Clinical Trial Annotation Workflow

1. Proposed Workitem: Clinical Trial Annotation Workflow

• Proposal Editor: Clunie
• Editor: Clunie
• Date: 2010/09/08
• Version: 1.00
• Domain: Radiology

2. The Problem

Clinical trials involving measurement and annotation of images are difficult to perform at the clinical workplace (as opposed to dedicate custom workstations) due to lack of supporting features and work flow, despite existing standards for the encoding of the results.

By defining the features required, the choice of standards to be used for transfer and persistence, the means of extension to specific use cases, and the actors involved in the work flow, the value proposition for implementers can be made clear.

3. Key Use Case

A multi-center oncology clinical trial requires reporting by one or more on-site readers of images acquired at that site at each visit, including measurement of lesion size, density, location and the answering of a specific series of protocol-specific questions with a coded set of answers. The subjects enrolled in the trial are undergoing clinical care, and the images, annotations and results are stored in the clinical PACS for subsequent follow up and management, as well as being extracted for the clinical trial coordinating center. The radiologist (or medical oncologist) reader at their ordinary PACS workstation will read the case, perform the annotations (manually or with the assistance of segmentation algorithms), and answer the protocol-specific questions. Good Clinical Practice (GCP) for clinical trials requires that the sites maintain an on-site record of their work that may be subject to inspection by regulatory agencies.

4. Standards and Systems

DICOM SR, Presentation States and Segmentation for storage within the PACS and transfer to other imaging systems.

HL-7 CDA for transfer outside the PACS to clinical information systems.

NCI cBIG AIM for within-actor handling of annotations +/- caGrid-based AIM Data Services

Ontology services for access to coded terminology, value sets and templates (such as NCI caDSR).

5. Discussion

The need to satisfy the entry of this type of information is clear, even if there are a myriad of potential incompatible technical solutions to the problems of workflow and encoding.

IHE is an appropriate venue for making the necessary technical choices and defining the workflow.

The Image Display and Evidence Creator actors are natural candidates for addition of the authoring and rendering functionality. The existing Consistent Presentation of Images (CPI) and Teaching File and Clinical Trial Export (TCE) profiles provide a basis to define the workflow and transactions.

Risks include potential difficulty of reaching consensus over the plethora of alternative competing approaches, as well as finding a natural path to extending the installed base of systems with proprietary or standard but unstructured annotation formats (like overlays and presentation states and RT structure sets).