To evaluate maximum variations in position of the vagina and lymph node regions caused by bladder filling and emptying.
To accurately measure day-to-day variations in the position of the vaginal vault and pelvic lymph node regions during a 5-week course of intensity modulated pelvic radiation therapy.
To evaluate the reproducibility of bladder filling throughout a five-week course of pelvic intensity modulated radiotherapy in patients who have been instructed to use a specified schedule of fluid intake; this will permit up to more accurately define the minimum margins that could safely be used with intensity modulated radiotherapy to the pelvis after hysterectomy.
To measure the effect of variations in bladder and rectal volume on the doses that would be delivered to tumor, bladder, rectum, and small bowel using theoretical treatment plans with reduced margins.
To evaluate the nature and prevalence of acute and late toxicity and their relation to the volume of tissue irradiated with IMRT. |