Hypofractionated stereotactic radiosurgery for pituitary metastases

Area of Science:

• Neuro-oncology
• Radiation Oncology
• Endocrinology

Background:

• Pituitary metastases (PMs) are rare, accounting for 1% of pituitary lesions.
• Diagnosis and optimal management of PMs remain challenging.
• PMs often present with endocrine and visual dysfunctions.

Purpose of the Study:

• To evaluate the efficacy and safety of hypofractionated stereotactic radiosurgery (SRS) for treating PMs.
• To assess tumor control and functional outcomes after SRS in PMs patients.

Main Methods:

• A pilot study involving seven patients with PMs (lung or breast origin) treated with hypofractionated SRS.
• SRS delivered a cumulative marginal dose of 31 Gy in 5 daily fractions.
• Optimized dosimetric planning with constraints for the optic apparatus.

Main Results:

• Complete tumor local control was achieved in all patients.
• Significant MRI response, including complete remission in 4 patients.
• Improvement in diabetes insipidus and visual dysfunction in all patients; anterior pituitary function did not recover.
• Median survival of 14 months post-SRS.
• No deterioration in visual, pituitary, or cranial nerve functions.

Conclusions:

• Hypofractionated SRS is a promising treatment for PMs, offering effective tumor control.
• SRS demonstrates significant functional benefits, particularly for diabetes insipidus and visual deficits.
• The safety profile is favorable, with no adverse neurological events reported.