Neutron interstitial brachytherapy for malignant gliomas: a pilot study

Area of Science:

• Oncology
• Radiation Oncology
• Neurosurgery

Background:

• Malignant gliomas are aggressive brain tumors with poor prognoses.
• Conventional therapies often result in significant side effects due to radiation necrosis.
• Neutron radiation shows potential for eradicating gliomas but faces challenges with widespread necrosis.

Purpose of the Study:

• To evaluate the efficacy and safety of interstitial neutron brachytherapy using Californium-252 (252Cf) in malignant glioma patients.
• To assess if 252Cf implants can improve tumor dose while sparing normal brain tissue.
• To compare survival outcomes with conventional therapies.

Main Methods:

• Fifty-six patients with malignant glioma underwent surgical debulking followed by CT-guided 252Cf interstitial neutron implant brachytherapy.
• 252Cf sources were removed after delivering approximately 300 neutron rads.
• Patients received subsequent external beam photon radiation (6000-7000 rads).
• Total photon-equivalent dose ranged from 8100 to 9100 rads.

Main Results:

• Median survival time was 10 months, with 18- and 24-month survival rates of 28% and 19%, respectively.
• Tumor recurrence was observed, but radiation necrosis was confined to the original tumor area.
• Serious complications (9%) included wound infections, cerebral edema, and limited radiation necrosis beyond the tumor margin.

Conclusions:

• Interstitial neutron radiation with 252Cf implants is a safe method for treating malignant gliomas.
• This technique allows for increased tumor dose and reduced normal brain exposure.
• Survival results are comparable to existing conventional therapies, offering a viable treatment option.