Discussion
In patients undergoing RRP for PCa, it is critical to provide optimal
functional results as well as oncological control. The most important of
these are results related to continence and erectile function. Although
these results have been tried to be optimized in recent years with the
robotic platform that enables large and three-dimensional images, the
open retropubic technique still continues to be performed at a
considerable rate in the world.10
There is a consensus that the VUA technique is particularly important in
maintaining postoperative continence.11 In this study,
in which we analyzed the effect of these techniques on functional
results in patients who underwent two different VUA techniques in our
clinic, we revealed that although the continence results were better in
the 6-focal anostomosis group compared to the 4-focus group, it did not
have a significant effect on erectile function results. Our study
differs from previous studies by being the first to compare 4- and
6-focus VUA techniques head-to-head.
In a randomized controlled study in which the two techniques used in our
study were compared with the anostomosis technique performed with 2 U
sutures at 6 and 12 o’clock alignment, the number of sutures did not
affect the perioperative and postoperative parameters, but the VUA
duration was significantly shorter in patients operated with the
2-suture technique compared to the others 5. This
study is important as it is the first prospective study to focus on the
VUA technique during RRP. In our study, the duration of VUA was not
available, but the total operation times were similar between the two
groups. However, the conclusion, that the number of sutures did not
affect the continence results revealed in the previous study, was in
favor of the group in which the number of sutures was high in our study.
The factors that predispose to the development of VUA are not fully
understood. Anastomotic technique, previous endoscopic prostate surgery,
failure to obtain a watertight anastomosis resulting in urine
extravasation, excessive blood loss and excessive diathermy for
hemostasis of the bladder neck are the main
culprits.12 We hypothesize that the water-tight
anostomosis is more safely achieved in the six-focal anostomosis because
the suture line is denser and closer than the 4-focal technique, and
that better continence results are obtained as a result. As a result of
VUA performed with more frequent suturing, it is possible to expect that
foreign tissue penetrates the anostomosis line less and thus
mucosa-mucosa convergence is healthier. In a meta-analysis in which a
total of 9 studies including 1475 patients were evaluated, continuous
suturing and intermittent suturing were compared, and although
continuous suturing provided shorter catheterization time, anastomosis
time and a lower rate of extravasation, no significant difference was
found between continence rates and urethral stricture rates in the month
was 3, 6, and 12 and the duration of hospital stay between the two
techniques. It was underlined that the suture technique should be chosen
according to the surgeon’s experience and technical
approach.13 In another retrospective analysis, the
results of sutureless anostomosis in patients undergoing open and
laparoscopic radical prostatectomy were evaluated. In this VUA
technique, which is designed completely without sutures, the catheter
balloon was inflated and traction was applied. The authors observed a
significant rate of stricture (13.6%) while maintaining around 90%
continence rates in patients.7 Although this rate
underlines the importance of sutured VUA, uncertainties remain as to
which VUA technique is superior. Although the general opinion in the
literature is that the number of sutures does not affect the risk of VUA
and continence outcomes, there is consensus that a water-tight
anostomosis is vital to prevent urine extravasation.14,
15
During the operation, excessive blood loss and / or hematoma formation
may contribute to the development of VUA by negatively affecting tissue
healing by causing fibrosis and scar formation in the surrounding
tissue. The fact that the mean blood loss is similar in both groups
reveals that the effect of this factor is minimal in our patients. VUA
stricture development is an independent risk factor for the development
of postoperative incontinence.15 On the other hand,
prevention of anostomotic strictures is one of the most important
factors for continence recovery and also shortens the time required for
continence recovery.16 In our study, in the first
group with a higher stricture rate, the continence rates were found to
be lower in proportion to this outcome.
The application of oxidized cellulose sponges around the anastomotic
site can be used to block exudates and materials such as fluid or
cellular debris escaping from blood vessels. If urethral exudates
accumulate in the urethral cavity, it can lead to inflammation or even
infection of the urethra, jeopardizing healing.17 The
study using these materials provided slightly lower long-term
incontinence rates than ours.5 Cellulose sponges can
be effective agents in maintaining continence function. Some
modifications are recommended for use in VUA for optimum
postprostatectomic erectile function. One of these is that after
dissecting the anterior half of the urethra, four pre-placed sutures are
placed between 3 and 6 o’clock, and anostomotic sutures are placed on
the posterior half after the neurovascular bundle is separated from the
prostate apex.3, 18 Most of the patients in our group
consisted of patients with tumors limited to the prostate, and we
performed nerve-sparing prostatectomy in these patients. At the end of a
one-year follow-up, we achieved approximately 80% of erectile function
restoration and we concluded that the two VUA techniques we used did not
have a significant effect on erectile functions. For the preservation of
erectile function, the application of neuroprotective surgery is more
important than the VUA technique according to the risk assessment on
patient basis.
In our study, we found that, contrary to the literature, the VUA
technique affected both stricture development time and stricture rate.
We did not evaluate the preoperative voiding functions of the patients
with objective questionnaires. Not knowing the patients’ basal functions
can create confusion in comparing final functions, but preoperative
contience is not the only factor affecting this. Other reported risk
factors include patient age, disease stage, surgical technique,
surgeon’s experience, and previous endoscopic prostate surgery, and
there was no significant difference in these factors between the
groups.18
Our study has some important limitations. Since we do not know the
preoperative continence and erectile functions of the patients, we could
not analyze how much they changed according to basal levels in the
postoperative period. Surgery performed by different surgeons may cause
a surgeon selection bias, but this may be more consistent in that it is
a real-life picture of the situation in most reference centers.
Evaluating continence status with questions such as present / absent
instead of validated questionnaire forms might have overshadowed the
objective evaluation. On the other hand, in many studies in the
literature this function has been evaluated in this way. The main
strength of our study is that it is the first study to compare the
functional results of 4- and 6-focus VUA techniques, and obtaining
12-month restoration curves specific to the two functions appears to be
a valuable finding.
As a result, we found better continence results with 6-focus VUA than
with the 4-focus technique. There was no significant difference between
the two techniques in terms of other postoperative complications and
erectile function. Contrary to the general belief in the literature, the
number of anostomotic sutures in VUA may affect functional results and
may be decisive for surgeons who focus on functional results as well as
oncological results. Although the most important determining factor is
the surgeon’s habits and experience, the 6-focus VUA technique we
schematized in our study can be preferred due to its easy application
and similar operation time with the other technique. More consistent
results can be expected with prospective, randomized, controlled studies
with a higher number of cases.