Thursday, November 19, 2015
Urinary incontinence after prostate cancer treatment is a fairly common complication known to cause significant distress. Fortunately, although many men suffer from urinary incontinence immediately after radical prostatectomy (RP) — more than 50 percent are incontinent at one month post-RP — the condition generally resolves with time, and few men still suffer from incontinence one year after surgery. A prospective evaluation of patients after RP showed that 87 percent needed no urinary incontinence pads one year after surgery, increasing to 93 percent at two years after surgery. (1) Very few men experience urinary incontinence after primary radiation therapy; however, the likelihood that this complication will occur increases dramatically if patients then undergo a transurethral resection of the prostate (TURP), with approximately 18 percent of these men reporting urinary incontinence. (2)
A number of investigators have identified risk factors related to urinary incontinence after RP including age, body mass index (BMI), comorbid conditions, and membranous urethral length. These findings led Memorial Sloan Kettering investigators to develop a predictive model that determines the risk for urinary incontinence based on these factors. (3) The model is useful for identifying the small number of patients who are at high risk for long-term urinary incontinence after RP, and who may benefit from the use of intraoperative maneuvers designed to decrease incontinence.
Short-term urinary incontinence after RP generally resolves in a predictable way, with improvement in nighttime incontinence first, followed by improvement in daytime incontinence. Patients who had experienced preoperative urinary symptoms predictably report dramatic improvement in their symptoms. If the usual pattern of improvement in urinary symptoms and incontinence does not occur, patients should be assessed further or referred to a specialist in voiding dysfunction.
Pelvic floor muscle exercises (Kegel exercises) and other rehabilitation exercises can hasten the return of continence after RP, and help to improve continence in men with persistent urinary incontinence. (4) Despite these efforts, approximately 10 to 15 percent of patients will continue to have bothersome urinary incontinence one year after RP, and about half will seek treatment for it.
A Range of Treatments for Urinary Incontinence
If conservative treatment measures such as bladder training and pelvic floor muscle exercises fail to improve urinary continence, further investigation is warranted. Patients who suffer from urge urinary incontinence, have overactive bladder symptoms, or have detrusor overactivity on urodynamics testing usually receive first-line pharmacologic treatment in the form of an anticholinergic or a beta-3 adrenergic agonist. In men whose symptoms progress or who do not respond to this treatment, botulinum toxin injections or neuromodulation can be tried. (5) Men who have undergone RP, however, are more likely to suffer from stress urinary incontinence, in which case options for medical therapy are limited. Duloxetine, a serotonin and norepinephrine reuptake inhibitor (SNRI), is used to treat stress urinary incontinence in Europe and Japan, but the drug has not been approved for this indication in the US.
Surgical therapy is the mainstay of treatment for male stress urinary incontinence. Three general types of surgical interventions are available: endoscopic urethral injections, male slings, and artificial urinary sphincter (AUS). (6) Urethral injection of collagen or synthetic material is a common treatment in the US, but it generally does not provide lasting results. (7) However, male slings and AUS both provide durable improvements in continence for men with stress urinary incontinence. (8)
Determining which patient will have a better outcome with the male sling versus AUS is an area of active study at MSK. We tend to place slings in patients with no history of radiotherapy or stricture disease, and in those who are experiencing relatively less severe incontinence. The AUS, considered by most authorities to be the gold standard treatment for male incontinence, can be used in all other patients with bothersome stress urinary incontinence.
More than half the AUS procedures at MSK are performed in men who had radiation therapy in the past, with a large number of them having also undergone salvage prostatectomy (RP after failed primary radiation therapy). AUS surgery in these patients requires meticulous operative technique, the use of technical modifications to limit rates of AUS cuff erosion, and judicious use of patient education materials prior to and after the operation. The high volume of male continence surgery performed at MSK contributes to improved postoperative outcomes and a decreased need for reoperations. (9)
Both male slings and AUS procedures have long-term complications, the rates of which increase as the time from surgery increases. Male sling explantation for infection and AUS placement after sling failure are performed routinely at MSK. Precise knowledge of anatomy and the details of the previous operation are critically important because dissection can be hampered by the inflammatory response.
AUS explantation for infection or erosion and AUS replacement surgeries are being performed in increasing numbers, particularly in men who had an AUS placed many years ago and who experienced subsequent malfunctioning of the device. We follow a straightforward algorithm for managing device failure that includes pelvic imaging and cystoscopy. (10) In addition to standard surgical replacement techniques, we have introduced new methods for managing difficult complications such as recurrent anastomotic stricture after AUS placement. (11)
The surgical expertise at MSK has led to lower rates of urinary incontinence after RP. We continue to increase our understanding of the risk factors for urinary incontinence, and to conduct significant research into predictive models, novel surgical techniques, and new ways to manage complications after surgical correction of male stress urinary incontinence.