Promising Outcomes in Acromegaly Patients Receiving CyberKnife Stereotactic Hypofractionated Radiotherapy.

Area of Science:

• Endocrinology
• Neurosurgery
• Radiation Oncology

Background:

• Acromegaly treatment traditionally relies on surgery, with radiotherapy (RT) use declining due to pharmacotherapy (PT) advancements.
• Persistent acromegaly after surgery and PT necessitates novel therapeutic strategies.
• CyberKnife Stereotactic Hypofractionated Radiotherapy (CK-HFRT) is explored for persistent acromegaly.

Purpose of the Study:

• To evaluate the efficacy of CK-HFRT in achieving endocrine remission (ER) in persistent acromegaly.
• To assess the safety profile of CK-HFRT, focusing on toxicity.
• To determine tumor control and survival rates following CK-HFRT.

Main Methods:

• Retrospective analysis of 31 acromegaly patients treated with CK-HFRT after failed surgery and PT.
• Evaluation of various CK-HFRT dose fractionation regimens and dose volume histograms.
• Assessment of tumor control, ER, cured disease (CD) rates, overall survival, and toxicity (pituitary insufficiency, RION) at median 62-month follow-up.

Main Results:

• 100% tumor control (nonprogressive adenomas) observed at 62 months.
• High endocrine remission (ER) rate of 86.7% achieved, with a 22.4% cured disease (CD) rate at five years.
• 32.3% incidence of pituitary insufficiency; no radiation-induced optic neuropathy (RION) reported. Five-year overall survival was 79.2%.

Conclusions:

• CK-HFRT serves as a valuable adjunct to PT for persistent acromegaly post-surgery.
• The treatment demonstrates significant ER rates and tumor control with a favorable safety profile regarding optic nerve damage.
• Individualized patient assessment is crucial when considering CK-HFRT due to varying treatment histories and overall health conditions.