Adjuvan Radyoterapi Planlanan Jinekolojik Kanserli Olgularda Radyoterapi Sırasındaki Kilo Değişiklikleri ve Organ Hareketlerine Bağlı Dozimetrik Değişikliklerin İncelenmesi

Abstract

In this study, planned curative surgery and postoperative adjuvant radiotherapy (RT), 10 patient with gynecological tumors taken for planning purposes at the beginning of treatment with computed tomography (CT) taken in 3rd and 5th weeks making fusion target volumes and organs at risk (OAR) was examined shifts. Planning target volume (PTV) was to investigate whether there are sufficient safety for granted. CT, knee and heel supported and unsupported was done in two different ways and knee and heel supported (DTD) position on the set-up and internal margin effects were examined. In CT images taken at different times, 15mm safety was found to be sufficient for the primary tumor bed (CTV) and using DTD was detected not create a difference. The maximum deviation was seen in the presacral CTV and PTV safety of 0,5cm was faound to be not sufficient. Superior-inferior, anterior-posterior directions on presacral CTV at 30-60% patients PTV transcends the limits of deviation, while the right-left direction was found to be sufficient safety. In illiac CTV showed the greatest deviation superior-inferior direction. However PTV transcends the limits of deviation was detected is only 10-20% of patients. Deviations in the lymphotic CTV, the DTD found no difference between used and unused. Safety for iliac and presacral CTV to be 7mm and 10mm were re-analyzed. When not used DTD, 7mm margin was adequate for iliac CTV. 7mm safety created for presacral PTV was not found enough. DTD was no significiant difference between the used or non-used. Actual shift on presacral CTV was the anterior-posterior direction. Even when given 10mm safety, 20-30% of patients showed that extends beyond the safety limit of deviation. In our study of OAR in intensity modulated radiation therapy (IMRT) planning CT scans taken at different times in the same plan was made and their doses were also assessed. When used DTD, in the rectum volume V50 was reduced on the 5th week. Similarly V45 and V50 bladder volumes were lower in the case of using the DTD. As a result of gynecological tumors in the postoperative adjuvant IMRT planning safety margin of 15mm is sufficient given to CTV. However minimum of 7mm safety must be given to illiac CTV. For presacral CTV obese patients and due to difference in hip position might be wide of the span should be kept in mind.