Ten-year Mortality, Disease Progression, and Treatment-related Side Effects in Men with Localised Prostate Cancer from the ProtecT Randomised Controlled Trial According to Treatment Received

Background: The ProtecT trial reported intention-to-treat analysis of men with localised prostate cancer (PCa) randomly allocated to active monitoring (AM), radical prostatectomy, and external beam radiotherapy.

Objective: To determine report outcomes according to treatment received in men in randomised and treatment choice cohorts.

Design, setting, and participants: This study focuses on secondary care. Men with clinically localised prostate cancer at one of nine UK centres were invited to participate in the treatment trial comparing AM, radical prostatectomy, and radiotherapy.

Intervention: Two cohorts included 1643 men who agreed to be randomised; 997 declined randomisation and chose treatment.

Outcome measurements and statistical analysis: Health-related quality of life impacts on urinary, bowel, and sexual function were assessed using patient-reported outcome measures. Analysis was carried out based on treatment received for each cohort and on pooled estimates using meta-analysis. Differences were estimated with adjustment for known prognostic factors using propensity scores.

Results and limitations: According to treatment received, more men receiving AM died of PCa (AM 1.85%, surgery 0.67%, radiotherapy 0.73%), whilst this difference remained consistent with chance in the randomised cohort (p=0.08); stronger evidence was found in the exploratory analyses (randomised plus choice cohort) when AM was compared with the combined radical treatment group (p=0.003). There was also strong evidence that metastasis (AM 5.6%, surgery 2.4%, radiotherapy 2.7%) and disease progression (AM 20.35%, surgery 5.87%, radiotherapy 6.62%) were more common in the AM group. Compared with AM, there were higher risks of sexual dysfunction (95% at 6mo) and urinary incontinence (55% at 6mo) after surgery, and of sexual dysfunction (88% at 6mo) and bowel dysfunction (5% at 6mo) after radiotherapy. The key limitations are the potential for bias when comparing groups defined by treatment received and outdating of the interventions being evaluated during the lengthy follow-up required in trials of screen-detected PCa.

Conclusions: Analyses according to treatment received showed increased rates of disease-related events and lower rates of patient-reported harms in men managed by AM compared with men managed by radical treatment, and stronger evidence of greater PCa mortality in the AM group.

Patient summary: More than 90 out of every 100 men with localised prostate cancer do not die of prostate cancer within 10yr, irrespective of whether treatment is by means of monitoring, surgery, or radiotherapy. Side effects on sexual and bladder function are much better after active monitoring, but the risks of spreading of prostate cancer are more common.