Madrid, July 8 2019:- One of the main side effects of surgical or radiotherapy treatments in patients with gynecologic cancers, like ovarian or uterine tumors, is urethral stenosis; that is, a narrowing of the urethra, the tube through which urine passes from the kidney to the bladder. When this conduct narrows, urine cannot be emptied properly, accumulating in the kidney and can lead to renal insufficiency.
For cancer patients, renal insufficiency can mean they do not get the full dose of chemotherapy needed to fight their disease, making the treatment less effective. “As the kidney does not work properly, the patient cannot eliminate all the chemotherapy agent, so the dose must be reduced to avoid toxicity”, points out Dr. Fernando Lista, head of the Endourology Section at MD Anderson Cancer Center Madrid.
To prevent this, cancer patients are usually fitted with a Double J stent, a device that comes into contact with both the kidney and the bladder and, as a result, can sometimes cause blood urine and intense pain”, explains Dr. Lista.
To deal with these symptoms, which seriously affect the patient’s quality of life, Dr. Lista describes an alternative treatment - “placing a stent (a kind of coil) inside the urethra, just like inserting a stent in the heart to prevent heart attacks”. In fact, the mechanism and aim of both types of stent is the same – to expand and dilate the area to let blood or urine flow more easily”.
Another advantage of using the ureteral stent instead of the Double J stent is that once implanted, it does not need to be changed. On the other hand, the Double J stent must be changed every 6-8 months, depending on the type of patient and degree of stenosis.
Because of its significant advantages, the procedure is already being used on patients with congenital urethral stenosis, but had not been used on cancer patients until now. “There were doubts about whether the stent would be as effective in cancer patients with urethral stenosis caused by surgery and radiotherapy as in patients with congenital stenosis, but the results in clinical practice have been very promising”, states Dr. Lista.
So, it is very good news for cancer patients, since they no longer have to submit to surgery periodically to replace the Double J stent, with the obvious advantage of not having to go to hospital for people who spend a good deal of their lives in hospital. Furthermore, Dr. Lista points out that “to set up surgery for a cancer patient, you have to make sure the patient does not have chemotherapy planned, that his/her defenses are not compromised at the time, etc., all of which complicate things even more.” In the case of a cancer patient who already has a Double J stent implanted, this can be replaced with a ureteral stent very simply.
Cancer and urethral stenosis
Surgery and radiotherapy are the main causes of urethral stenosis, or stricture, in cancer patients, although it can also be the result of pressure caused by a tumor in the urethra, as in the case of retroperitoneal lymphoma. In the case of surgery, explains Dr. Lista, the problem is scarring. “Because the urethra is such a fine tube, tissue scarring after surgery can cause fibrosis, leading to stenosis, making the tube rigid and unable to function correctly”.
In the case of radiotherapy, stenosis is caused by premature aging of the tissue in the area treated. “When tissue is radiated, it ages prematurely and becomes more fibrous, harder, losing elasticity as if going from 20 to 40 years in age”, explains the doctor, who goes on to point out that the problem is quite common in cancer patients over time.