Imaging methods are critically important in cancer clinical trials to define disease extent and to assess response of the cancer to treatment. The Imaging and Response Assessment Core (IRAC) is a shared resource that focuses on accurate and reproducible imaging assessment for tumor characterization and for determining response to therapy in clinical cancer research. Great care is taken to ensure the service provides accurate measurements of CT, MRI and PET/CT imaging data and that the services are delivered in a timely fashion. All results are reviewed by a Board-certified radiologist.

Core Description

The Imaging and Response Assessment Core (IRAC) provides centralized services, including quality control and image analysis, for tumor characterization and response assessment by conventional (and novel) imaging methods for research studies and clinical trials conducted at the Siteman Cancer Center (SCC). Prior to the formation of the IRAC, standardized and coordinated imaging services were unavailable at WUMC. Hence, delivery of these services through a shared resource provides SCC investigators with access to reproducible and rapid therapeutic response assessments, and plays an important role in testing new treatments for cancer.

The IRAC assists in building imaging science into institutional clinical research early in project development, thus capitalizing on the use of imaging biomarkers of tumor response.  The goal is to provide critical information for optimum management and interpretation in tumor response assessments for Phase I, II and III clinical trials.

The IRAC service operates out of the Radiology Clinical Research Core (RadCore) and the Division of Nuclear Medicine in the Mallinckrodt Institute of Radiology. Areas of emphasis for the IRAC efforts include: engagement of imaging specialists during the early phases of protocol design; improvement of awareness, understanding and efficiency of how imaging can be used; and, the expansion of unfamiliar or novel types of structural or functional imaging into a therapeutic trials. The IRAC works closely with the Center for Clinical Imaging Research (CCIR) and can facilitate use of the services provided by this facility.


Service available to Washington University and other non-profit organizations.

Priority service for Specific groups, centers or departments – see Additional Information for details.

Additional information:

Priority is given to Siteman Cancer Center CCSG members. ​​


  • The IRAC can accommodate a wide variety of study protocols that require tumor imaging and response assessment. The services available for these studies include:
  • Expert advice on how to integrate imaging into research study designs, and protocol development
  • Assistance in identifying the image response assessment criteria and personnel needed to support a particular study
  • Site qualification for imaging for cooperative group and industry-sponsored multicenter clinical trials
  • Research coordinator services required for execution of specialized imaging examinations
  • Coordination of the response assessment activities and reporting, including data interception at the time of acquisition and subsequent routing to appropriate workflow lists for processing
  • Actual measurement of radiologic data used to evaluate tumor response by a trained radiologist and/or nuclear medicine physician.


  • The IRAC operates as a virtual service. Images to be evaluated are transferred to dedicated servers and can be assessed on workstations throughout the medical center. All workstations are connected via the Washington University Clinical Operations private network (WUCON) to the PACS server which provides a central electronic archive that makes data available for immediate soft-copy review, printing, or electronic transmittal to research consoles.
  • The primary software tool used for tumor measurements on CT and MR images is Mint Lesion.
  • Additional dedicated PET/CT (and PET/MRI) workstations are available in the CCIR and in nuclear medicine for analysis of PET imaging data.


Please contact this core directly for pricing information.

Center for Clinical Imaging Research (CCIR)
Division of Nuclear Medicine
Division of Diagnostic Radiology
Mallinckrodt Institute of Radiology