The aim of this study is to develop new tools using magnetic resonance imaging (MRI) that will improve the brachytherapy procedure and treatment for participants with gynecologic cancer.

This research study is designed to develop new technology using MR imaging to improve the brachytherapy procedure for participants with gynecologic cancer. The brachytherapy procedure will take place in an MRI procedure room within the Advanced Multimodality Image-Guided Operating (AMIGO) suite at Brigham and Women's Hospital. The purpose of the study will be to evaluate whether the use of an MR-tracking device will improve the placement of the brachytherapy catheters. This information will also be used to develop new software for real-time brachytherapy planning by our physics team. The investigators believe that the development of an MR-tracking device will allow them to better place the brachytherapy catheters for radiation treatment and ultimately improve outcomes for patients, including better local tumor control and a lower risk of side effects. The investigators will also evaluate new MRI protocols to better define the tumor at the time of brachytherapy. The brachytherapy treatment planning and delivery will follow standard of care.

In the past, brachytherapy treatment planning and delivery for gynecologic cancer was based on plain-film X-rays, which did not account for the shape of the tumor, the unique anatomy of an individual patient or the response to pelvic radiation therapy. In the last decade, advances in technology have made it possible to perform the brachytherapy procedure and to plan the delivered radiation dose based on CT or MR imaging. The use of CT or MR imaging for brachytherapy planning is increasingly common in the United States, and has been shown to result in improved tumor controls rates and a lower risk of radiation complications. The use of MRI-guidance during the brachytherapy procedure is unique and this study will contribute the advancement of this important technology. About half of the participants in this study will be selected to have the MRI-guided brachytherapy procedure with the use of an MRI-tracking device. This device will provide real-time positioning information of the individual brachytherapy catheters while they are being placed and adjusted within the tumor. The MR-tracker will also be used to develop new software that will allow our physics team to generate a near-instantaneous brachytherapy plan as individual catheters are placed during the procedure. The investigators hope that these advances in technology will have a meaningful impact on further increasing tumor control and limiting the complication risk for our participants.

Inclusion Criteria:

• Ability to understand and the willingness to sign a written informed consent document. Subject is willing and able to comply with the protocol for the duration of the study including undergoing treatment and scheduled visits and examinations including follow up.
• Participants must have a biopsy-proven diagnosis of primary or recurrent gynecologic cancer for which intracavitary or interstitial brachytherapy is planned as standard treatment. Eligible disease sites include primary or recurrent cancer of endometrial, ovarian, cervical, vaginal, or vulvar origin.
• Age of 18 years or older are eligible.
• ECOG performance status of 2 or less.
• Patients who have received prior radiation or chemotherapy may be enrolled on this study.
• Participant is deemed to be an appropriate candidate for MRI-guided brachytherapy by the radiation oncologist and the patient elects to be treated with MRI-guided brachytherapy.
• Participant provides informed consent for prospective collection of relevant medical records for analysis of clinical outcome and treatment-planning techniques.

Exclusion Criteria:

• Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, uncontrolled hypertension, interstitial lung disease, active peptic ulcer disease or gastritis, active bleeding diatheses, serious chronic gastrointestinal conditions associated with diarrhea or psychiatric illness/social situations that would limit compliance with study requirements.
• Contraindication to MRI identified by the MR procedure screening form, such as a pacemaker, aneurysm clip, inner ear implant, neurostimulator, or other non-MR compatible implant or device.