Magnetic Resonance Imaging Guided Gynecologic Brachytherapy

Overview

The primary goal of this pilot study is to assess the feasibility of using magnetic resonance (MR) imaging guidance in the Magnetic Resonance Therapy (MRT) unit at the Brigham and Women's Hospital during the implantation of brachytherapy applicators in patients with gynecologic malignancies. Patients with gynecologic malignancies requiring brachytherapy are currently treated under either fluoroscopic or CT visualization of the brachytherapy applicator. Magnetic resonance imaging has been shown in many studies to provide superior visualization of the cervix, vagina and uterus compared to CT. However no prior study has examined the feasibility of using real-time magnetic resonance imaging to assist in the guidance of gynecologic brachytherapy applicators

The primary endpoint involves the ability of the MRT guided procedure to protect bladder and rectal tissues from inadvertent insertion of the interstitial needles used to deliver brachytherapy. MR images obtained on the MRT unit should provide clear delineation of the bladder and rectum and allow for greater accuracy and avoidance of these normal tissues upon interstitial needle insertion. CT images will be obtained following the insertion of needles using the MRT unit. The procedure will be considered a failure if CT imaging identifies the insertion of needles into the bladder or rectum that was not detected using MR. Secondary endpoints include the ability of MR imaging to accurately reconstruct dosimetric plans and to construct dose volume histograms after the implantation of interstitial needles as well as the ability of MR imaging to accurately determine tumor, bladder and rectal volumes. Secondary endpoints will also include the assessment of acute skin, genitourinary and gastrointestinal toxicities as well as an assessment of tumor progression or recurrence during a 180 day follow-up period.