Study's Finding Could Lead to More Biopsies
And, Some Worry, Unnecessary Treatment
By DAVID ARMSTRONG
Staff Reporter of THE WALL STREET JOURNAL

The standard blood test used to screen for prostate cancer is highly inaccurate, failing to flag eight of every 10 men under 60 who are later diagnosed with the disease, according to a new study. The finding promises to amplify debate over medical practices concerning the common male malignancy.

The study, in this week's New England Journal of Medicine, said the results of the blood test could be dramatically improved by simply lowering the threshold for what is considered a problematic result.

But lowering the threshold would likely lead to far more prostate biopsies -- operations in which small pieces of the prostate are extracted to determine definitively whether cancer is present. And that in turn, could mean more men undergo an invasive medical procedure unnecessarily, because they don't actually have cancer. Indeed, just 30% of biopsies performed wind up detecting prostate cancer.

About three-quarters of the men over 50 in the U.S. have been screened by the test, known as the prostate-specific antigen test, or PSA. The new recommendations could mean many more men would face a tough decision about detection and treatment.

The recommendations are the latest salvo in the long-running debate over whether the prostate-cancer screening does more harm than good. The American Cancer Society recommends doctors offer yearly PSA tests and digital exams to male patients over age 50 with at least a 10-year life expectancy. But other medical groups say that while screening could be helpful in detecting early-stage prostate cancer, the evidence is mixed that early detection improves the disease outcome.

Indeed, some doctors say men can often live for years with prostate cancer before intervention is required, and early detection simply means some men must live longer with anxiety over having cancer, or undergo unnecessary treatment. That may involve surgery or radiation, which can lead to side effects including incontinence and impotence. Even the biopsies themselves, while not as painful today as in the past, can still be uncomfortable and carry a small risk of infection or bleeding.

Prostate cancer is an extremely common and deadly form of cancer, second only to lung cancer as a cause of cancer-related deaths in men. The American Cancer society predicts that 220,900 men will be diagnosed this year in the U.S., and 28,900 will die.

Currently, the standard for the PSA test, which measures how many billionths of a gram of prostate-specific antigen are present in a milliliter of blood, is that anything above four billionths of a gram indicates the likelihood of cancer. Those patients are then advised to have a biopsy. The new study recommends lowering that threshold to 2.6 from four.

The authors -- from research centers in Boston, Chicago and St. Louis -- report that the current standard misses 82% of the cancers in men under 60 and two-thirds of the cases in men over 60.

Lead author Rinaa Punglia, a radiation oncologist at Brigham and Women's Hospital in Boston, said the researchers' results determined that lowering the threshold for recommending a biopsy to 2.6 can double the cancer detection rate in men under 60 to 36% from 18%. For older men, the rate increases to 60% from 35%.

More Biopsies

Howard Parnes, chief of the prostate and urologic research group at the National Cancer Institute, praised the work of the researchers, but said lowering the PSA standard has risks, including subjecting more men to biopsies that are likely to be negative. In the study, which examined cases involving 6,691 men enrolled in a prior study done at the Washington University College of Medicine, about 7% of the men fell in the PSA range of 2.6 to 4 and would thus be advised to have a biopsy under the new recommendation.

In addition, Dr. Parnes said many men may have a type of prostate cancer that does not pose a serious health risk. "Some of the disease you pick up doesn't need to be found," he says.

As evidence of the controversy surrounding PSA testing, the journal also published a companion editorial that rebuffs the suggestion of the study authors that the PSA standard be lowered. The editorial authors, from the Erasmus Medical Center in Rotterdam, the Netherlands, warned that lowering the PSA threshold for performing a biopsy will increase the rate of overdiagnosis and, potentially, overtreatment.

The editorial authors said any decision to lower the PSA threshold should come from clinical trials designed to show whether men who undergo screening are less likely to die of prostate cancer than those who don't. Two such trials are under way -- one in the U.S. and another in Europe -- but results are not expected for several years.

With so much debate surrounding the need for early detection, in the end experts say the screening decision comes down to a personal choice by the patient himself.

The Need to Know

Some men may be happy not knowing if they have the disease, particularly if there is no evidence early detection will reduce their risk of death. However, others may prefer to know so they can at least monitor their condition to make sure it is not worsening.

For men considering whether to undergo screening, the cancer prevention and control division of the Centers for Disease Control and Prevention has recently published a prostate-cancer screening decision guide. The site lays out the pros and cons, and says that ultimately, "the decision is yours." It is available at the agency's Web site.

Write to David Armstrong at david.armstrong@wsj.com.

Updated July 24, 2003 12:31 a.m.

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