Erectile Dysfunction Following Radical Prostatectomy, Prostate Cancer, Urinary Incontinence Following Surgical Procedure
Conditions
Keywords
robot-assisted radical prostatectomy, prehabilitation, rehabilitation, erectile dysfunction, urinary incontinence, PDE5 inhibitor, tadalafil, pelvic floor muscle training, prostate cancer, sexual rehabilitation, perioperative care, multimodal intervention
Brief summary
Prostate cancer is the most common cancer in Australian men. Robot-assisted radical prostatectomy (RARP) - surgical removal of the prostate - is a standard treatment, but it frequently causes erectile dysfunction (ED) and urinary incontinence that can persist for years and significantly affect quality of life. This trial (ROBOPREP) will test whether a multimodal program of prehabilitation (before surgery) and rehabilitation (after surgery) improves erectile function and urinary continence in men undergoing RARP, compared to standard care alone. The program includes four components, all delivered virtually and in a self-directed manner: 1. Pharmacological - tadalafil 5 mg once daily (a low-dose, TGA-approved erectile medication) beginning 4 weeks before surgery, paused during hospital admission, and resumed for 3 months following catheter removal after surgery. 2. Exercise - pelvic floor muscle training (3 sets per day) and aerobic exercise (40 minutes, 4 times per week) to strengthen the muscles and vascular supply involved in erectile and urinary function. 3. Nutrition - dietary guidance to support surgical recovery and vascular health. 4. Psychological/wellbeing - relaxation techniques, psychoeducation about expected recovery, and self-compassion strategies to address cancer-related anxiety. A total of 64 men will be recruited across three major Sydney hospitals (Royal Prince Alfred Hospital, Concord Repatriation General Hospital, and Chris O'Brien Lifehouse) and randomly assigned 1:1 to the multimodal program plus standard care, or to standard care alone. Outcomes - including erectile function (primary), urinary continence, quality of life, and psychological wellbeing - are assessed at baseline and at 6 weeks, 3, 6, and 12 months following surgery. All participant-facing elements of the program are digital, low-cost, and designed for real-world scalability.
Detailed description
The ROBOPREP Trial is a hybrid type 1 multicentre, assessor-blinded, parallel-group randomised controlled trial with nested qualitative and cost-effectiveness appraisal. The trial evaluates a virtually delivered, self-directed multimodal (p)rehabilitation program for men undergoing robot-assisted radical prostatectomy (RARP) for prostate cancer. Background: Erectile dysfunction (ED) occurs in 25-75% of men following RARP, with unassisted recovery of erectile function in only 20-25%. Urinary incontinence affects a further 27-40%. Current evidence supports early initiation of phosphodiesterase type 5 inhibitors (PDE5i), pelvic floor muscle training (PFMT), and psychological interventions, but no multimodal perioperative program combining all modalities has been evaluated in a rigorous RCT. Intervention: Participants randomised to the intervention arm receive, in addition to standard care: (1) tadalafil 5 mg/day orally commencing 4 weeks preoperatively, ceasing during hospital admission, and resuming for 3 months following postoperative catheter removal; (2) pelvic floor muscle training (3 sets/day: 20 fast and 20 slow contractions); (3) aerobic exercise (40 min, 4×/week, moderate-to-vigorous intensity); (4) nutritional guidance; and (5) psychological strategies including relaxation, psychoeducation, and self-compassion. Non-pharmacological components are delivered via a co-designed digital booklet and avatar videos. All components are self-directed to ensure scalability. Randomisation and Blinding: Randomisation (1:1, stratified by age ≤60 vs \>60 years, permuted blocks of size 2 and 4) is managed via a central secure REDCap randomisation module uploaded by an independent research officer. Outcome assessors are blinded to allocation; blinding of participants and treating clinicians is not feasible given the nature of the intervention. Statistical Analysis: Primary analysis is intention-to-treat. The primary outcome (IIEF-5 at 3 months postoperatively) will be compared between arms using Mann-Whitney U tests and multivariate regression adjusting for baseline characteristics. Secondary outcomes will be analysed using mixed models, Cox regression (time to continence), and chi-square or Fisher's exact tests as appropriate. The trial medication is funded by Generic Health (Lupin), who provide a donation covering participant reimbursement for tadalafil 5 mg (4-month supply; approx. AUD $120-150 per participant) and the TGA CTN application fee. Tadalafil 5 mg is TGA-approved for erectile dysfunction (ARTG: 289541).
