Clinical results with fast neutrons (DT, 14 MeV)

Area of Science:

• Oncology
• Radiation Oncology
• Medical Physics

Background:

• Conventional megavoltage therapy has limitations in treating certain advanced cancers.
• Neutron therapy, particularly with deuterium-tritium (DT) neutrons, has emerged as a promising alternative.
• Assessing the efficacy and safety of DT-neutron therapy is crucial for optimizing cancer treatment.

Purpose of the Study:

• To evaluate the curative effect of DT-neutron therapy on highly differentiated tumors.
• To compare the efficacy of DT-neutron therapy with standard megavoltage therapy.
• To assess the incidence of adverse effects, such as necrosis and fibrosis, in normal tissues.

Main Methods:

• A pilot study involving DT-neutron therapy was conducted in Hamburg.
• Standard doses of 15.6 Gy were administered over four weeks.
• Treatment schedules included fast neutrons alone or a photon-neutron combination for radiosensitive organs.

Main Results:

• DT-neutron therapy demonstrated the best curative effect on highly differentiated tumors.
• No necrosis was observed in normal tissues with standard doses.
• Local tumor control was superior to megavoltage therapy for specific cancers (thyroid, prostate, rectal, soft tissue sarcoma).
• A photon-neutron schedule may offer advantages over megavoltage therapy alone.

Conclusions:

• DT-neutron therapy, with sophisticated planning and adherence to tolerance doses, shows potential for improved outcomes.
• The therapeutic index of DT-neutrons is higher than that of cyclotron-produced neutrons.
• Further research into optimized DT-neutron therapy protocols is warranted.