Stereotactic radiosurgery in pituitary metastases: a systematic review and meta-analysis

The pituitary gland is an infrequent site for metastasis, encompassing approximately 0.4% of all intracranial metastatic lesions. The prognosis of pituitary metastasis (PM) remains dismal despite considerable advances in therapeutic interventions. Stereotactic radiosurgery (SRS) has been increasingly utilized as a minimally invasive therapeutic option for PMs. This study evaluated the efficacy and safety of SRS in patients with PMs.

On November 26, 2024, a systematic search was conducted through PubMed, Embase, Scopus, and Web of Science. Studies that have evaluated the role of SRS in PMs or PMs with cavernous sinus invasion were included. The meta-analysis, sensitivity analysis, publication bias evaluation, and meta-regression were conducted using the R program.

Seven studies with 79 individuals with PMs were included. The results showed a pooled local control (LC) rate of 92% (95%CI:83-98%) following intervention. The analysis resulted in a pooled diabetes insipidus (DI) improvement rate of 42% (95%CI:0-100%) and cranial nerve (CN) dysfunction improvement rate of 77% (95%CI:49-98%). In contrast, none of the patients with anterior pituitary dysfunction experienced improvement. The meta-analysis revealed a pooled ARE rate of 2% (95%CI:0-7%) with low heterogeneity (I² = 0%, P = 0.93). The subgroup analysis for single-session SRS revealed a pooled LC rate of 90% (95%CI:80-98%) and a pooled ARE rate of 2% (95%CI:0-8%).

SRS is correlated with promising improvement in LC, OS, and CN dysfunction in patients with PM. On the other hand, SRS is accompanied by limited effectiveness in DI and improvement in anterior pituitary dysfunction due to irreversible damage to the pituitary cells by metastatic lesions.