Radiosurgical Hypophysectomy for Bone Metasteses Pain

A Pilot Study of Stereotactic Radiosurgical Hypophysectomy for Intractable Pain From Bone Metastases

This research is being done to see if a delivery of a single high dose of radiation therapy to a small area of the pituitary gland and pituitary stalk in a highly precise manner may be helpful in reducing intractable pain from bone metastases.

Although not currently standard of care, small series suggest both safety and efficacy of radiosurgical hypophysectomy in reducing cancer pain from bone metastases. In spite of the demonstrated feasibility in meeting normal tissue constraints and preliminary data suggestive of both safety and efficacy, radiosurgical hypophysectomy is rarely performed in clinical practice, and many radiation oncologists are not even aware of its potential to reduce intractable cancer pain. This is likely because, to date, well-designed prospective studies have not been performed to further explore both the safety and efficacy of the intervention. This single arm pilot study is designed to fill that void. If successful, the investigators plan to utilize the data to support the proposal of a larger scale follow-up clinical trial.

Inclusion Criteria:

1. Cytologic proof of malignancy
2. Radiographic evidence of bone metastases
3. Intractable pain uncontrolled by opioids, medical management, injections/ablation or surgical intervention that would be difficult to address with conventional radiation therapy or other standard options and is limiting the patient's function and quality of life. Intractable pain will be defined as a visual analogue score of at least 4.
4. Definitive radiographic progression of osseous and/or visceral metastases on standard staging scans (CT, MRI, bone scan, PET scan or any other standard of care imaging) performed within the last 3 months in spite of standard oncologic interventions and/or inability to tolerate standard oncologic interventions
5. Life expectancy at least 4 weeks
6. Age≥ 18 years
7. Patients of childbearing potential (male or female) must practice adequate contraception due to possible harmful effects of radiation therapy on an unborn child
8. Patient must have the ability to understand and the willingness to sign a written informed consent document
9. All patients must be informed of the investigational nature of this study and must be given written informed consent in accordance with institutional and federal guidelines

Exclusion Criteria:

1. Prior brain radiation
2. Patients must not have a serious medical or psychiatric illness that would, in the opinion of the treating physician prevent informed consent or completion of protocol treatment
3. Isolated localized pain amenable to focal radiation therapy, or pain well controlled by opioids, medical management, injections/ablation or surgical intervention
4. Malignancies being managed with curative intent
5. Life expectancy <4 weeks
6. The tumor amenable to curative management