It is often a shock when the diagnosis of cancer is made, especially when the news is unexpected. Often times with prostate cancer the diagnosis is made before symptoms are present. This is due to the ability to diagnose prostate cancer at an early stage with the PSA blood test, digital rectal examination and ultrasound guided biopsy (removal of a small amount of tissue to be looked at under the microscope to determine if cancer cells are present). Often times symptoms of difficulty with urination or getting up often at night have been present for many years and are unrelated to the cancer. The earlier diagnosis often makes it possible to achieve a cure with minimal or no adverse effect on quality of life.
The following information concerning the diagnostic process, treatment options, and side-effects is presented to familiarize you with what you may experience over the next few months.
PSA stands for prostatic specific antigen. It is a substance produced by the prostate gland. A normal value is between 0 and 4.0 ng/mL. An elevation above 4 or an unexpected change (for example; a PSA running 1.0 for several years which rises to 3.5 within a year), may prompt an ultrasound guided biopsy. The ultrasound probe placed in the rectum bounces sound waves off the prostate enabling the urologist to specify the areas of biopsy. Usually 6 areas of the prostate are biopsied along with any additional biopsies of suspicious areas. When prostate cancer cells are found, the pathologist assigns a "Gleason score" which is an indication of how aggressive the cancer looks under the microscope. These numbers run from 2 to 10 with 10 being the most aggressive.
At times a bone scan is done to check for possible distant spread to the bones. It is the most sensitive test we have, although like any other test, it is not 100 percent accurate. If all of the diagnostic work up indicates that the cancer is confined to the prostate then options for treatment for cure include surgery or radiation therapy. Even when the work up indicates the cancer is confined to the prostate there is still a chance there could be microscopic (not seen on ultrasound, CAT scan, MRI, etc.) spread present outside the prostate gland. In the surgical literature, when the cancer was felt to be confined to the prostate, small cancer cells growing in tentacles outside the fibrous capsule (coating) of the prostate occurs in 25 to 50% of patients. As radiation oncologists, it is important for us to have an idea of what the risk of the microscopic spread outside the prostate gland is. This helps us determine which treatment options to recommend.
Two types of radiation are available for early prostate cancer:
The probability of having microscopic cancer cells growing outside of the capsule of the prostate gland is expressed in a formula developed from research at Johns Hopkins University and later confirmed at University of California San Francisco. The formula, known as the Roach formula, named after the physician who developed it (not the insect), is the Gleason score (minus 3 times 10) plus (1.5 times) the PSA. For example, with a Gleason score of 6 and a PSA of 8; (6 - 3) x 10 = 30 plus (1.5 x 8) = 12 which gives a total percent chance of microscopic spread outside the prostate gland of 30 + 12 = 42 percent. There is still a chance for cure with this type of spread; it is different than distant spread to other parts of the body, but it often requires a combination of external beam and radioactive seed implant.
Another major advancement in the fight against prostate cancer is the temporary use of hormonal treatments, in the form of a shot and a pill. The shot blocks the production of male hormones from the testicles. The pill blocks male hormones that are produced by the adrenal glands which are small glands that sit on top of each kidney. When used together, the amount of male hormones delivered to the prostate gland and thus to the local prostate cancer is greatly diminished. Research shows that many prostate cancer cells will die when male hormones are no longer present. These cells essentially "commit suicide"; the medical term for this is apoptosis. Hormonal treatments are the only form of cancer treatment that kills only cancer cells and no normal cells. Surgery and radiation treatment destroys some normal cells along with the cancer cells. Unfortunately, the hormonal treatments do not eliminate all cancer cells, otherwise this approach alone would be a cure. There is a small percentage of prostate cancer cells that continue to grow whether or not male hormones are present. However for several months and probably for one to one and a half years, the total number of prostate cancer cells decrease from the hormone treatments. This is due to the fact that initially the hormone sensitive prostate cancer cells are killed and eliminated from the body at a faster rate than the hormone insensitive cells are reproducing.
There is a growing number of studies to show a benefit of using hormonal treatment along with external beam radiation therapy versus using external beam alone. There is also evidence that hormonal treatments along with radioactive seed implant is beneficial. Therefore, a commonly used treatment regimen would include 3 or more months of hormonal therapy in the form of shots and pills followed by 5 weeks of external beam radiation, with the radioactive seed implant done at approximately a month after the external beam treatment. The hormonal treatments are continued through the entire radiation treatment, including implant, and up to 3 or 4 months after the implantation (see attached time line). It should be remembered that if hormonal treatment is recommended, this is not a delay in treatment nor is it designed to "hold the cancer in check". It is an active cancer killing form of treatment and there is evidence to support that many patients will have a better long-term outcome when this is used in combination with the external beam and radioactive seeds than if it is not part of the treatment plan. Each case is individual and this will be discussed by the patient's physician.
Short term side-effects for the hormonal treatments (shots and pills) are temporary and may include loss of sex drive, loss of erections in 50-80% of patients (however, approximately 80% who lose function respond to Viagra/Levitra or Cialis), hot flashes, fatigue, and possibly loose stool. The most common short term side-effect from external beam radiation is loose stool which is usually controlled with medication. Occasionally a patient will develop an urinary tract infection (bladder infection) which is treated with antibiotics. The most common short term side-effect from the radioactive seed implant is irritation of urination; for example; getting up more often at night or going more frequently during the day, with possibly a decrease in strength of the urinary stream. This usually clears 2 to 3 months after the radioactive seed implant is completed.
Long-term side-effects are rare. The chance of urinary incontinence (inability to control urination) is less than 1% if the patient has never had a TURP (transurethral resection of the prostate) A TURP is a surgical procedure in which an instrument is put into the penis and the opening in the center of the prostate is enlarged and is commonly known in non-medical terms as the "rotor rooter" procedure. Incontinence is slightly higher if a TURP has been done, however often an implant can still be performed safely on these patients. The chance of severe rectal or bowel complications is less than 2%. The chance of impotence with radioactive seeds as part of the treatment plan is between 15 and 20 %, and is much more favorable than impotence rates reported after the standard radical prostatectomy or nerve sparing prostatectomy. These rates are more favorable in younger patients with no preexisting difficulties.
The chance for cure in early stage prostate cancer is excellent with a greater than 90% cure rate reported in many series. Even in patients with somewhat higher Gleason scores and PSA's the combination of external beam and radioactive seeds has resulted in published results of approximately 75% control rates. It is hopeful that this may be improved with hormonal treatments, and represents the most favorable results in such patients at the present time.