open access - free: Imaging in Radiation Oncology: A Perspective -- The Oncologist

Note: not specific to ovarian cancer; paper addresses the importance of imaging techniques (ie; MRI/PET) while planning radiation therapies.  
some excerpts:
- Shortly after the discovery of the x-ray in 1895, the potential therapeutic benefits of the x-ray and possible toxicities were realized. More than a century later, we continue to struggle with how to balance the intensity of cancer treatment toward increasing the chance of cure with the potential for normal tissue toxicity. Imaging has improved our understanding of the complexities of cancer biology, cancer diagnosis, staging, and prognosis, and it is an essential component of present-day radiation oncology practice. Progress in radiation oncology has occurred in parallel to advances in imaging.
- The primary decisions that radiation oncologists make daily are to decide who to treat, what to treat, what to avoid, and how to deliver the intended doses safely. Imaging is considered in each of these decisions. Although the steps described in sequence below often occur simultaneously, they feed back to each other. Predictions about uncertainties and response in a specific patient can be made from experience in treating a population of similar patients or as more is learned about the patients themselves (e.g., with imaging obtained during therapy).
- How to define the gross tumor volume and volumes at risk for containing microscopic disease (clinical target volumes [CTVs]) is not an easy task. Different imaging tools demonstrate inherently different representations of the tumor

IGRT, SBRT Guidelines Issued By ASTRO, ACR

"The American Society for Radiation Oncology (ASTRO) and the American College of Radiology (ACR) have released practice guidelines for image guided radiation therapy (IGRT) and stereotactic body radiation therapy (SBRT) in the February issue of the International Journal of Radiation Oncology*Biology*Physics, the official journal of ASTRO."