions and abnormalities of the temporal lobes and hippocampi were assessed on pre- and post-treatment MRI scans in patients treated with (n=47) or without RT.

Results: The median MRI follow-up time for RT patients was 10 (range 1-22) years and 5 (range 1-21) years in patients treated without RT. In RT patients the cumulative incidence of WMLs was significantly lower compared to patients treated without RT (log-rank test RR 0.49, 95% CI 0.25-0.97, p=.042). The cumulative incidences of cerebral atrophy, brain infarctions, abnormalities of the temporal lobes and hippocampi, and the severity of WMLs and cerebral atrophy ratings were not significantly different between the two treatment groups.

Conclusions: Brain abnormalities on MRI are not observed more frequently in NFA patients treated with RT compared to patients treated with surgery-alone. Furthermore, RT was not associated with an increased severity of WMLs and cerebral atrophy ratings in this cohort of NFA patients.