Now, in the largest and longest study of its kind, urologists at Johns Hopkins have developed a simple method for assessing the risk these men have for developing deadly metastatic cancer.

"The first thing patients want to know after their PSA rises following surgery is how long they have to live," says Patrick Walsh, M.D., Hopkins' chief of urology, who removed the prostates of the 2000 patients in the study. "And the first thing doctors want to know is what type of follow-up treatment the patient needs. Up until now, there hasn't been any sure way to know."

In the most extensive follow-up study on the natural course of prostate cancer after surgery, Walsh and his colleagues compiled 10,000 patient-years of data from 1982 to 1997. The men were followed for an average of 5.3 years. From this information, they developed a chart physicians and patients can use to pinpoint the risk for developing metastatic cancer, which typically invades the bones of men with prostate cancer.

"Doctors used to say, 'You've recurred, but we aren't sure what that means,'" says Alan Partin, Ph.D., a co-author on the study, which appears in today's Journal of the American Medical Association (JAMA). "Now they can say, 'You've recurred, and we know your risk for developing advanced cancer.'"

The chart places men into different risk groups using three common measures: the so-called Gleason score from the removed prostate (a measure of the cancer's severity and aggressiveness); timing of the rise in PSA level (either before or after two years post-surgery); and the length of time it took the PSA level to double (either greater or less than 10 months).

A man in the lowest risk group (with a moderately severe tumor, PSA recurrence after two years post-surgery, and PSA doubling time greater than 10 months) has a 95 percent chance of being metastasis-free three years after the PSA recurrence; an 86 percent chance at five years; and an 82 percent chance at seven years.

"When men see their PSA levels rise again, they think that means the cancer is back and they need to get treated aggressively right away. But that isn't always the case," says Mario Eisenberger, M.D., a Hopkins oncologist and study co-author. "Patients may live for years without having the cancer spread. This information will better equip doctors and their patients to decide who is a candidate for additional therapy."

The study is critical for future drug research as well, says Partin, because it provides essential baseline data.

"Before, it was difficult to know if a drug was helping, because you couldn't be sure what the disease would have done on its own," he says. "Now, researchers can compare their treatment groups with our study group and tell if their treatment is improving survival."

Other findings from the study:

* Men who experienced rising PSA levels (304 out of 1,997) remained free from metastatic cancer an average of eight years.

* After developing metastatic cancer, as confirmed by imaging techniques such as bone scans, the average time to death was five years. However, men who developed metastases eight or more years following surgery had a much better outlook.

* At 15 years post-surgery, a projected 82 percent of men will still be free from metastatic cancer and considered cured.

In an accompanying editorial, Howard I. Scher, M.D., of Memorial Sloan-Kettering Cancer Center in New York, writes:

"The initial importance of this study is that it provides evidence that a rising PSA level after surgery is not a death warrant for all patients. Patients and physicians must place these results in context, recognizing that left untreated, the natural history of prostate cancer is to progress.

"... The objectives of treating a rising PSA level are to prevent metastases, symptoms, or death due to prostate cancer. Central to this approach is the ability to define and to redefine continually the prognosis of patients as the natural and treated course of their disease unfolds.

"Not all patients with relapsing disease have an equal risk of death from prostate cancer and only some will develop clinical metastatic disease or symptoms of disease in their lifetimes. Do all need immediate intervention? No. Do all need any treatment? No."

Dr. Scher adds: "For the patient with a rising PSA value, case management requires the continued assessment and reassessment of the competing risks of metastatic progression relative to the efficacy and morbidity of proposed treatment. All factors -- clinical, pathologic and molecular -­ should be evaluated as potential predictors of outcome. These considerations transcend traditional stage groupings.

"By limiting interventions to patients with similar prognoses, physicians will be in a position to frame treatment recommendations in the context of the patient who asks, ‘Why do I need this treatment? And what will it do to or for me, for how long, and at what cost?'"

Related websites:

Hopkins' Brady Urological Institute

Graphic of radical prostatectomy

Walsh's home page

Partin's home page

[Contact: Brian Vastag ]

05-May-1999

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