Interventions
DRUGTadalafil 5 mg
Tadalafil 5 mg tablet, taken orally once daily. Commenced 4 weeks prior to surgery, ceased during hospital admission (3 days prior to surgery), and recommenced following postoperative urinary catheter removal (typically 5-10 days post-surgery) for 3 months. Total intended duration approximately 4 months. Supplied via standard prescription dispensing at community pharmacies (Generic Health brand). Reimbursement provided to participants via a cash card. TGA ARTG number: 289541.
BEHAVIORALPelvic Floor Muscle Training (PFMT)
Self-directed PFMT performed 3 sets per day. Each set comprises 20 fast contractions (1-second duration) and 20 slow contractions (10 seconds on, 10 seconds off). Adapted from Milios et al. (2020) using Continence Australia guidelines. Delivered via co-designed digital booklet and avatar instructional videos. Commenced 4 weeks preoperatively, continuing through 3 months postoperatively.
BEHAVIORALAerobic Exercise Program
Self-directed aerobic exercise at moderate-to-vigorous intensity (e.g., brisk walking while able to maintain conversation), 40 minutes per session, 4 sessions per week. Dose established by Gerbild et al. (2018). Delivered via digital booklet and avatar videos. Commenced 4 weeks preoperatively, continuing through 3 months postoperatively.
BEHAVIORALNutritional Recommendations
Structured dietary guidance addressing protein intake, fruit and vegetable consumption, wholegrains, healthy fats, hydration, and blood sugar control. Designed by a dietitian to support surgical healing, vascular health, and erectile and urinary function recovery. Delivered via digital booklet and avatar videos. Commenced 4 weeks preoperatively, continuing through 3 months postoperatively.
BEHAVIORALPsychological and Wellbeing Strategies
Self-directed psychological wellbeing program comprising: (1) relaxation techniques (progressive muscle relaxation, diaphragmatic/rectangle breathing, mindfulness/grounding); (2) psychoeducation on psychogenic erectile dysfunction, expected postoperative complications (ED, UI); (3) self-compassion and cognitive reframing strategies; (4) motivational interviewing-style elements to support adherence; (5) advice on social connection, smoking cessation, alcohol reduction, and sleep hygiene. Designed by a clinical psychologist and delivered via digital booklet and videos. Commenced 4 weeks preoperatively, continuing through 3 months postoperatively.
BEHAVIORALStandard Perioperative Care
Usual high-standard pre- and postoperative care delivered by the treating urological team, including clinical advice on exercise, nutrition, smoking cessation, alcohol reduction, expected surgical sequelae, pelvic floor exercises, blood sugar optimisation, medication review, and anaemia screening. Includes prostate cancer nurse specialist consultations and urology clinic follow-up.
Sponsors
Surgical Outcomes Research Centre (SOuRCe)
Generic Health
National Health and Medical Research Council, Australia
Sydney Local Health District
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Masking description
Due to the nature of the intervention, masking of participants and care providers is not possible. Outcome assessors are blinded to group allocation. Statistical analysis will also be performed blinded.
Intervention model description
Participants are assigned 1:1 to one of two parallel arms: (1) multimodal prehabilitation and rehabilitation program (plus standard care), or (2) standard care alone. Randomisation is stratified by age (≤60 vs \>60 years) using permuted blocks of size 2 and 4 via a central REDCap module.
Eligibility
Sex/Gender
MALE
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1. Adults aged ≥18 years undergoing elective robot-assisted radical prostatectomy (RARP) with curative intent for confirmed prostate cancer. 2. Consulting a urological surgeon with an appointment at participating sites at least 4 weeks prior to scheduled surgery. 3. Willingness to engage in prescribed self-directed interventions.
