- We used my agent model calibration technique, plus a volume-averaging upscaling to calibrate a simplified continuum model of DCIS growth in the breast.
- We used the steady-state approximation of the continuum model to estimate the DCIS volume.
- We applied this technique to 17 cases and found a very good match in predicted vs. pathology volume in 14 of 17 cases.
- We also found that the model was a much better predictor of volume than mammographic estimates (although this can vary with how the mammography is processed).
- We found that the mathematical theory predicted that a single variable A--a ratio of the apoptotic index, the proliferative index, and the estimated intraductal oxygenation--is a better predictor of tumor volume than grade, PI, or AI alone.
The last finding is significant, because you can AI and PI from fairly standard immunohistochemical stains (cleaved Caspase-3 and Ki-67), and oxygenation can be estimated from histopathologic measurements of the viable rim size when comedonecrosis is present. These things can likely be done on pre-operative biopsy tissue.
In the long term, this could prove useful for improved surgical planning. Right now, second surgeries are required in 50% or more DCIS lumpectomies due to inadequate pre-surgical estimates of tumor shape and volume.
More to come when I post the preprint tonight or tomorrow.
Edit on Sept. 8, 2011 at 11:22 am PDT:
Preprint is now online:
http://www.mathcancer.org/publications/edgerton11_ACP(preprint).pdf
Edit on Sept. 8, 2011 at 11:22 am PDT:
Preprint is now online:
http://www.mathcancer.org/publications/edgerton11_ACP(preprint).pdf