Half a century ago, a safe, inexpensive screening test was developed that could have put a virtual end to the leading cancer killer of women.
The problem is, many women didn't get the test--and many still don't.
The Papanicolaou smear--better known as the Pap test--was a breakthrough in fighting cervical cancer, then the top cause of cancer deaths among American women and still the top cancer killer worldwide.
The test detects cancerous cervical cells and abnormal cells that, left untreated, often become cancerous. