IHERO UseCase Structure template

1. Proposed Workitem: Clinical trials submission I-Structure Template Creation, Import, and Export

Proposal Editor: Charles Able, MS
Editor: C. Field
Editor: M. Wahab
Date: N/A (Wiki keeps history)
Version: N/A (Wiki keeps history)
Domain: Radiation Oncology

Summary

The use of anatomical structures and structure sets is fundamental to image based treatment planning and delivery but the portability and customization of structure templates does not exist. DICOM handling of a single structure set associated with an image data set is established. Development of the structure template profile will allow the use of defined templates in building a structure set with established naming conventions. The Image Guided Therapy QA Center (ITC) and CABig have promoted and developed uniform tissue names for use in radiation oncology clinical trials. The expanded use of structure templates will increase productivity across the field of radiation oncology (virtual simulation, treatment planning and IGRT, and image review). The expanded use of structure sets and templates requires the development of well defined handling processes across platforms and systems. This makes it an ideal integration profile for the IHE-RO.

2. The Problem

1. Specific structure templates may be developed by cooperative oncology groups for certain protocols. Treatment planning systems need to be able to import the structure templates to allow for consistent identification and evaluation of clinical data for national clinical trials.

2. The use of standard naming conventions (i.e. ATC's Uniform Tissue Names for use in RTOG Advanced Technology Clinical Trials, caBIG naming convention, etc.) has not been adopted to date by the radiation oncology community. Structure Template Import/Export capability will accelerate the standardization of tissue naming.

3. Different structure templates are needed at various stages of the radiotherapy process (i.e. virtual simulation, treatment planning, image guided therapy). The ability to build, activate, and/or disable structure templates or a subset of structures (sub-template) for use at each stage of the radiotherapy process is needed.

4. The need to import and export structure templates for patients being treated at multiple institutions using different platforms exists. Patients being transferred or receiving re-treatment could benefit from the ability to import and export the structure template.

Lost productivity is at the heart of this problem. The Advanced Technology QA Consortium's Image Guided Therapy QA Center (ITC) has developed software tools to assist in reconciling discrepancies between submitted and protocol-specified structure names. Some cases still require visual inspection of images, contours to identify structures. The ITC states "the effort required to correctly identify all structures can be substantial."

The time required to re-create structures used repeatedly for specific body sites can be substantial for therapist and dosimetrist when performing virtual simulation and treatment planning. Additional time is lost during IGRT implementation by the therapist and radiation oncologist eliminating unwanted structures when reconciling the patient position. Further lost productivity results when the radiation oncologist reviews images off line when structures viewed must be customized each time an image is taken during the course of treatment.

Development of this use case can increase productivity across the field of radiation oncology.

3. Key Use Case

How It Currently Works

Patient X enters on a National Cooperative Group Trial:

1. The planner determines the structure names (spelling and abbreviations) used based on the specifics of the protocol. A treatment plan is prepared in which these structures may be copied and expanded to develop structures specific to the problem of inverse planning (Helper or Avoid structure types) or IGRT evaluation structures that have no direct bearing on what is required for the clinical trial. These additional structures may have names that are similar to or abbreviations of the protocol required structures and adds complexity and quantity to the structure set. Even worse, a radiation oncologist Approved planning Structure Set which is exported from planning system to information management system, may have structures subsequently deleted, to simplify IGRT evaluation (hence, causing confusion as to which set relates to which part of the process).

2. The plan is reviewed and approved for treatment by the radiation oncologist.

3. The plan needs to be anonymized and transferred to the Cooperative group. The list of contoured clinical structures can be uploaded into a structure template containing the nomenclature and format identified by the cooperative group along with the complete treatment plan DICOM file.

4. The structures contained in the DICOM file are reconciled using software tools. If the software reconciliation is incomplete the file is rejected and a manual review is performed.

5. The file is edited and submitted for further review.

6. The plan can now be reviewed and evaluated for acceptance in the cooperative clinical trial.

How It Should Work

Patient X enters on a National Cooperative Group Trial:

1. The planner imports the structure template into the planning system from the cooperative group for the specific trial. A treatment plan is prepared in which these structures names and others (inverse planning structure template, and image evaluation structure template) may be imported into the contouring workspace. Structures can be grouped into subsets depending on their use or application to different processes (i.e. treatment planning & BEV display, DVH calculation and dose evaluation, inverse planning Helper or Avoid, IGRT, or image review).

2. The plan is reviewed and approved for treatment by the radiation oncologist.

3. The plan needs to be anonymized and transferred to the Cooperative group. The required group of contoured clinical structures can be uploaded into a structure template containing the nomenclature and format provided by the cooperative group along with the complete treatment plan DICOM file.

4. The structures contained in the DICOM file are reconciled using software tools.

5. The plan can now be reviewed and evaluated for acceptance in the cooperative clinical trial.

6. Only the IGRT structure group is viewed at the treatment console and only the image review structure group is viewed in the off-line image reviewer.

Technical Subtext:

a. A DICOM file containing a list of clinical structure names can be imported into the treatment planning contouring workspace. Clinical structures can be contoured under each identifying structure name.

b. A DICOM file containing a list of clinical structure names can be created in the treatment planning contouring workspace. Clinical structures can be contoured under each identifying structure name.

c. Using an existing treatment plan a structure template can be created from the structures defined in the treatment plan. The newly created structure template can be exported as a DICOM file

4. Standards & Systems

Systems involved or affected: virtual simulation, treatment planning system, and oncology management systems (image review/approval).

5. Technical Approach

Existing actors

New actors

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Existing transactions

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New transactions (standards used)

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Impact on existing integration profiles

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New integration profiles needed

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Breakdown of tasks that need to be accomplished

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