3688 - Association of Patient Comorbidities with Treatment Regret in Prostate Cancer: Results from a Population-Based Prospective Cohort

R. D. Mali¹, Y. Cao¹, A. Katz², K. Kane¹, Y. Xie³, D. S. Usinger⁴, X. Shen¹, and R. C. Chen¹; ¹Department of Radiation Oncology, University of Kansas Medical Center, Kansas City, KS, ²Department of Population Health, University of Kansas Medical Center, Kansas City, KS, ³Kansas College of Osteopathic Medicine, Wichita, KS, ⁴University of North Carolina at Chapel Hill, Chapel Hill, NC

Purpose/Objective(s): Patient-reported regret is an established, patient-centered outcome in prostate cancer, but patient factors associated with regret have not been well-studied. We hypothesize that patient baseline comorbidities, which impact treatment tolerability, are associated with regret. Materials/

Methods: The North Carolina Prostate Cancer Comparative Effectiveness & Survivorship Study (NC ProCESS) is a population-based cohort which enrolled, through the state cancer registry, patients with newly diagnosed prostate cancer from 2011 to 2013 from all 100 counties of the state. Participants were followed prospectively. Decisional regret was assessed using a validated scale developed by Clark et al (JCO 2003) at 12 months post treatment and scored following its instructions. In addition, patient-reported quality of life was assessed using the validated Prostate Cancer Symptom Indices (PCSI) with urinary obstruction, urinary incontinence, bowel and sexual domains at baseline and in follow-up. Comorbidity was scored with medical record abstraction using the validated NCI comorbidity index. Logistic regression analysis was used to evaluate the association between comorbidities with regret, adjusting for patient characteristics, cancer risk group, treatment received, and treatment-related symptoms (PCSI change from baseline to 12 months).
Results: 981 participants completed the regret survey. This is a socio-demographically diverse cohort with 25% Black race, 24% living in rural areas, and 30% with high school education or less. Overall, 11% reported decisional regret at 12 months. On multivariable analysis, comorbidity burden (OR 1.59, p=.04), treatment (radical prostatectomy higher, RT lower, p=.05), not married (OR 1.89, p=.02) and change in patient-reported bowel problems (OR 2.10, p<.01) were associated with decision regret (Table).
Conclusion: Among men with localized prostate cancer, baseline comorbidity is associated with treatment regret. Further, radical prostatectomy is associated with more regret than radiation therapy and active surveillance. These results illustrate the importance of personalizing prostate cancer treatment decisions based on baseline comorbidities to minimize post-treatment adverse outcomes. Abstract 3688 – Table 1: Multivariable logistic regression analysis of factors associated with decision regret

	OR	P-value
NCI Comorbidity Index score: >0 (vs 0)	1.59	.04
Not married (vs married)	1.89	.02
Treatment groups (REF: radical prostatectomy)		.05
Active surveillance	0.58
Brachytherapy	0.76
External beam radiation therapy	0.34
Other	0.88
PCSI Bowel Problems: worsened (vs improved/no change)	2.10	<.01
Not significant: age at diagnosis, race, urban/rural residence, household income, NCCN risk group, other PCSI domains (sexual dysfunction, urinary obstruction, urinary incontinence).