Results of four large, new studies on the benefits of screening for reproductive cancers in men and women raise more questions than they answer.

Two prostate cancer studies failed to show that widespread screening for the disease saved a significant number of lives. One study, done in Europe, where prostate-specific antigen (PSA) testing isn't common practice, followed 162,000 men. It showed a small reduction in deaths, about seven fewer deaths per 10,000 men screened. In the United States, where PSA testing is recommended in men over 50, researchers found it didn't save lives among the 76,000 men studied. Both studies suggested that when screening resulted in a positive diagnosis, it led to needless, uncomfortable treatments in large numbers of patients.

"These studies suggest that treatment risks and benefits need to be part of the equation," said William P. Hogle, RN, clinical manager of the University of Pittsburgh Cancer Center, on the question of how to advise men who are considering undergoing PSA screening, particularly men over age 70. "I believe patients should be informed prior to screening. This approach is a slight paradigm shift from that of test first, consider treatment options second."

Two ovarian cancer studies. Preliminary results of a study in the United Kingdom of 200,000 postmenopausal women showed that 90% of ovarian cancers could be detected early if a positive CA-125 blood test was followed by transvaginal ultrasonography. Previously, the rate of false positives made the blood test unreliable.

In stark contrast, another study of 34,261 women conducted by researchers at the University of Alabama at Birmingham Comprehensive Cancer Center concluded that the combination of blood test and transvaginal ultrasonography didn't detect early-stage ovarian cancer and led to unnecessary surgery. Together, the screening methods detected 70% of ovarian cancers-but only in their late stages.

"We're still not recommending screening except in high-risk women," said Paula Anastasia, a clinical nurse specialist at Cedars-Sinai Medical Center in Los Angeles. "That's the bottom line." The British study offers a ray of hope for early detection, but it won't be completed for five more years, she said, and it's too early to advise patients without symptoms or who aren't at high risk to be tested.

Annemarie Mannion

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