Sexual dysfunction is a common side effect of medical and surgical treatments for rectal
cancer. It can manifest as ejaculation disorders or erectile dysfunction. Due to the
modesty of both patients and doctors, these disorders are poorly understood and probably
underestimated at present. After surgical treatment alone, sexual dysfunction can be
observed in 40 to 90% of patients, depending on the studies and the technique used. It is
the result of direct vascular and nerve damage caused during surgery. It occurs
immediately after surgery. It can sometimes recover over time, up to 18 months after the
operation. Pelvic radiotherapy also has side effects on sexual function. The damage is
caused by alterations in microvascularization or direct nerve damage.
It develops more gradually, over a period of several weeks or months. After treatment
combining radiotherapy and surgery, the risk of sexual dysfunction is significant and can
affect up to 90% of patients.
In an attempt to improve these results, surgical techniques have gradually evolved
towards complete resection of the mesorectum with nerve preservation. Studies published
on this subject show an improvement in functional outcomes, without any deterioration in
oncological outcomes. This has now become the standard surgical technique.
In the specific case of the management of neoplastic disease, it is common to observe a
reactive anxiety-depression syndrome in patients. This mood disorder affects libido and
sexuality. A lack of sexual activity in the postoperative period is therefore not
necessarily related to iatrogenic vascular-nerve damage. In order to improve patients'
quality of life, it is useful to know how to objectively diagnose post-operative erectile
dysfunction. This diagnosis should make it possible to distinguish between disorders
related to vascular-nervous damage and those that are part of a post-operative
anxiety-depression syndrome.
An accurate diagnosis of sexual dysfunction can lead to specific treatment:
intracavernosal injections of prostaglandins are the standard treatment, but
phosphodiesterase 5 inhibitors can also be used. For these reasons, it is necessary to
develop a method for evaluating objective erectile dysfunction after resection.
The Rigiscan Plus device is a commercially available measurement tool that has received
CE certification.
It can be used to assess several parameters of erection: rigidity, intensity, and
duration. This measuring device has been validated for the assessment of erectile
dysfunction, and normal values have been established in healthy subjects.
Combining these two tests makes it possible to assess the presence or absence of
erections during REM sleep and to objectively diagnose erectile dysfunction:
in the presence of decreased libido, nocturnal erections are preserved, whereas they are
impaired following vascular-nervous damage. Recording nocturnal erections is useful for
assessing erectile dysfunction after rectal surgery in two ways. Preoperatively, it
provides objective confirmation that the patient has spontaneous erections of good
quality. Postoperatively, recording allows confirmation that the autonomic nervous system
required for erection has been preserved. It is an objective examination that is
independent of the patient's libido, which is often impaired by the treatment of a
neoplastic disease.
