This study evaluates acute patient-reported bowel quality of life (QOL) and rectal bleeding in prostate cancer patients treated with combination external beam radiation (EBRT), low-dose-rate brachytherapy (LDR-BT), and SpaceOAR.

A retrospective review of prostate cancer patients treated with EBRT (45 Gy), cesium-131 LDR-BT (85 Gy), and SpaceOAR was conducted. Patient-reported acute (≤3 months after LDR-BT) bowel QOL and rectal bleeding was analyzed from Expanded Prostate Cancer Index Composite (EPIC) questionnaires. Five-point changes in mean bowel QOL scores were considered clinically significant. Clinically significant rectal bleeding was bleeding occurring more than "rarely" ("about half the time," "usually," or "always"), and clinically significant bleeding bother was considering bleeding a "small, moderate, or big problem." Outcomes were analyzed using descriptive statistics and paired t-tests.

69 patients were identified. Bowel summary, function, and bother scores clinically and significantly decreased 2 weeks after LDR-BT (79.9 ± 15.6, 80.5 ± 15.4, and 79.4 ± 18.1, respectively) compared with pre-EBRT scores (92.3 ± 9.1, 93.3 ± 9.0, and 92.6 ± 11.9, respectively) and pre-LDR-BT scores (91.1 ± 11.0, 91.6 ± 9.8, and 90.6 ± 13.3, respectively), but returned to clinical and statistical baseline pre-EBRT values at 3 months (88.7 ± 12.4, 88.8 ± 11.1, and 88.7 ± 14.5, respectively). The 3-month cumulative incidence of clinically significant rectal bleeding and bleeding bother was 4.35% and 2.90%, respectively.

With combination EBRT, LDR-BT, and SpaceOAR, bowel QOL returned to the baseline 3 months after LDR-BT. Clinically significant rectal bleeding was <5%. Further followup will confirm if low acute rectal toxicity translates to reduced late toxicity.