Ultima Vez Modificado: 11 de septiembre del 2005
Dear OncoLink "Ask The Experts,"
My father is 76 yrs old and has bladder cancer. The family is concerned about the side effects of radiation therapy. I know the radiation may give him diarrhea & tiredness, but is urethral stricture & bowel adhesions a common side effect? Are there any other side effects we should be aware of while trying to make a decision about treatment?
Richard Whittington, MD, Associate Professor of Radiation Oncology at the University of Pennsylvania School of Medicine, responds:
Urethral strictures and bowel adhesions are both exuberant forms of scarring, and radiation does not necessarily cause a lot of this scarring, but rather potentiates it. In other words, radiation can make pre-existent scarring worse and can make subsequent injuries more prone to scar tissue than they would otherwise have developed. Urethral strictures are fortunately rare, occurring only 2-3% of the time, but they occur more frequently in men with a history of transurethral resection of the prostate, or men with prostatitis. It also can occur if a man passes a kidney stone later on, as this will scratch the wall of the urethra. It may even occur rarely from bruising from a cystoscopy (but you still need to have follow-up cystoscopies!) As for bowel adhesions, this also relates to prior bowel problems, including infections like diverticulitis, appendicitis (with rupture), and strangulated hernias. Otherwise, this is also rare, occurring about 2% of the time. Again, the radiation will make any future bowel surgery more difficult, and even if there are no adhesions now, there will most likely be some after surgery.
Other side effects are more frequent and are caused by scar tissue. Depending on how extensive the tumor is, when a man is treated with radiation and cisplatin, the tumor "falls off" and leaves an open bruise on the bladder wall that will heal slowly with time. This means 3-4 months of worsening urinary frequency, urgency, and nocturia. As the scarring occurs, the scar will contract. We see this with any scar. After the scab falls off, the scar is lumpy and red. A month later it is flat and pink. Six months after that, it pulls in on itself and turns white. As the scar contracts, the bladder wall gets stiffer and the bladder may get smaller, causing permanent frequency, urgency, and nocturia that varies in severity. There is also the risk of an ulcer in the front wall of the rectum that can cause pressure, (giving a sensation like you need to have a bowel movement), bleeding and pain. This occurs in 3 to 5% of men. It is treated with a cortisone enema and will heal over 6 to 9 months.
Your father is probably getting cisplatin (chemotherapy)and radiation. The response rate is 50 to 70% with the combination, but only 20% with radiation alone. See the Oncolink Rx information on Cisplatin for more information on its side effects.
Also, please note that I am not ignoring the women when I keep referring to men. Women rarely have urethral strictures for two main reasons: one, they do not have prostates, so they don't get prostatitis, and two, the female urethra is shorter and has a wider caliber. Also, rectal pain and inflammation is much less frequent in women because the uterus pushes the rectum away from the bladder, shielding it from the radiation.