Bladder and Rectal Dosimetric Doses Upon Magnetic Resonance Imaging Integrated Into Tandem and Ovoid Brachytherapy Treatment Planning

Abstract Introduction Brachytherapy is a common treatment for women that have cervical cancer. Patients can experience many side effects when receiving intracavitary treatment. Using more advanced imaging techniques such as MRI in the treatment planning process may be able to help reduce some of these side effects to the organs at risk and give patients an overall better quality of life during treatment and after treatment is complete. This study was performed to see if MRI has an impact in reducing these side effects to women undergoing these treatments. Methods This study is a retrospective chart review of 20 patients with Stage III cervical cancer. These patients were previously treated with Tandem and Ovoid brachytherapy and planned off CT or CT and MRI images at a hospital located in the Southeast. The subjects were selected at random, using the simple random method, mainly focusing on stage of cancer, number of treatments, how the treatments were planned and ensuring the bladder and rectal contours were averaging the same size. Each of the 20 patients were diagnosed with Stage III cervical cancer, completed five fractions of brachytherapy delivered with an 192Ir source and a single tandem and two symmetric ovoid applicators to a prescribed dose of 30Gy, 6Gy per fraction. Results The results displayed that the overall dose to the bladder and rectum were lower with patients that were planned using MRI and CT imaging compared to patients just planned off CT imaging. Bladder and Rectum volume plays a large role when comparing dose to patients and how they were planned. Conclusion This study suggests looking at Bladder and Rectum on the Dose Volume Histogram using D0.1cc, D1cc and D2cc. Once MRI planning was integrated into brachytherapy for cervical cancer patients using Tandem and Ovoids, the clinic did see an overall decrease in bladder and rectal doses compared to patients planned with only CT scans