Exclusion criteria
1. Cognitive impairment such that they lack capacity to provide informed consent. 2. Currently taking intracavernosal injection therapy. 3. Severe or complete erectile dysfunction at baseline, defined as an IIEF-5 score ≤7 or self-reported absence of erectile function. 4. Prescribed nitrates or guanylate cyclase stimulators (e.g., riociguat) - pharmacological contraindication to PDE5 inhibitor use. 5. Impaired renal function (GFR \<50 mL/min and/or creatinine clearance \<30 mL/min). 6. Severe hepatic impairment or concurrent prescription of medications that inhibit CYP3A4. 7. Loss of vision in one eye due to non-arteritic anterior ischaemic optic neuropathy (NAION). 8. Myocardial infarction within the last 90 days. 9. Stroke within the last 6 months. 10. Unstable angina or angina occurring during sexual intercourse. 11. New York Heart Association (NYHA) Class II or greater heart failure in the last 6 months. 12. Uncontrolled arrhythmias, hypotension (\<90/50 mmHg), or uncontrolled hypertension. 13. Contraindications to participating in the prescribed exercise program. 14. No access to a device with internet connectivity.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Erectile Function - International Index of Erectile Function-5 (IIEF-5) | Assessed at 3 months postoperatively (primary endpoint). Also assessed at baseline (4 weeks preoperatively), 6 weeks, 6 months, and 12 months postoperatively. | The IIEF-5 is a validated 5-item self-report questionnaire assessing erectile function over the preceding 4 weeks. Scores range from 5 (severe erectile dysfunction) to 25 (no erectile dysfunction). A between-group difference of ≥4 points constitutes the minimal clinically important difference (MCID) as established by Rosen et al. (2011). The IIEF-5 is the abbreviated version of the 15-item IIEF, widely used in prostate cancer rehabilitation trials. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Urinary Incontinence - ICIQ-UI SF | Baseline (≥4 weeks preoperatively), 6 weeks, 3 months, 6 months, and 12 months postoperatively. | The International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF) is a validated 4-item patient-reported measure of urinary incontinence severity and impact on quality of life. Scores range from 0 (no incontinence) to 21 (severe incontinence). Assesses urinary leakage frequency, volume, and overall impact. |
| Number of Urinary Pads Used in 24 Hours | Baseline, 6 weeks, 3 months, 6 months, and 12 months postoperatively. | Total number of urinary pads used by the participant over a 24-hour period, as self-reported. A higher number of pads indicates greater urinary incontinence severity. |
| Weight of Urinary Pads Used in 24 Hours | Baseline, 6 weeks, 3 months, 6 months, and 12 months postoperatively. | Total weight (grams) of urinary pads used over a 24-hour period. Pad weight is obtained by weighing pads before and after use and calculating the difference. Higher weight indicates greater urine leakage volume. |
| Maximum Urinary Flow Rate (Uroflowmetry - Q-max) | Baseline, 6 weeks, 3 months, 6 months, and 12 months postoperatively. | Maximum urinary flow rate (mL/s) measured by uroflowmetry during voiding. Higher values indicate better bladder outflow function. |
| Post-Void Residual Urine Volume | Baseline, 6 weeks, 3 months, 6 months, and 12 months postoperatively. | Volume of urine remaining in the bladder after voiding (mL), measured by bladder ultrasound or catheterisation. Lower post-void residual volumes indicate more complete bladder emptying. |
| Maximum Detrusor Pressure (Urodynamics) | Baseline, 6 weeks, 3 months, 6 months, and 12 months postoperatively. | Maximum detrusor pressure (cmH₂O) measured during urodynamic testing, reflecting bladder contractility and outflow resistance during voiding. |
| Health-Related Quality of Life - Short Form-36 Health Survey, Version 2 (SF-36v2) | Baseline, 6 weeks, and 6 months postoperatively. | The Short Form-36 Health Survey, Version 2 (SF-36v2) is a validated 36-item multidimensional self-report questionnaire assessing health-related quality of life across eight domains: physical functioning, role limitations due to physical health, role limitations due to emotional health, bodily pain, general health perceptions, vitality, social functioning, and mental health. Each domain score ranges from 0 to 100, with higher scores indicating better health-related quality of life in that domain. Physical Component Summary (PCS) and Mental Component Summary (MCS) scores are derived (each ranging from 0 to 100; higher scores indicate better health). |
| Anxiety and Depression - Hospital Anxiety and Depression Scale (HADS) | Baseline, 6 weeks, 3 months, 6 months, and 12 months postoperatively. | The HADS is a validated 14-item self-report questionnaire with two 7-item subscales assessing anxiety (HADS-A) and depression (HADS-D) severity. Each subscale is scored 0-21; scores ≥8 indicate probable caseness. Designed for use in medical settings with somatic symptoms excluded to avoid confounding. |
