A new test called the ThinPrep Pap Test is gradually replacing conventional Pap smears in medical centers nationwide and is currently available in most major cities. Clinical trials indicate that the ThinPrep Pap Test is 65% more effective than the conventional Pap smear in detecting cervical cancer and precancerous lesions.
Cervical cancer accounts for 6% of all cancers in women, with an estimated 16,000 new cases and 5,000 deaths in the United States each year. Cervical cancer is one of the more preventable types of cancer, especially when detected early. The extent of disease at the time of diagnosis is a crucial factor in determining the prognosis. Widespread use of a screening test called the Pap smear has led to a decline in the number of deaths resulting from cervical cancer; however this test is more than 50 years old and is associated with a high false-negative rate, which means that the test often fails to identify precancerous or cancerous conditions.
The high false-negative rate with conventional Pap smears may be the result of sampling errors. With the conventional method, physicians use a collection device to scrape the cervix and then smear a portion of the cervical sample onto a slide. As a result, the specimen can contain blood and mucus, which cloud visibility of the cells. In addition, the collection device is then discarded, along with about 80% of the specimen.
The ThinPrep Pap Test improves upon the conventional method by improving the way the sample is prepared. With the ThinPrep Pap Test, the physician uses the same procedure to collect a sample from the patient, but then rinses the collection device into a vial of preserving solution, thereby capturing the entire sample. The vial is then sent to the laboratory, where an instrument called the ThinPrep 2000 processor disperses and filters the contents to reduce blood, mucus and inflammation. This instrument then deposits a thin, even layer of cervical cells onto a slide. This slide contains a more uniform sample of well-preserved cells than that offered by the traditional smear method.
In clinical trials, the ThinPrep Pap Test reduced the number of inadequate samples by more than 50%. In addition, results from the clinical trials indicate that the test is 65% more effective in detecting cancerous and precancerous lesions.
The ThinPrep Pap Test received FDA approval in the spring of 2000 and is becoming increasingly available at medical centers nationwide. The test will initially cost a few more dollars than the conventional method, but researchers predict that it will eventually save the healthcare system hundreds of thousands of dollars by detecting cervical cancer earlier, when it is most treatable. In addition, the improved quality of samples will reduce the number of unnecessary repeat tests.
Cervical cancer is very preventable. It is crucial that women receive an annual screening exam in order to detect cervical cancer early when it is most treatable. Women over the age of 18 are advised to receive an annual Pap test. The ThinPrep Pap Test is a promising alternative that may offer more accurate results than previous tests. Women interested in receiving this test may wish to consult with their physicians to determine whether the test is available in their area.