Sono-Photodynamic Therapy (SPDT)
Sono-photodynamic therapy, or SPDT, combines ultrasound (sono) and light (photo) to target cancer cells. Sono-photodynamic therapy arose out of research into sonodynamic therapy and photodynamic therapy. Both therapies have independently shown an ability to kill cancer, and both are enhanced by the use of a sensitizing agent which increases the cancer cells sensitive to both sound and light application.
Research has shown that sono-photodynamic therapy promotes apoptosis (programmed cell death) in cancer cells, disrupts tumor neovascularization, activates the immune system, while also acting to oppose metastasis.
Sono-Photodynamic Therapy in Use
The SPDT procedure entails first administering a sensitizing agent, which is uniquely retained in cancer cells but not healthy cells. This sensitizing agent makes cancer cells more susceptible to specific frequencies of therapeutic ultrasound and precise wavelengths of red and near infrared light. It is imperative to use the proper sensitizing agent, as well as the correct type of ultrasound and light applications.
The sensitizing agent we use is given orally, and remains inside cancer cells for a period of up to two weeks. During this time, the specific frequencies of therapeutic ultrasound and wavelengths of light are administered to take advantage of the susceptible cancer cells. The reactive oxygen species (ROS) generated are harmful to the cancer cells.
Each sono-photodynamic therapy session consists of the external application of a therapeutic ultrasound probe. These are applied over the skin in a patient-specific manner, tailored to the area(s) corresponding to each patient’s cancer involvement. The site of application can be the same each time, or it can be adjusted for each treatment.
An advantage of sono-photodynamic therapy is that it is an ablative treatment which uses no radiation, with the ability to target cancer cells while not harming nearby healthy tissue. Not surprisingly, it is an extremely well-tolerated treatment.