PROstate cancer follow-up care in Secondary and Primary hEalth Care: PROSPEC study.

This study will compare specialist-based (usual care) versus general practitioner-based (intervention) follow-up care of prostate cancer survivors who have completed primary treatment (prostatectomy or radiotherapy) for localized prostate cancer. Eligible men will be randomised (1:1) to the current hospital follow-up care (N=195) or intervention (N=195), and will be followed during a two-year study period. The two arms will be compared in terms of adherence to the prostate cancer surveillance guidelines, the time from a biochemical recurrence to retreatment decision-making, the management of treatment-related side effects, health-related quality of life, anxiety, continuity of care, and cost-effectiveness. The outcome measures will be assessed at randomisation (3 months after treatment), and at 12, 18, and 24 months after treatment.

1. The level of adherence to the prostate cancer surveillance guideline will not differ significantly between GP-led and specialist-led survivorship care.

2. GP-led survivorship care will be more cost-effective than specialist-led survivorship care.

Primary outcome: non-inferiority study. We expect that 90% of the patients in the usual care group will be treated in adherence with the guideline, defined as 4 PSA measurements in the study period of 2 years. This is in line with the observed adherence to PSA testing recommendations in a previous randomized controlled trial of shared care for follow-up of men with prostate cancer. We consider an adherence percentage as low as 80% in the experimental group (follow-up by GP) as acceptable and lower adherence percentages as unacceptable.



Secondary outcomes:

(1) The time from a BCR to prostate cancer retreatment decision-making. This is defined as the time from any detectable PSA level after surgery (>0.1 ng/mL) with or without radiotherapy or a rising PSA level of 2 ng/mL over the post-treatment nadir after radiotherapy without surgery to the decision of prostate cancer retreatment. Despite the current discussion on the cut-off value of 2 ng/mL after radiotherapy without surgery, we choose this value since there is no evidence on a better prognosis of the patient when you act before a PSA level of 2 ng/mL.



Scores for the APECC, EORTC QLQ-C30 and QLQ-PR25, MAX-PC, NCQ, EQ-5D-5L questionnaires will be calculated according to published scoring algorithms. Effect sizes of 0.2 are considered small, 0.5 moderate, and 0.8 large. Effect sizes of approximately 0.5 are considered to be clinically relevant. A 2-sided P value < 0.05 will be considered to be statistically significant for the overall model. The P value for specific contrasts will be set at <0.01, lowering the risk of type 1 errors due to multiple testing. Nevertheless, in all appropriate cases 95% confidence intervals will be given.

The intervention is based on a primary care model where prostate cancer survivors will be referred to their GP for follow-up and aftercare after the first follow-up visit at the hospital. All patients will receive follow-up care according to the current prostate cancer surveillance practice.