| Fear of Cancer Recurrence - Single-Item Scale (FCR-1) | Baseline, 6 weeks, 3 months, 6 months, and 12 months postoperatively. | A single-item 0-10 numerical rating scale measuring fear of cancer recurrence. Scores range from 0 (no fear) to 10 (maximum fear of recurrence), with higher scores indicating greater fear of cancer recurrence. This single-item scale has been demonstrated as equivalently effective to the short-form FCR scale in oncological populations. |
| Pain Intensity - Numeric Pain Rating Scale (NPRS) | Baseline, 6 weeks, 3 months, 6 months, and 12 months postoperatively. | The NPRS is a single-item 0-10 scale measuring current pain intensity (0 = no pain, 10 = worst imaginable pain). Widely used in surgical and oncological populations. |
| Postoperative Complication Rate - Clavien-Dindo Classification of Surgical Complications | Within 30 days postoperatively. Complications also monitored at 6 weeks, 3 months, 6 months, and 12 months. | Proportion of participants developing postoperative surgical complications within 30 days of surgery, categorised under the Clavien-Dindo Classification of Surgical Complications. Grades range from I (minor complication requiring no specific treatment beyond standard medications) to V (death). Higher grades indicate more severe complications and represent a worse outcome. Assessed by the treating clinical team from medical records. |
| Length of Hospital Stay | At hospital discharge (postoperative), assessed up to approximately 5 days. | Total number of days from RARP surgery to hospital discharge, extracted from medical records. |
| Positive Surgical Margin Rate | Following surgical pathology report, assessed within approximately 4 weeks of surgery. | Proportion of participants with histopathologically confirmed positive surgical margins on surgical pathology report. A positive surgical margin indicates residual tumour at the resection edge and represents an adverse oncological outcome. |
| Pathological Staging - Tumour, Node, Metastasis (TNM) Classification | Following surgical pathology report, assessed within approximately 4 weeks of surgery. | Pathological TNM stage assigned from the surgical pathology report according to the Union for International Cancer Control (UICC) TNM classification system. Staging reflects the pathological extent of disease including primary tumour (T), regional lymph nodes (N), and distant metastases (M). Higher pathological stage indicates more locally advanced disease. |
| Tumour Grade - Gleason Score and International Society of Urological Pathology (ISUP) Grade Group | Following surgical pathology report, assessed within approximately 4 weeks of surgery. | Gleason score (range 6-10; higher scores indicate less differentiated, more aggressive tumour histology) and International Society of Urological Pathology (ISUP) Grade Group (range 1-5; higher grade groups indicate more aggressive disease and a worse prognosis). Both are derived from the surgical pathology report and are reported together as they describe the same histopathological characteristic. |
| Adverse Pathological Features: Seminal Vesicle Invasion, Perineural Invasion, and Extraprostatic Extension | Following surgical pathology report, assessed within approximately 4 weeks of surgery. | Proportion of participants with each of the following adverse pathological features identified on surgical pathology report: (1) seminal vesicle invasion (SVI - yes/no), (2) perineural invasion (PNI - yes/no), and (3) extraprostatic extension (EPE - yes/no). Each is reported as a proportion (%). Presence of these features indicates more locally advanced pathology and is associated with poorer oncological outcomes. |
| Incremental Cost-Effectiveness - Cost per IIEF-5 Improvement | At 6 months postoperatively. | Economic analysis estimating the incremental cost per point improvement in IIEF-5 score for the multimodal program versus standard care. Costing data will include inpatient hospitalisation costs (from SLHD Performance Unit), out-of-pocket participant costs (reimbursed medication), and research-related resource utilisation. |
| Implementation Evaluation - RE-AIM Framework | At trial completion (approximately 6 months postoperative of final participant). | The RE-AIM (Reach, Effectiveness, Adoption, Implementation, Maintenance) framework will be applied by investigators to evaluate the implementation of the trial, including reach of the eligible population, fidelity of intervention delivery, and potential for future adoption in clinical settings. Assessed via a structured investigator-completed survey. |
| Acceptability of the Multimodal Program to Participants | Following completion of the prehabilitation program, assessed at approximately 3 months postoperatively. | Assessed via a structured qualitative survey (Likert-scale and open-ended questions) and semi-structured interviews with intervention arm participants. Explores barriers and facilitators to engagement, satisfaction with the program, and experiences with pharmacological adherence including pharmacy logistics. Qualitative free-text data will be analysed using reflexive thematic analysis. This is a qualitative outcome and is not scored on a numerical scale. |
Countries
Australia
Contacts
CONTACTNicholas Hirst
CONTACTSOuRCe Admin
PRINCIPAL_INVESTIGATORDaniel Steffens
Surgical Outcomes Research Centre (SOuRCe)
Outcome results
None listed