Two large studies suggest new ways to detect people in good health for cervical cancer or prostate, but a third disappointed those who hope for a way to detect early signs of deadly tumors of the ovary.
The researchers found:
_For women 30 and more, a test for the virus, HPV, is preferable to a PAP test to predict the risk of cervical cancer, and those who test negative on both can safely wait three years to be checked again.
This unique PSA blood test at age 44 to 50 could help predict the risk of a man of advanced cancer of the prostate or dying of it until 30 years later. The PSA test is known to be reliable, but this way he separates men who need close supervision of those who are so low-risk they can ignore testing for five years or more.
_Screening women with no symptoms of cancer of the ovary with a blood test and ultrasound examination is harmful. It did not prevent the death and led to thousands of false alarms, unnecessary surgeries and severe complications.
The latest study is a warning to people who get the tests that are not recommended or that if screening may be ill ever screening.
"The answer is that this could not many, said Mr. Allen Lichter, Director Executive of the American Society of Clinical Oncology." The Group publishes these and 4,000 other studies Wednesday, before its annual meeting, next month.
Cervical cancer is easy to prevent. It is very slow growth and testing research on precancerous cells and allows early treatment. The new study was the first great review most recent screening tool, HPV testing, with or without PAP in current practice.
For a test of PAP, scraped from the cervix, uterine gateway, cells are checked under a microscope. But it may lack problems or raise false alerts.
HPV tests to detect the human papilloma virus, which causes most cases of cervical cancer. But HPV is "cold" regions nil - most of the young sexually active have been exposed to it, said Debbie Saslow, Director of the American Cancer Society for cancer of the breast and gynecological. Most infections go away on their own. they have only a risk of cancer when they last a year or more.
Younger women tend to have infections in the short term, so the Pap test is a better way of their screen. HPV tests are approved option with Paps for women 30 and older, and the cancer society says that if a woman tests negative on both, it can wait three years to be thrown again. Few take this advice, though.
"Their annual Pap and doctors still want to give them want even of women" and is rationing of care test less often, think said Saslow.
The new study gives "very, very strong support" for testing, said Lichter.
Hormuzd Katki of the National Cancer Institute investigated more than 330 000 women cross HPV and Pap tests Kaiser Permanente Northern California for five years.
Year only about three of 100 000 women each developed cancer of the cervix after negative HPV and Pap tests. HPV tests were two times more as good as Paps to predict risk. Adding a Pap after a negative HPV test has little done to improve the prediction of the risk.
However, if an HPV test was positive, a Pap test to confirm or the need for follow-up.
The study did not look at the downside of HPV testing - how many false alarms and unnecessary procedures it triggered. Tests for HPV costs between $80 and $100 compared to $ 20 to $ 40 for Paps.
The study of prostate sought a better way to use the PSA tests, which are troublesome because PSA can be high for many reasons beyond cancer, and doctors don't know that cancers need treatment or whether if screening saves lives. Most groups do recommend APS, but most men over 50 years to do anyway.
The new study "will not put an end to the controversy, but it suggests a very interesting way," Lichter said.
Researchers at Memorial Sloan - Kettering Cancer Center in New York has used blood samples stored 12 000 Swedish men gave for a study of heart for decades, when most were 44 to 50 years. They were also second samples from some of them, six years later and samples of other men in 60 years.
Research 27 years later, scientists have seen that 44% of cancer deaths occurred among men whose initial PSA had been in the top 10 per cent, whereas they were 44 to 50 years.
Conversely, entering below the median means very little risk of cancer years later.
"They're identifying a group of guys who have need to be screened, or must be screened less often,", said Dr. Otis Brawley, Chief Medical Officer of the cancer society.
The results are "provocation", but this type of study cannot prove that screening prevents deaths, said Dr. Matthew r. Smith, Massachusetts General Hospital Cancer Center. Few Swedish men have been treated for prostate cancer, like most men are today, which may affect survival.
The National Cancer Institute, the Swedish society of Cancer and several foundations paid for the work, and a researcher holder of patents for two PSA tests.
Baseline PSA in men in their forties can be recommended even, said Brawley. Cancer society says men should be informed of the risks and benefits of PSA testing starting at age 50 and earlier for blacks and persons with a family history of prostate cancer.
Cancer of the ovary Government-funded study involved nearly 80,000 women. Half was selected every year with a four-year ultrasound and a blood test for six years. The blood test sought to CA-125, une substance often high in ovarian cancer.
After 13 years, there was no major differences in cancers found ovarian or death resulting from the disease. Screening found only 212 cancers while giving the 3,285 false alarms that led to 1,080 unnecessary biopsy surgeries and severe complications 163.
"Many people said ' how the screening be harmful? This thing the documents, "said Brawley.
The results do not apply to the use of these tests on women who have symptoms of cancer of the ovary or abnormal physical examinations. It is still the best way to check for cancer of the ovary in these cases.
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Online:
CDC on HPV testing: http://www.cdc.gov/hpv/Screening.html
On the HPV cancer society: http://tinyurl.com/44gnadx
Scientific journal of cervical cancer: http://tinyurl.com/6lc2rzg
Oncology Society: www.cancer.net
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