CHICAGO (AP) -- Low-income American women and women in developing countries who are tested for cervical cancer could benefit from faster, more aggressive treatment, two studies suggest.

Some of those women would be treated unnecessarily, but some experts believe the trade-off might save lives in impoverished countries where women often die from a cancer that can be treated if caught early.

"We may have to decide what's feasible, what we can afford and what's the best care for different groups," said University of California, Irvine, researcher Dr. Wendy Brewster, co-author of one of the studies. Both studies appear in Wednesday's Journal of the American Medical Association.

Cervical cancer is preventable and mostly afflicts the world's poorest women. Eighty percent of the 230,000 cervical cancer deaths worldwide each year are in developing countries, according to the International Agency for Research on Cancer. In the United States, black and Hispanic women have the highest death rates for cervical cancer.

Many women in affluent countries get screened annually with a Pap smear, a test in which cells are scraped from the cervix and examined under a microscope in a lab. If the test is abnormal, the patient is called back for a biopsy. If the biopsy shows signs of cancer, the woman and her doctor discuss treatment choices.

In poor countries, however, lab testing and biopsies are rare. In poor U.S. neighborhoods, patients might not get regular Pap tests, or might fail to return for follow-up exams, Brewster said.

The new studies, which explore ways to get more poor women tested and treated, were done in South Africa and in largely Hispanic neighborhoods in Orange County, Calif.

In the California study, 3,521 women were given Pap smears. One group of women stayed at the clinic to await results. If their tests indicated high-grade precancerous lesions, the women had a procedure that day to remove a layer of the cervix. The cervix is the lower part of the uterus that opens into the vagina.

In the comparison group, women with abnormal tests were referred for later follow-up care.

Checking back six months and 12 months later, researchers found that the women in the single-visit group were significantly more likely to have completed their care than women in the comparison group.

Samples for biopsies were taken before treating the women. Those indicted that two out of 14 women had had the procedure unnecessarily because their biopsies were negative. The procedure is considered safe but still carries risks.

In the South Africa study, 6,555 women got two screening tests: one for human papilloma virus, HPV, a common sexually transmitted virus that causes most cervical cancer, and the other a simple, cheap test for precancerous lesions.

The women then were divided into three groups. In the first group, only the women testing positive for HPV were given cryotherapy, a procedure that destroys cells on the cervix by freezing them with nitrous oxide. In the second group, only the women who tested positive for precancerous lesions had cryotherapy.

The third group waited six months for treatment.

The HPV test was more accurate than the cheaper test, but both exams reduced the incidence of precancerous lesions. However, four out of five women in the two groups that got immediate treatment had no precancerous condition.

"Public health interventions inevitably require a trade-off between benefits and risks," said study co-author Dr. Thomas C. Wright Jr., of Columbia University. He said he considered the trade-off reasonable to save lives.

The South Africa study, funded by the Bill and Melinda Gates Foundation, was conducted by researchers at Columbia and at University of Cape Town, South Africa.

"The important thing is to link testing with treatment. If you do that without a diagnostic step, as long as treatment is safe, you're well within the bounds of good medicine," said Dr. Paul Blumenthal of Johns Hopkins University, who co-authored an editorial on the studies in the same issue of the medical journal.

Dr. Rengaswamy Sankaranarayanan, a World Health Organization expert on cancer screening, called the South Africa research "a landmark study, showing a practical way forward to prevent cervical cancer" in countries with fewer resources.

Two drug companies, Merck & Co. and GlaxoSmithKline, are developing promising vaccines to prevent cervical cancer by blocking HPV infection.

"The vaccines are going to be great in reducing cervical cancer 20 years from now," Wright said. But millions of women will die in those two decades of a preventable disease without more widespread screening and treatment.

Copyright 2005 The Associated Press. All rights reserved.