Incorporation of tumor shape into an assessment of spatial heterogeneity for human sarcomas imaged with FDG-PET.

Abstract

We have been exploring techniques for evaluation of fluoro-deoxyglucose (FDG) utilization characteristics in human sarcomas measured with positron emission tomography. In previous work, a measure of spatial heterogeneity based on evaluating the deviation of the FDG utilization distribution within the tumor region from a unimodal elliptically contoured spatial pattern was developed. This measure was shown to be a strong prognostic indicator of time to death. The present work explores a more general measure of heterogeneity which incorporates tumor boundary information. The approach relies on the use of a non-parametric representation for the tumor boundary surface. A set of 179 sarcoma patients with follow-up are evaluated with this technique. The results are analyzed to obtain empirical insight into the factors explaining elliptical heterogeneity. In terms of patient survival, the incorporation of the more sophisticated measure of spatial heterogeneity shows some potential improvement in the prediction risk. Further data will enable us to obtain a clearer empirical understanding of the role of the surface information in the measurement of tumor heterogeneity.

• Authors: F O'Sullivan, S Roy, J O'Sullivan, C Vernon, J Eary
• Journal: Biostatistics (Oxford, England) (Biostatistics) Vol. 6 Issue 2 Pg. 293-301 (Apr 2005) ISSN: 1465-4644 [Print] England
• PMID: 15772107 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Fluorodeoxyglucose F18

Topics

• Data Interpretation, Statistical
• Fluorodeoxyglucose F18
• Humans
• Models, Biological
• Positron-Emission Tomography
• Predictive Value of Tests
• Sarcoma (diagnostic imaging, pathology)
• Survival Analysis