3136 - Patient Reported Quality of Life (QOL) Outcomes for Intermediate-High Risk-Very High Risk Prostate Cancers Treated By SBRT and Androgen Deprivation Therapy (ADT)

T. Basu¹, J. P. Sahu², S. Kamat², R. Menon², G. Roshan², A. U. Gadekar³, and R. Nair²; ¹HCG Cancer Center, Radiation Oncology, Mumbai, India, ²HCG Cancer Center Mumbai, India., Mumbai, India, ³HCG Cancer Centre, Mumbai, India

Purpose/Objective(s): We report the QOL outcome of Institutional prospective database of intermediate-high risk-very high-risk prostate cancers (Pca) treated by ADT and SBRT and utilizing Expanded Prostate Cancer Index Composite for Clinical Practice (EPIC-CP). Materials/

Methods: Consecutive series of 55 Pca between January 2019 to September 2023 were included. Linac based SBRT 36.25Gy in 5 fractions (25 Gy in 5 fractions for pelvic nodes for high-very high risk) on alternate days or once weekly. ADT was as per risk categorization. Baseline IPSS and PSA were documented. Urinary incontinence and obstructive symptoms, bowel symptoms scores, sexual symptoms, vitality/hormonal symptoms scores were documented by EPIC-CP questionnaire at baseline, SBRT completion and then 6 monthly till last follow up. We used the paired t-test to compare pre-treatment and post-treatment EPIC-CP domain scores and p-values < 0.05 was considered statistically significant. Dosimetry of rectum, bladder, bowel, penile bulb and bilateral neurovascular bundles were documented following standard guidelines.
Results: With median age of 71 years, 10.2% were NCCN intermediate risk and 89.8% were high-very high risk. 46.9% had moderate baseline IPSS. With Median follow up of 26 months (range 06–50 months), median baseline EPIC-CP urinary symptom score of 2.0 increased to 3.5 at the end of treatment (p < 0.0001). Prior to treatment, 10.2% of men felt that their overall urinary function was a moderate to big problem that increased to 28.5% by the end of the treatment and then decreased to 4.1% at the end of 6 months. A median baseline EPIC-CP bowel symptom score of 1.0 significantly increased to 1.5 at the end of treatment (p < 0.0001) and then further declined in subsequent follow up. Prior to treatment, 4.1% of men felt that their overall bowel function was a moderate to big problem that increased to 12.2% by the end of the treatment and decreased to 2.2% at 6 months. Median sexual symptoms score reported at baseline of 3 (range 0-4), at the end of treatment 5 (range 0-7) at 6 months 4.5 (range 3-10)), at 12 months 5 (range 3-12), at 24 months 5.5 (range 3-12) and at 30 months 7 (range 4-12). There was no significant change in median vitality/hormonal symptoms score. Median V14Gy for bladder and rectum was 44.3% and 43.5% respectively. Median V35Gy for bladder and rectum was 4.3% and 3% respectively. Mean dose to penile bulb was in range of 9.5-29.4Gy. NVB Dose ranged from V34.4Gy (83.3% - 91.8%), V32Gy (94.5-99.16%) V28Gy (99.76-100%). Till last follow up 94.5% were biochemically controlled with acceptable gastrointestinal and genitourinary late effects.
Conclusion: SBRT and ADT was safe with acceptable toxicity profile. As per EPIC CP transient increase in median urinary symptoms score, higher bowel symptoms scores in high risk and increasing sexual symptoms score till last follow up were major findings. Future project assessing impact of dosimetric factors on QOL besides SBRT and ADT will be of interest.