Adoption Radiation Therapy Backgrounder

Siemens Medical Solutions Oncology Care Group has identified Adaptive Radiation Therapy (ART) as the future for radiation treatment management and delivery. The company now uses ART as a framework to describe and identify its vision for a product and solutions roadmap.

The need for ART in clinical practice is an acknowledgment that to deliver “best in class” therapy usually requires adjustment of the patient position prior to treatment, as patients cannot always be readily positioned in an identical manner to that observed during simulation. However, in some cases, this positioning requirement could possibly be better served for both the patient and efficient workflow by adjusting the treatment plan or even the treatment delivery, if the technology to achieve this was available.

Siemens uses the term “closing the loop” to introduce the company’s ART portfolio in recognition of the requirement to “sense” and “feedback” information at the time of treatment to appropriate key points in the traditional “feed forward” radiotherapy workflow in order to implement these ART strategies.

To clearly describe Siemens’ planned ART offerings, a family of terms has been developed that identify what is “sensed” in different Radiation Therapy Guidance solutions.

• Image Guided Radiation Therapy (IGRT) is already well used in the market place and our competitors use the term to describe their kV cone beam technology offering. Siemens uses IGRT to identify solutions that reference iconic 2D image information. Examples are MV port films, kV X-rays and fluoroscopy.


• When the “sensed” information that is a 3D iconic data set Siemens terms the solution Volume Guided Radiation Therapy (VGRT). This is relevant to CT, cone beam and 3D ultrasound solutions.


• If the “sensed” data includes 3D iconic data and structures as symbolic information, then the term Structure Guided Radiation Therapy (SGRT) is used.


• Following this approach, if in addition to 3D data and structures, symbolic dose information is “sensed,” then Siemens terms the solution Dose Guided Radiation Therapy (DGRT).

IGRT and VGRT provides feedback that can be utilized to adjust the patient setup, while SGRT introduces the further possibility to adjust the plan and DGRT provides an additional opportunity to confirm or adjust the dose volume relationship that is uniquely linked to the planned prescription.