Functional Imaging Strategies

Radiation therapy delivery is dependent upon accurate identification of the tumor target. Anatomic imaging has limited ability to define tumor borders, particularly within the pelvis. Functional imaging strategies (i.e. Magnetic Resonance imaging (MR) and positron emission tomography (PET)) take advantage of tumor-specific physiologic, micro-environmental and metabolic changes to localize areas of active tumor growth. We use a well annotated clinical database to evaluate the prognostic value of imaging metrics from 18F-fluoro-deoxy-glucose (FDG)-PET and MR imaging in cervical cancer. Samples from a prospectively collected tumor banking study are used explore how tumor biologic changes (i.e., mutations, gene expression, protein modifications and metabolites) are related to PET and MR imaging metrics.

MR imaging plays an essential role in defining targets for brachytherapy, and research by our group indicates that select MR imaging metrics are associated with post-radiation therapy outcomes. We have developed a clinically relevant model of human cervical cancer in the mouse.

Bioluminescence of female SCID mouse implanted with SiHa-CBG-GFP tumor in the cervix at Day 5, 15 and 63 post implant.

In this model, bioluminescent human cervical cancer cells are implanted directly into the cervix of immune compromised mice. These tumors grow, invade local structures and metastasize in patterns consistent with what we see in cervical cancer in humans. These tumors can be monitored non-invasively by bioluminescence, microPET and microMRI.

Most importantly, we can manipulate the tumor cells in vitro prior to implantation to directly test the function of individual genes and to evaluate the effects of common mutations. We are currently using this model to explore new therapeutic strategies, including biologics, in the treatment of cervical cancer.

Spin echo and diffusion weighted images of a mouse 33 days after tumor implantation.

Spin-echo images of a mouse 26 days and 33 days after orthotopic tumor implantation.