CT Volumetry Biomarker Ctte

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This Wiki is for collaborative creation of QIBA's Volumetric CT Technical Committee materials and ongoing activities.


Mission: Investigate the technical feasibility and medical value of quantifying longitudinal changes in volume with CT.

Initial Objectives:

  • Characterize the precision and accuracy of volumetric tumor measurements.
This will be an essential prelude for understanding the threshold that will be needed to classify longitudinal changes in tumor volume as medically meaningful surrogates for changes in health status.
  • Compare the sensitivity of volumetric measurements to RECIST/ World Health Organization (WHO) (conventional & modified) outcome measures.
This will be necessary in order to determine if Progressive Disease can be detected significantly sooner with volumetric techniques than with uni- or bi-dimensional line-lengths placed on a single slice.


In a graphic, therapy assessment looks like this (this slide and the two following courtesy R. Avila):

Therapy Assessment.jpg


The present defacto standard applies the following methodolgy:

RECIST Baseline.jpg


Our goals are to address bias and variance, which in turn outght to allow shorter trials and/or lower enrollments:

We Can Do Better.jpg


To accomplish this, we adopt the following flow which represents the structure of our effort as well as the resulting output we achieve:

QIBA Process for VolCT.jpg

Project Snapshot

Quantitative Response Metrics for Lung Cancer was selected as a useful concrete focus to get started.

Profiling Activities

Write Profile documents to which equipment and sites can conform to accomplish Quantification goals.


  • Radiology 2007 - Coronary Calcium Scoring - This paper by Dr. McCollough et al is very analagous to our profiling work and addresses many similar issues (e.g. achieving "standard" noise levels). It could be thought of as an early draft of a Calcium Scoring profile, including both groundwork and equipment specifications.

Groundwork Activities

Validate key concepts and answer key questions needed to write the Profiles and demonstrate their effectiveness.

  • VolCT - Group 1A - Analyze Bias/Variance where Ground Truth is Known Deterministically
  • VolCT - Group 1B - Focus on Volume Change Analysis of Pulmonary Nodules in Diagnostic Settings
  • VolCT - Group 1C - Model Sources of Variability from a Systems Engineering Analysis
  • VolCT - Group 2 - Set Standards for using Volumetric Imaging in Clinical Trials

Working Documents


  • Are we ready? A time for measurement of physiological parameters of the lung using multidetector row CT scans. Hatabu H. Acad Radiol. 2009 Mar; 16(3):249. Academic Radiology
  • Helical multidetector row quantitative computed tomography (QCT) precision. Bligh M, Bidaut L, White RA, Murphy WA Jr, Stevens DM, Cody DD. Acad Radiol. 2009 Feb; 16(2):150-9. Academic Radiology
  • Comparison of the accuracy of CT volume calculated by circumscription to prolate ellipsoid volume (bidimensional measurement multiplied by coronal long axis). Rkein AM, Harrigal C, Friedman AC, Persky D, Krupinski E. Acad Radiol. 2009 Feb; 16(2):181-6. Academic Radiology

Slide Presentations

MSK Coffee Break Image Sets

See the Datasets page of the QIBA Resource Catalog

Meetings / Call Summaries