Cooled microwave transrectal applicator with adjustable directional beam for prostate treatment

Area of Science:

• Medical physics
• Biomedical engineering
• Oncology

Background:

• Microwave hyperthermia is a promising cancer treatment modality.
• Effective and precise heating of target tissues is crucial for optimal therapeutic outcomes.
• Existing applicators face challenges in controlling heating patterns, particularly for deep-seated tumors like prostate cancer.

Purpose of the Study:

• To present a new intracavitary applicator design for microwave hyperthermia.
• To enable precise control over longitudinal and transverse heating patterns for transrectal prostate treatment.
• To evaluate the applicator's performance in terms of heating patterns and temperature distribution.

Main Methods:

• Design of an intracavitary applicator featuring an exchangeable multisection antenna for longitudinal control.
• Integration of a cooling system to manage surface temperature.
• Incorporation of a microwave reflecting system for transverse beam shaping.
• Performance evaluation using Specific Absorption Rate (SAR), electric field measurements, and temperature distribution analysis in tissue-equivalent phantoms.

Main Results:

• The applicator demonstrated independent control of longitudinal and transverse heating patterns.
• Measurements in phantoms confirmed effective heating of tissue volumes.
• The applicator successfully heated tissue radially 3-25 mm from its surface, with angular and longitudinal control.
• Previous clinical evaluations in a Phase I study showed effective heating capabilities.

Conclusions:

• The developed intracavitary applicator allows for precise and controllable microwave hyperthermia.
• This technology holds potential for improved transrectal prostate cancer treatment by enabling targeted tissue heating.
• The applicator's design facilitates customization of heating patterns to individual patient needs.