RISING PSA AFTER SEEDING/RADIATION

(External radiation or implant or combination therapy)

PSA stands for Prostate Specific Antigen and is a blood test that is used to screen for the presence of prostate cancer and, in those men known to have prostate cancer, PSA becomes a tool to measure the effectiveness of the treatments that have been used.

WHAT IS PSA, AND HOW DO WE MEASURE IT?
An antigen is a medical or biological term for a substance or protein that stimulates the body to make antibodies.

Prostate Specific Antigen is a protein found in the serum that is unique or specific for the prostate, both normal prostate and prostate cancer cells. In the case of prostate cancer, the PSA will reflect the presence of the tumor, wherever the cancer cells are present in the body. No other tissues or body parts can make Prostate Specific Antigen. Therefore, the PSA levels can be measured in an individual's serum and with this information we are able to follow prostate cancer. PSA, itself, is not harmful and a rising PSA in the blood by itself is only a laboratory test or assay of a small amount of this unique protein in your blood. It is the prostate cancer which must be treated, not the PSA.

Almost all prostate cancer cells manufacture PSA and as the prostate cancer grows, more PSA is released into the blood stream and the PSA values rise. Conversely, if the cancer is diminishing the PSA values fall. This fact allows us to track treatment effectiveness using PSA levels.

WHAT IS THE SIGNIFICANCE OF THE PSA IF I HAVE PROSTATE CANCER?
When a man has had a radiation therapy for localized prostate cancer, the entire prostate is treated and hopefully all of the cancer cells will have been killed or at least made unable to grow further. The PSA level, which is a reflection of the size of the cancer, should fall as the cancer cells die. Because not all cells are killed immediately and many of the non-cancerous prostate cells will not be killed, some cells will remain that do manufacture PSA. The normal values printed on laboratory sheets that say ‘less than 4.0’ are screening values for men who still have their prostate. After radiation, we would hope that the PSA will fall to very low levels, certainly less than 1.0. But whatever the lowest value achieved, we look for a stable value. If the PSA falls and then starts to rise, this almost always means that cancer cells are growing once again.

Said again, if a man has a rising PSA after radiation therapy for prostate cancer, he has residual or recurrent prostate cancer. The PSA rise does not tell where the cancer is, only that it is somewhere. Prostate cancer may return in the prostate (local recurrence) or it may return in any body tissue away from the prostate (distant spread), most commonly in bone or lymph nodes. In most cases the rate of rise of the PSA reflects the growth rate of the residual cancer.

WHEN SHOULD THE FIRST PSA LEVEL BE DRAWN AFTER RADIATION THERAPY?
While there is no set standard, we measure the PSA values every three months for the first year, every six months the second year, and then yearly for ten years.    

WHAT TYPE OF PSA TESTS DO I NEED?
Free PSA, Complex PSA (PSA-ACT), hK2 and other new PSA screening tests have no benefit over the current used PSA tests in patients who already have a diagnosis of prostate cancer. They are helpful only in screeing situations in helping us determine who needs or does not need a biopsy.

BENIGN PSA 'BOUNCE' AFTER IMPLANTATION
Between 8 months and 2 years after seed implantation a slight rise or 'bounce' of PSA measurement may occur in 3 out of every 10 patients. This BENIGN rise is not easy to explain and may result from some form of prostate inflammation as the radiation dose begins to diminish. In these cases the PSA will usually fall again at the next interval. During this period, we have no way of being certain whether a single rise is due to recurrence of cancer or whether it is the benign bounce just described. We need to repeat the PSA at regular intervals, such as every three months, during this period. If the PSA rises three consecutive times, a recurrence of the cancer is strongly suggested.

WHAT TO DO WHEN THE PSA LEVEL IS FOUND TO BE RISING?
Whenever cancer recurrence is suspected, we try to determine the whereabouts or stage of the cancer. That is, where is it and how much is there? If we can localize the cancer, we have a better chance of treating it and following its course. Statistically, the most common place for return of the cancer is in the prostate itself.

