Prostate Cancer: So you’ve been diagnosed with prostate cancer: What now?

David F. Penson, M.D., MPH
Associate Professor
Department of Urology
University of Southern California (USC)

Watch Video (Dan Lin, MD University of Washington Department of Urology)

Men newly diagnosed with prostate cancer face a myriad of choices when considering treatment for their condition. Perhaps the most important thing to remember if you’ve been diagnosed with this disease is that there is no “right” choice of treatment and that each man has to make his own individualized decision regarding therapy for this common cancer.

Although there are a number of reasonable treatment options available to men with prostate cancer, some therapies may be more appropriate than others depending upon how advanced the cancer is at the time of diagnosis. That is to say the cancer is within the prostate gland (localized disease), or has it spread to the lymph nodes or beyond (distant or metastatic disease)? The doctor can usually determine if the cancer has spread beyond the prostate on the basis of a digital rectal exam (DRE), where he or she palpates the prostate with his/her finger, and a blood test known as a prostate-specific antigen (PSA) test. If the health care provider is concerned that the cancer has spread on the basis of the DRE or the PSA test, he or she will often order x-rays, such as a computerized tomography (CT) scan or a nuclear medicine bone scan, to determine if the cancer is metastatic.

While treatment for metastatic prostate cancer is relatively straight forward, treatment choice for men with localized prostate cancer is considerably more involved. There are 5 established therapies for localized prostate cancer: Surgery (radical prostatectomy), radiation therapy (either using external beams or radioactive seed implants), observation, cryotherapy (freezing the prostate) or hormone ablation therapy. To date, no treatment has been shown to be better than another in terms of prolonging survival. Therefore, men must decide on the basis of their personal preferences regarding the side effects of each therapy and their overall health. Hormone ablation therapy will be discussed later in this article, we won’t discuss it further here accept to say it is not curative. Therefore it is not appropriate for men who wish to be “cured” of their cancer (which may be possible with localized disease).

Many patients wonder why they might elect not to have any therapy for their localized prostate cancer, choosing “watchful waiting” and delaying treatment until the cancer spreads or becomes symptomatic, the rationale behind this lies in the old medical axiom “More men die WITH prostate cancer than OF prostate cancer”. To some degree, this statement is true. In 2003, approximately 180,000 men will be diagnosed with prostate cancer but only 35,000 will die of the disease. No doubt some of the discrepancy is due to effective therapy for localized disease (such as surgery or radiotherapy), but at least a portion of this difference is due to the fact that prostate cancer is often a slowgrowing cancer that takes many years to become a problem for men. If a patient is older and has numerous other medical conditions, he may be more likely to die of one of his other problems (such as heart disease or diabetes) than of prostate cancer and there may be no need to treat his prostate cancer.

The doctor can often give a patient some idea of how aggressive the prostate cancer is on the basis of the PSA test and the way the cancer looks under the microscope (known as pathologic differentiation, measured with something called Gleason score). If a patient has a particularly slow growing cancer and other medical conditions, he may choose “watchful waiting”, also known as expectant management. The risk of this approach is that the cancer will spread in the patient’s lifetime and he will lose his chance to be cured. It also carries a certain psychological burden, which may be difficult for some patients. A recent study in the New England Journal of Medicine randomly assigned men to have either surgery or watchful waiting for localized prostate cancer. While there was no difference in overall survival, the men who had surgery were less likely to die of prostate cancer than those who were assigned to observation. This study seems to support the observation that older men with other co-morbid conditions and slower growing cancer can safely be managed with expectant therapy, while younger men in better health may wish to consider more aggressive therapy, such as surgery or radiotherapy for their cancer.

If a patient with localized prostate elects “aggressive therapy”, he can choose between surgery, radiotherapy or cryotherapy. Cryotherapy is an outpatient procedure in which the patient is anesthetized and special probes are placed into the prostate through the skin. These probes are then used to freeze the prostate, hopefully killing the cancer. The procedure is only offered in selected centers and few long-term data are available regarding cure rates. Although it is covered by Medicare insurance, it is still considered somewhat experimental and “unconventional” by many experts.

