ABSTRACT
Background Identifying the optimal management of high-risk non-metastatic prostate cancer (PCa) is an important public health concern, given the large burden of this disease. We performed a meta-analysis of studies comparing PCa-specific mortality (CSM) among men diagnosed with high-risk non-metastatic PCa who were treated with primary radiotherapy (RT) and radical prostatectomy (RP). Methods Medline and Embase were searched for articles between January 1, 2005, and February 11, 2020. After title and abstract screening, two authors independently reviewed full-text articles for inclusion. Data were abstracted, and a modified version of the Newcastle-Ottawa Scale, involving a comprehensive list of confounding variables, was used to assess the risk of bias. Results Fifteen studies involving 131,392 patients were included. No difference in adjusted CSM in RT relative to RP was shown (hazard ratio, 1.02 [95% confidence interval: 0.84, 1.25]). Increased CSM was found in a subgroup analysis comparing external beam radiation therapy (EBRT) with RP (1.35 [1.10, 1.68]), whereas EBRT combined with brachytherapy (BT) versus RP showed lower CSM (0.68 [0.48, 0.95]). All studies demonstrated a high risk of bias as none fully adjusted for all confounding variables. Conclusion We found no difference in CSM between men diagnosed with non-metastatic high-risk PCa and treated with RP or RT; however, this is likely explained by increased CSM in men treated with EBRT and decreased CSM in men treated with EBRT + BT studies relative to RP. High risk of bias in all studies identifies the need for better data collection and confounding control in the PCa research.
ABSTRACT
BACKGROUND: Research examining the association between physical activity (PA) and prostate cancer (PCa) has accumulated; however, few studies have examined this association in the context of active surveillance. The current study examines this among men initially diagnosed with favorable-risk PCa and managed by active surveillance at Sunnybrook Health Sciences Centre in Canada and the Royal Marsden Hospital in the United Kingdom. METHODS: Participants completed a questionnaire on daily participation in non-leisure, transport, and recreational PA. A logistic regression was employed using PA as the independent variable and whether the patient reclassified to higher-risk PCa while on active surveillance as the dependent variable. Demographic and lifestyle covariates were incorporated in the analysis to assess potential confounding and effect modification. RESULTS: Men from both hospitals presented with similar clinical and demographic characteristics. Total PA was inversely associated with odds of reclassification while on active surveillance (p-trend = 0.027). A weaker inverse association was observed with recreational PA (p-trend = 0.30). Men who participated in weekly vigorous PA were less likely to reclassify than those who did not (odds ratio (95% confidence interval): 0.42 (0.20-0.85)). CONCLUSIONS: Total and vigorous PA were inversely associated with odds of reclassification in two active surveillance cohorts. Given the limitations of this study, more robust prospective observational studies involving objective PA measures are warranted to confirm findings.
