Hypothesis / aims of study
Stress Urinary Incontinence (SUI) following radical prostatectomy(RP) persists despite the improvement of surgical techniques (1) and it is one of the main concerns for patients who undergo this procedure.
Many factors are involved: sphincteric dysfunction after RP (among others direct injury to the sphincter or its inervation, shortening of the membranous urethra, sphincter complex displacement), bladder dysfunction or changes in the pelvic floor among others. The functional recovery of the all anatomical mechanisms involved causes continence is progressively restored within 12-24 months to years after surgery. However, this period of time (recovery period) greatly alters the patient's quality of life.
Many authors reports that there is little recovery in urinary continence beyond 12–24m after RP (established incontinence period) (2). However, Lee et al publish that many RP patients continue to recover urinary continence after 12 months postopertive and the level of functional recovery by 12 months is associated with long-term recovery (3). At far, in these studies urinary continence was assessed using a questionnaire administered or pad count. However, pad test can provide additional information about degree of incontinence.
The aims of this study is to assess our data for this period (first-second year), based on the quantification of the 24-hour pad test (PT24h).
Study design, materials and methods
Inclusion period: patients had undergone an open retropubic or laparoscopic RP from April 2011 to June 2016.
Patients included: patients with two years of follow-up after radical prostatectomy with PT24h≠ 0 at first year follow-up and not eligible for male incontinence surgery.
Exclusion criteria: previous external beam radiotherapy, brachytherapy or prostate cancer focal therapy. Postoperative complications. Salvage radiotherapy.Loss to follow-up.
Functional Follow-up after radical prostatectomy: all patients perform a Pelvic Floor Muscle Training program (it starts three weeks before RP). Degree of incontinence was assessed with a 24-Hour Pad test and the Spanish validated version of International Consultation on Incontinence Questionnaire-Short Form (ICIQ-UI SF). Continence was evaluated at first and sixth weeks after RP, third and sixth month and after one (1st year PT) and two years of follow-up(2nd year PT).
Statistical analysis: descriptive statistics and confidence interval of a mean, t test to compare two means and Spaghetti plot.
Figure 1 shows the flow-chart of patients during the study. The final study group corresponded to 114 patients with the first postoperative year PT24h≠0 (1st year PT). There were no significant differences between 1st year PT (median 24g, range 2-1500) and the second year (median 20.5g, range 0-1630) (p=0.97).
At the end of the second year follow-up (2nd year PT), 100 patients had a PT=0 and 14 had a PT≠0. In the first group (2nd year PT=0), the median 1st year PT was 14g(range 2-145) and in the second group (2nd year PT≠0) the median 1st year PT was 26 g (range 2-1500) (p=0.213). Considering the rank of the fist group (2-145g), a Spaghetti plot was desing (figure 2).
The percentage of patients with 2nd year PT =0 according to 1st year PT was:
1st year PT <20g (47 patients): 9 patients with 2nd year PT =0 (19%)
1st year PT 20-50g (35 patients): 3 patients with 2nd year PT =0 (8.6%)
1st year PT >50g (32 patients): 2 patients with 2nd year PT =0 (6%)
No patients with 1st year PT >150 g (n=17) had 2nd year PT =0.
Interpretation of results
This work has two strengths in relation to other studies that evaluate postoperative continence in radical prostatectomy: degree of incontinence was quantitative assessed (24h PT) and all patients have a closed follow-up, with 6 pad test measurements.
According to the previous literature, in our study the probability of improvement of continence after 12 months postoperatively is low.
With the consensus of the patient, it is feasible to indicate an incontinence surgery with a fIrst year PT >50g, taking into account the greatly alters the patient's quality of life