Unlike cryotherapy, there are long- term data available for both surgery and radiotherapy. While it is not clear which of these therapies is superior in terms of overall survival, it is clear that there are side effects associated with both treatments that must be considered when choosing therapy. The surgery, known as a radical prostatectomy, involves removing the prostate (and sometimes the lymph nodes). The operation usually takes 2-3 hours and can be done through an open incision or with a laparoscopic (surgery with small incisions) approach. Patients usually remain in the hospital about 2 or 3 days after the surgery. During the surgery, a tube (called a catheter) is placed into the bladder through the penis and is usually removed 1 to 2 weeks later. Because the surgery removes the prostate completely, many providers feel it gives a patient the best chance for cure. In addition, follow-up is simple, as cancer recurrence can usually be easily detected with a PSA test. Although the surgery is the most commonly used therapy for localized prostate cancer, it is not without its risks. Obviously, no one likes to have surgery and there are risks associated with any surgical procedure. However, men undergoing radical prostatectomy are at risk for impotence and urinary leakage after surgery. Patients must be aware of these risks when choosing surgery.

Alternatively, patients can elect radiotherapy to treat their localized prostate cancer. This can be given as external beam radiotherapy (EBRT), in which patients undergo external radiation to the prostate 5 days a week, usually for 5 to 7 weeks, or as interstitial brachytherapy, in which patients are anesthetized and radioactive seeds are implanted into the prostate through the skin in a one-time procedure. While radiotherapy may work as well as surgery in terms of survival, few providers think it is superior and many urologists feel it is not as effective as surgery. However, radiotherapy has a number of strengths, including the fact that no surgery is involved and that the risk of impotence and incontinence is less than that of surgery. Unfortunately, as with all prostate cancer treatments, radiotherapy has its disadvantages/side effects as well. These include the risk of bowel irritation and problems with urination. Problems with erections may be similar between nerve sparing radical prostatectomy and seeds. In addition, follow-up is somewhat more complicated after radiotherapy, as the PSA test may vary due to benign regrowth of the prostate and, therefore, is not an unequivocal marker of cancer recurrence (like it is after surgery). There are currently a number of ongoing studies comparing surgery and radiotherapy to determine which is better for most patients with prostate cancer. Unfortunately, it will be a number of years until we get results from these studies. Until then, patients will have to weigh the risks and benefits of all therapies for prostate cancer and choose the one that fits them best. Doctors can provide men with useful information that may help with this difficult decision, but, ultimately, the choice lies with the patient himself, as he is the only one who can decide which therapy is “best” for him.

In the case of metastatic prostate cancer, the decision regarding therapy is somewhat easier. The cornerstone of treatment for metastatic prostate cancer is “hormone ablation therapy”. The rationale for this treatment lies in the fact that prostate cancer is a “men’s cancer” and often requires the male chemical or hormone testosterone for tumor growth. If the testosterone is removed from the body, then the tumor will often go into “remission”. As 95% of a man’s testosterone is made in the testicles, the best way to remove the testosterone is to stop the testicles from producing the chemical. This can be accomplished one of two ways: either surgical removal of the testicles (a relatively minor surgical procedure known as an orchiectomy) or administration of injectable medications (known as LHRH agonists, such as Lupron, Zoladex, Eligard, and Viador) which signal the testicles to stop producing testosterone. Some physicians will also have the patients take pills (known as androgen blockers, such as Eulexin or Casodex) which further block the effects of testosterone. Medical and surgical hormone ablation therapies are equally effective in reducing testosterone levels and putting the cancer into remission. The key difference is that the surgical therapy is permanent, while the medical therapy is temporary and requires additional shots anywhere from once a month to once a year. Regardless of whether a man chooses medical or surgical hormone ablation therapy, there is a risk of side effects from the treatment. These include: decreased libido, difficulties with erections, stomach upset, fatigue and hot flashes. For this reason, many men elect medical hormone ablation, as they can be treated intermittently, alleviating these side effects. In fact, some patients who have metastatic prostate cancer and no symptoms will choose to observe the cancer and only start the hormone ablation therapy when symptoms develop. Again, this is a personal decision that every man must make for himself. It is important to note that while the hormone ablation therapy is quite effective in controlling the cancer, it does not cure the cancer.

Over time, many prostate cancers develop resistance to this type of therapy and start to grow again. Although this often takes many years, when the cancer becomes “hormone-resistant”, it is a poor prognostic sign and there are few established treatments available for these patients. There are currently numerous experimental therapies available for men with this form of advanced prostate cancer. Hopefully, these studies will result in the discovery of new treatments for metastatic prostate cancer in the future.

For additional information on this release, please contact:

Debi Johnson

Phone: (425) 971-5822

Email:

Source: David F. Penson, M.D., MPH

Website: N/A

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