Prostate cancer is the second most common cancer affecting American men, after skin cancers. The American Cancer Society estimates that more than 232,000 new cases of prostate cancer will be diagnosed in 2005, and that one in six men will be diagnosed with it during his lifetime. The good news is that when prostate cancer is diagnosed early the five-year survival rate is near 100%.

Doctors often recommend radical prostatectomy , radiation therapy, or watchful waiting for prostate cancer that has not spread beyond the prostate. Radical prostatectomy is the surgical removal of the prostate gland and nearby tissues; radiation therapy destroys the ability of cancer cells to grow and divide. Patients who choose watchful waiting are not treated right away, but are carefully monitored through regular prostate exams, ultrasounds, and measurements of blood prostate-specific antigen (PSA) levels .

In a 2002 article in the New England Journal of Medicine , researchers reported that in patients with early prostate cancer, radical prostatectomy compared favorably to watchful waiting after six years of follow-up. But early-stage prostate cancer tends to grow slowly, which makes six years a relatively short follow-up period.

An estimated 60,000 men in the United States undergo radical prostatectomy each year even though it is unclear whether its considerable risks—including persistent impotence and urinary incontinence—outweigh its benefits of longer survival.

Now, in the May 12, 2005 New England Journal of Medicine , the researchers present new results from that study, after nearly 10 years of follow-up. They report that compared to watchful waiting, radical prostatectomy significantly reduces the risk of the cancer spreading beyond the prostate gland, the risk of death due to prostate cancer, and the risk of death from any cause.

About the Study

Between 1989 and 1999, the researchers recruited 695 men younger than age 75, with newly diagnosed, untreated prostate cancer that had not spread beyond the prostate. The men were randomly assigned to either undergo radical prostatectomy or watchful waiting.

Every six months for the first two years of the study, and then every year after that, the men had a clinical exam and blood tests (including a PSA test).

During a follow-up period of about 10 years, the researchers noted how many men in the radical prostatectomy and watchful waiting groups had their cancer spread beyond the prostate, died from prostate cancer, or died from any cause.

The Findings

Ten years after diagnosis, patients who had had a radical prostatectomy were 44% less likely to die of prostate cancer than patients who had been assigned to watchful waiting. This was a significant difference in favor of the surgery group.

The risk of cancer spreading locally to the area beyond the prostate was significantly greater for the watchful waiting group at five years. This risk increased over time, with patients in the radical prostatectomy group being 67% less likely to encounter local progression by ten years after diagnosis.

During the first five years of follow-up, the incidence of metastasis, or the spread of cancer to other parts of the body, was similar for the surgery and watchful waiting groups. But at ten years, patients in the radical prostatectomy group were 40% less likely to have had their cancer spread to another part of the body than the watchful waiting group. Again, this was a significant difference.

For the first five years of follow-up, the risk of death from any cause was similar for the two groups. But at ten years, members of the surgery group were 26% less likely than members of the watchful waiting group to die from any cause.

How Does This Affect You?

Prostate cancer tends to progress slowly so it is important to compare how treatments stack up against one another in the long-term. This study demonstrated that advantages of radical prostatectomy became more pronounced over time, compared to watchful waiting.

Though this seems to strike a blow for the watchful waiting strategy, there are some things to consider. First, the study did not take into account the serious adverse effects associated with radical prostatectomy. Second, it also did not consider radiation therapy, one of the main treatments used for localized prostate cancer. Finally, more than 75% of the men entered this study with stage T2 tumors, which are large enough to be felt by a physician during a digital rectal exam. Only 12% had stage T1c tumors, which are too small to be felt, but are identified because of an elevated PSA level.

PSA testing has was introduced as a screening tool for prostate cancer in the late 1980’s and has become increasing popular among American men over the past 10 years. As a result, prostate cancers are likely to be identified at an earlier stage than they were during the course of this study. And while radical prostatectomy may have had greater long-term benefits than watchful waiting for a stage T2 cancer, the same might not be true for a prostate cancer diagnosed at an earlier stage. In fact, in older men (> 65) whose prostate cancer is identified only after PSA testing, there is no reason to believe that radical prostatectomy is better than watchful waiting.

If you are diagnosed with prostate cancer, talk with your doctor about the best course of action. Your physician should consider many factors, including your age, family history, overall health, the stage of your cancer, and your treatment goals before making his or her recommendation.