Recent literature suggests that tumor cells and areas within tumors with a high initial FDG uptake might be more resistant to (chemo)radiotherapy ((C)RT). This study was undertaken to test this hypothesis in rectal cancer using rigid and non-rigid image registration.
van den Bogaard, J., Janssen, M. H. M., Janssens, G., Buijsen, J., Reniers, B., Lambin, P., Lammering, G., & Ollers, M. C. (2011). Residual metabolic tumor activity after chemo-radiotherapy is mainly located in initially high FDG uptake areas in rectal cancer. Radiotherapy & Oncology, 99(2), 137-141. https://doi.org/10.1016/j.radonc.2011.04.004 (Original work published 2011)