Risk of new tumor, carotid stenosis, and stroke after stereotactic radiosurgery for pituitary tumor: a multicenter study of 2254 patients with imaging follow-up

Abstract

Background A higher risk of secondary brain tumor, carotid stenosis, and stroke has been reported after conventional sella irradiation for pituitary neuroendocrine tumors (PitNET). Stereotactic radiosurgery (SRS), which is a more focused approach, is now increasingly used instead. The aim was to assess the risk of secondary brain tumor, carotid stenosis/occlusion, and stroke after SRS.

Methods In this multicentric retrospective study, 2254 patients with PitNET were studied, 1377 in the exposed group, and 877 in the control group.

Results There were 9840.1 patient-years at risk for the SRS and 5266.5 for the control group. The 15-year cumulative probability of secondary intracranial tumor was 2.3% (95% CI: 0.5%, 4.1%) for SRS and 3.7% (95% CI: 0%, 8.7%) for the control group (P = .6), with an incidence rate of 1.32 per 1000 and 0.95 per 1000, respectively. SRS was not associated with an increased risk of tumorigenesis when stratified by age (HR: 1.59 [95% CI: 0.57, 4.47], Pp = .38). The 15-year probability of new carotid stenosis/occlusion was 0.9% (95% CI: 0.2, 1.6) in the SRS and 2% (95% CI: 0, 4.4) in the control group (P = .8). The 15-year probability of stroke was 2.6% (95% CI: 0.6%, 4.6%) in the SRS and 11.1% (95% CI: 6%, 15.9%) in the control group (P < .001). In Cox multivariate analysis stratified by age, SRS (HR 1.85 [95% CI:0.64, 5.35], P = .26) was not associated with risk of new stroke.

Conclusions No increased risk of long-term secondary brain tumor, new stenosis or occlusion, and stroke was demonstrated in the SRS group compared to the control in this study with imaging surveillance.