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Side Effects Vary Between Therapies

All radiation techniques have similar side effects, though the degree varies between each form of therapy.


There is a silver dollar size area of bladder and a silver dollar size area of rectum that is closely adhered to the prostate. These areas receive“sunburn” from the radiation.  All forms of radiation give a dose to these small areas. However, some treatments have a larger area of bladder and rectum receiving the radiation and some treatments deliver more radiation to these areas. The size of these radiated areas and the dose of radiation those areas receive determine the side effects. Our “real time” radioactive implant technique constantly calculates the dose to the rectum and bladder during the procedure while calculating the location of each seed.


Factors that increase side effects regardless of dose of radiation include:

  • Ischemia from atherosclerosis and/or smoking
  • Prior pelvic surgery
  • Diabetes
  • Degree of pre radiation urinary or bowel symptoms
  • Inflammatory bowel disease

Genitourinary side effects:

  • Dysuria (burning on urination)
  • Frequency/urgency, nocturia (getting up at night to void)
  • Incontinence
  • Retention or urine
  • Hematuria

Dysuria: Burning on urination can occur immediately after the implant or later – usually occurs during the completion of the IMRT/IGRT. Medications are effective in controlling dysuria.

Frequency/urgency/nocturia: These symptoms are similar in that they are from the bladder irritation. Numerous overactive bladder medications and medications to relax the prostate are used to control these symptoms. Most patients have resolution of these symptoms over time. At 6 months after implant, about half of our patients are off medications. At one year after radiation only a quarter of our patients are using medications to control these symptoms. About 10% of our patients use the medications for periods over a year.

Incontinence: Brachytherapy at our center has had less than a 2% incidence of incontinence. The incontinence after brachytherapy is different from the incontinence after surgery. After surgery, incontinence usually occurs from a weak urinary sphincter and the urine escapes with movement of the body (stress urinary incontinence). With brachytherapy, the incontinence is an urgency type, where the urge to void is strong and a small amount of urine escapes before the patient can get to a toilet. The degree of this incontinence varies tremendously between patients and most patients have it infrequently during the day and not daily.

Urinary Retention: One in 20 patients can have retention immediately after the radioactive seed implant. Late retention or long term retention is uncommon. Management is usually medical using alpha blockers (Flomax, Terazosin, Tamsulosin, Uroxatral, and Rapaflo) and 5-alpha reductase inhibitors (Proscar, Finesteride, and Avodart) or Androgen Deprivation injections (Lupron, Eligard, Zoladex, and Firmagon. The alpha blockers reduce the prostate muscle tone making the prostate easier to open when voiding. The 5-alpha reductase inhibitors reduce the size of the gland. The Androgen deprivation injections reduce the size of the prostate. Rarely is surgery required for retention.

Hematuria: This is a rare complication and usually occurs many months to several years after the implant or radiation. The bleeding can be controlled with medications and on occasion, hyperbaric oxygen therapy (HBOT). Hyperbaric oxygen therapy uses oxygen in a pressurized chamber used for treating patients with ‘The Bends’ (deepwater diving decompression sickness).  We use hyperbaric oxygen therapy over a 2 to 6 week daily treatment regimen. The treatments work by inducing the growth of new blood vessels to revascularize the tissue and relieve ischemia (localized restriction of blood flow).

Gastrointestinal (GI) Side effects: The radiation to the pelvic area is not associated with nausea and diarrhea. Most patients have no GI side effects. About 5% of patients experience increased urge to have a bowel movement. Most patients have the side effects limited to the time around finishing therapy. Medications work well to control these symptoms. For persistent problems or blood in the stool, we have worked with Gastroenterologists in controlling symptoms. Hyperbaric oxygen therapy has been very effective in managing radiation side effects. GI system radiation side effects are common to all forms of radiation and are least in the Iodine monotherapy or combination palladium plus IMRT/IGRT.

Erectile dysfunction: Erectile function is always different with any form of therapy for prostate cancer. Common to all treatments is loss of semen. Orgasm can occur without semen emission. In surgery, the vas deferens from the testes are disconnected from the prostate. Most of the fluid in the ejaculation is from the seminal vesicles, which are large sacks of fluid that sit above the prostate, behind the bladder and in front of the rectum. Some of our seed implant patients have preserved small amounts of ejaculation but this is not predictable and therefore, never promised. 

Other ways the erections are different after surgery and radiation is loss of rigidity. The seed implant procedures  affect the rigidity less than any other form of radiation and much less than surgery.  Many of our patients are very little changed after the radiation. Radiation alone is not usually responsible for loss of erectile function. Usually illnesses, including hypertension and diabetes with the medications used for treatment, contribute to erectile dysfunction. Adding radiation is one more "straw on the camel's back".

Factors that aggravate erectile dysfunction include:

  • Diabetes
  • Hypertension
  • Medications
  • Smoking
  • Prior Surgery
  • Sleep Apnea