The tests that will be done might include a rectal examination and ultrasound and biopsy of the prostate to look for local recurrence. Other prostate cancers will recur at distant sites, particularly bone, and more particularly, the bones of the pelvis and spine, or the lymph nodes of the pelvis. To complete the evaluation, a bone scan, chest X-ray, CAT scan or MRI scan might be done depending on how recently those tests might have been done.

WHAT TO DO?? - THE THREE SCENARIOS

CANCER IS FOUND IN THE PROSTATE AND NOWHERE ELSE?

First, IN ALMOST ALL CIRCUMSTANCES, NO MORE RADIATION MAY BE GIVEN TO THE PROSTATE!!. The tissues around the prostate would not tolerate further treatment and severe rectal and bladder problems would be expected.  The rare and possible exception would be someone who received an implant that missed a portion of the prostate and this was the ONLY area of recurrence of the cancer.

If the cancer is found in the prostate suggesting an incomplete response to radiation and if no other evidence of cancer is found, the cancer might still be curable by removing the prostate. Radical prostatectomy after radiation is feasible, but considerably more difficult because of the radiation effects on the tissues surrounding the prostate. Factors that must be considered before proceeding to surgery are the chances incontinence (10-15%), impotence ( almost 100%), rectal injury requiring temporary colostomy (5%), stricture or scar formation at the bladder-urethra connection (10-15%), and the possibility that the bladder neck will have significant radiation damage so that total removal of the bladder is necessary. Bladder removal would entail diversion of the urine flow to a stoma (bag on the skin) or some other type of urinary diversion.

Hormone therapy could be started immediately, or delayed until symptoms of cancer growth are present. There is no solid proof that treating early with hormones extends life expectancy, but some evidence exists that treating early will prevent symptoms for a longer period of time. If the side effects of hormone deprivation are unacceptable (impotency, no libido, hot flashes), then delay in treatment may improve quality of life without shortening life expectancy.

Alternatively, the cancer could be left alone. If the PSA rise is slow, suggesting slow growth, particularly in men with advanced age or other medical problems, watchful waiting may be the wiser of choices.

CANCER IS FOUND AT DISTANT SITES OR BOTH DISTANT AND NEARBY?
If the cancer is found elsewhere, even at only one spot, it is very likely that more areas exist that cannot be seen. Surgery in these situations is no cure. Sometimes a specific area will cause symptoms, or in the case of a bone, have the risk of fracture. In these circumstances, we recommend radiation to the specific area. If a weight-bearing bone is not involved and no symptoms are present, the best options are the use of hormone treatments or observation until symptoms or danger are imminent.

There is no solid proof that treating early with hormones extends life expectancy, but some evidence exists that treating early will prevent recurrence for a longer period of time. If the side effects of hormone deprivation are unacceptable (impotency, no libido, hot flashes), then delay in treatment may improve quality of life without shortening life expectancy.

Another approach may be the rate of rise of the PSA. Experience suggests that the faster rising PSAs will cause trouble sooner. A recent study suggested that if the PSA doubles within a year that a high probability for bone spread exists. If the ‘doubling time of PSA’ is more than one year, many patients remained without cancer problems for 6 or 7 years. Another approach would be to look at the grade of the original cancer. Higher grades (8,9,10) would be more likely to spread earlier and more aggressively and therefore might benefit from early treatment with hormones.

THE AREA OF RECURRENCE CANNOT BE FOUND?
This is a dilemma.  We could not recommend removal of the prostate without evidence that the cancer is actually there. Repeated biopsies would be suggested until we are sure that the cancer is not in the prostate.

As mentioned above, hormone treatment for PSA elevation without other findings is controversial. There is some proof that treating early with hormones extends life expectancy, and much evidence exists that treating early will prevent recurrence for a longer period of time. If the side effects of hormone deprivation are unacceptable (impotency, no libido, hot flashes), then delay in treatment may improve quality of life without shortening life expectancy too much. As mentioned above, the PSA rate of rise (or the time it takes the PSA to double in value) and the grade of the cancer should be taken into consideration when making a decision whether or not to start treatment.

SUMMARY
Some the these issues have not been completely described here, including the various forms and side effects of hormone deprivation therapy. Your urologist or radiation oncologist will be happy to go over this with you in more detail or provide further reading.