2458 - Too Full to Fail? Impact of Excessive Bladder Filling on Patient Experience in Prostate Cancer Radiotherapy

Purpose/Objective(s): Bladder filling for prostate radiotherapy (RT) is critical for pushing bowel away and reducing irradiated bladder volume. This process, however, can be frustrating for patients who struggle to maintain a very full bladder for treatment. We hypothesized that patients with overly full bladders at simulation (sim) would experience longer treatment times, more delays, and greater worry and frustration with RT.

Materials/Methods: We retrospectively analyzed the bladder size at sim, average duration of treatments, times taken off table, and subjective experiences of prostate cancer patients undergoing fractionated RT across 3 centers at our institution over 9 months. Bladder size was measured from dome to trigone on sagittal view. Patient experience was assessed by two questionnaires collected from each patient at first and last week of RT with answers scored on Likert scale from 0 (“Not at all”) to 4 (“Very much”). We also identified a group of subsequently treated patients who initially presented with very large bladders but were coached to reduce bladder size at sim (“Corrected bladders”). Comparisons between groups were assessed by two-sample t-test.

Results: We identified 211 consecutive prostate RT patients during the study period with characteristics shown in Table 1. The average treatment time per fraction for large bladder (defined as >10cm) patients was 498.5 sec vs 444.0 sec for all others (p=0.01). The number of times taken off table per week for inappropriate bladder filling was 0.14 vs 0.04 (p<0.0001). Patient experience was significantly worse in large bladder patients with scores of 1.58 vs 0.90 (p=0.001) for “I worry about filling my bladder correctly” and 1.06 vs 0.65 (p=0.03) for “I feel frustrated by bladder filling for treatments” on the final week questionnaire. The separate cohort of 20 patients with Corrected bladders had significantly shorter treatment times of 425.2 sec (p=0.03) compared to the uncorrected >10cm bladder patients.

Conclusion: Patients who are simulated with large >10cm bladders experience longer treatment times, more times off table, and worse anxiety and frustration with RT. Coaching patients to empty their bladders to a more comfortable level shows high potential to reduce treatment delays and improve patient experience during RT for prostate cancer.