Sexual Dysfunction After Prostate Cancer
Introduction[edit | edit source]
Normal sexual function in men relies on the complex interaction between biological, emotional, cognitive, behavioural, contextual and interpersonal factors. (8)
There are multiple physiological processes involved in male sexual function such as sexual desire (libido), erectile functioning, ejaculation and orgasmic ability and quality
Sexual Function in Men[edit | edit source]
Sexual desire relies on a variety of factors both physical and psychological. Testosterone levels play an important role in physiological libido (6)
Erectile function forms an important part of a man’s sexual function. But it is only a part of the picture. A normal erection depends on a sequence of physiological, neural, vascular, metabolic and endocrine events (Hackett et al., 2018). There are different types of erections; reflexogenic, psychogenic and nocturnal. Reflexogenic erections occur when the penis is physically stimulated and psychogenic erections from other stimulation such as visual, auditory or psychological inputs. Nocturnal erections occur in men every night with about 5-8 per night and can last up to 30 minutes each. Erectile dysfunction (ED) is a component of male sexual dysfunction and can be defined as the persistent inability to achieve or maintain an erection firm enough or lasting long enough to participate in sexual activities (Hackett et al., 2018) Problems with erectile function can come from physical and psychological problems. When a man’s nocturnal erections stop it can be used as a diagnostic factor in determining a physical cause of the erectile dysfunction. (REF?)(Salonia vol 22004). The pelvic floor muscles, in particular, the bulbospongiosus and ischiocavernosus, play an important role in penile rigidity and injury or weakness can play a role in erectile dysfunction (16).
The prostate is responsible for the production of seminal fluid which makes up the majority of the ejaculate. When the prostate is removed or affected by radiation there is often a significant loss or absence of ejaculate (6) Ejaculation occurs when the smooth muscle of the prostate contract and the urethra smooth muscles relax to allow the ejaculate to enter the urethra. Thereafter a strong involuntary contraction of the bulbospongiosus expels the ejaculate (16).
Orgasm is still something that is not completely understood. It is mediated by the autonomic nervous system but there is also cortical involvement (17). The pelvic floor muscles play an important role in orgasm. Damage to the nerves and spasm of the muscles can play a role in the orgasmic dysfunction (6)
Sexual Dysfunction after Prostate Cancer Treatment[edit | edit source]
Early Prostate Cancer (PCa) treatment (surgery or any form of radiotherapy whether external beam radiotherapy or brachytherapy), has the unfortunate side effect of sexual dysfunction. Other common side effects could include pain and incontinence (A. U. Frey, Sonksen, & Fode, 2014). While most men recover from pain and incontinence after PCa surgery, they often live with long-lasting and debilitating sexual dysfunction that remains untreated and unresolved (A. U. Frey et al., 2014).
Male sexual dysfunction may present as one or a combination of the following conditions: (Hatzimouratidis & Hatzichristou, 2007).
- Sexual interest dysfunctions
- Sexual arousal dysfunctions
- Erectile Dysfunction(ED)
- Premature/rapid/early or delayed ejaculation
- Anejaculation
- Orgasmic dysfunction
- Sexual aversion disorder
- Priapism (prolonged erection of the penis)
- Peyronie’s disease (a painful curvature of the penis)
- Sexual Dysfunction after Radical Prostatectomy
Prostate Cancer Surgery, specifically a radical prostatectomy is commonly used as a curative measure to treat prostate cancer, and surgeons aim to retain urinary continence and sexual function during the procedure of removing the prostate (Trinh et al., 2013) (Heidenreich et al., 2011). A radical prostatectomy however, remains a challenging urologic procedure because the prostate is in close proximity to the bladder, rectum, and neurovascular supply to the penis. An adequate resection of the prostate without damaging surrounding tissue presents trades off between cancer control and preservation of functional outcomes such as continence and potency (Wennberg, Roos, Sola, Schori, & Jaffe, 1987).
A study conducted found that 98-100% of men who had undergone RP surgery will have initial incontinence and impotence and an alarming 70% of these men will not recover from their initial ED (Christian J. Nelson, Deveci, Stasi, Scardino, & Mulhall, 2010)
The European Association of Urology recommends that a nerve-sparing procedure is the recommended route for surgeons to use on men with normal preoperative erectile function (Heidenreich et al., 2011). Despite meticulous dissection in an attempt to preserve the neurovascular bundle during a radical prostatectomy, there is evidence that neurapraxia, hypoxic nerve insults, fibrosis, and apoptosis of cavernous smooth muscle affect sexual function and create drastic effects on patients’ experience and sexual satisfaction (Clavell-Hernandez & Wang, 2017)s
There are a number of different surgical approaches and depending on the approach used, the extent of the cancer, as well as the skill of the surgeon erectile dysfunction post prostatectomy ranges from 14%-90% (1) (14)
Sexual Dysfunction after Non-Surgical Treatment for Prostate Cancer[edit | edit source]
A 2017 study found that erectile dysfunction (ED) was common regardless of the treatment modality (surgical or non-surgical) used for PCa. ED reportedly also increased during each year of follow-up after initial surgical or non-surgical intervention, while it was reported in approximately 50% of patients within a 5-year period after receiving their intervention to treat PCa (Gaither et al., 2017)..
Men who have undergone hormone deprivation treatment as a management strategy for Prostate Cancer will have lowered or absent testosterone levels. This will negatively affect their sexual desire or libido (6)
The Neglected Sexual Side Effects after Prostate Cancer Treatment
With a research field full of data on general sexual dysfunction, there still remains a host of sexual dysfunction side effects after early stage prostate treatment that are being neglected and left untreated by medical professionals. Most literature to date focuses on erectile functioning but this is one component of male sexual function and problems related to sexual desire, ejaculation and orgasm have been neglected. These conditions may include orgasm-associated incontinence (OAI), urinary incontinence in relation to sexual stimulation (UISS), altered perception of orgasm, orgasm associated pain (OAP), penile shortening (PS), and penile deformity (A. S. Frey, J.: Jakobsen, H.: Fode, M., 2014; A. U. Frey et al., 2014; Salonia et al., 2017b) .These conditions are collectively referred to as the “neglected sexual side effects”. Frey et al 2014 reported in their systematic review of post prostatectomy patients that OAI and UISS are experienced by 20–93% of RP patients, orgasmic function was altered in 80% of patients, OAP was experienced by 3-19% of patients and PS occurred in 15–68% of patients (A. U. Frey et al., 2014).
Quality of Life[edit | edit source]
Sexual function has been identified as the quality of life domain most strongly associated with outcome satisfaction after treatment for prostate cancer (Sanda et al., 2008). (12) Amidst multiple physical and psychosocial factors, erectile function has been shown to be an independent predictor of both bother and depression in men after radical prostatectomy (12) (C. J. Nelson, Choi, Mulhall, & Roth, 2007). Sexual function is inversely associated with depressive symptoms in patients treated for prostate cancer 12 (Roberts, Lepore, Hanlon, & Helgeson, 2010). This association remains evident for at least four years after the diagnosis of prostate cancer, even after correction for possible confounders (C. J. Nelson, Mulhall, & Roth, 2011).
