A prospective study of health-related quality-of-life outcomes for patients with low-risk prostate cancer managed by active surveillance or radiation therapy

Abstract

Introduction: Patients with low-risk prostate cancer (PCa) often have excellent oncologic outcomes. However, treatment with curative intent can lead to decrements in health-related quality of life (HRQoL). Patients treated with radical prostatectomy have been shown to suffer declines in urinary and sexual HRQoL as compared to those managed with active surveillance (AS). Similarly, patients treated with external-beam radiation therapy (EBRT) are hypothesized to experience greater declines in bowel HRQoL. As health-related quality-of-life (HRQoL) concerns are paramount when selecting among treatment options for low-risk PCa, this study examined HRQoL outcomes in men undergoing EBRT as compared to AS in a prospective, racially diverse cohort.

Methods: A prospective study of HRQoL in patients with PCa enrolled in the Center for Prostate Disease Research (CPDR) Multicenter National Database was initiated in 2007. The current study included patients diagnosed through April 2014. HRQoL was assessed with the Expanded Prostate Cancer Index Composite (EPIC) and the Medical Outcomes Study Short Form (SF-36). Temporal changes in HRQoL were compared for patients with low-risk PCa managed on AS vs. EBRT at baseline, 1-, 2-, and 3 years post-PCa diagnosis. Longitudinal patterns were modeled using linear regression models fitted with generalized estimating equations (GEE), adjusting for baseline HRQoL, demographic, and clinical patient characteristics.

Results: Of the 499 eligible patients with low-risk PCa, 103 (21%) selected AS and 60 (12%) were treated with EBRT. Demographic characteristics of the treatment groups were similar, though a greater proportion of patients in the EBRT group were African American (P = 0.0003). At baseline, both treatment groups reported comparable HRQoL. EBRT patients experienced significantly worse bowel function and bother at 1 year (adjusted mean score: 87 vs. 95, P = 0.001 and 89 vs. 95, P = 0.008, respectively) and 2 years (87 vs. 93, P = 0.007 and 87 vs. 96, P = 0.002, respectively) compared to patients managed on AS. In contrast to those on AS, more than half the number of patients who received EBRT experienced a decline in bowel function (52% vs. 17%, p=0.003) and bother (52% vs. 15%, P = 0.002) from baseline to 1 year. Patients who received EBRT were significantly more likely to experience a decrease in more than one functional domain (urinary, sexual, bowel, or hormonal) at 1 year when compared with those on AS (60% vs. 28%, P = 0.004).

Conclusions: Patients receiving EBRT for low-risk prostate cancer suffer declines in bowel HRQoL. These declines are not experienced by patients on AS, suggesting that management of low-risk prostate cancer with AS may offer a means for preserving HRQoL following prostate cancer diagnosis.

Keywords: Active surveillance; Prostate cancer; Quality of life; Radiotherapy; Treatment.