Dosimetric comparison of 2-D and 3-D brachytherapy treatment planning at inoperable cervical cancerous patiences

In the treatment of inoperable cervical cancer, radiotherapy is essential. External and intracavitary radiotherapy (brachytherapy) are often applied together. With brachytherapy, when appling higher doses to the tumoral tissues, surrounding critical tissues can be protected from high doses. The purpose of this study is dosimetric comparison at 2-d and 3-d treatment planning of patiences diagnosed with inoperable cervical cancer. Therefore 2-d and 3-d plans of 20 patiences, who diagnosed with inoperable cervical cancer, had been done. Ten the target volume dose and dose to critical organs had been compared and evaluated statistically. In this study, 2-d brachytherapy treatment plans had been made accorrding to ICRU (International Commision of Radiation Units) 38 report. A reference point called "A" taken, and %100 dose normalised at point A. On the other hand 3-d brachytherapy treatment plans had been made through BT image and %100 dose normalised to CTV (Clinical Target Volume). At both brachytherapy treatment plannings; Isodoses, which contains %90 of target volume, had been determined. Also at both brachytherapy treatment plannings, intake doses acquaired at 2 cc volumes of critical organs. Then at both plannings, target volume and critical organ doses had been compared. As a result; At the plans, that made with normalisation to CTV, had seen insufficient. At the plans, that made with normalisation to reference point "A", had occured with better target dose volume. (doses exposed by target volume found to be statistically significant. (p<0,001)) When we evaluate in terms of critical organs; At the plans, that made with normalisation to CTV, doses had seen significantly lower. (p<0,001) At the plans, that made with normalisation to reference point "A", dose intake of critical organs had a tendency to increase.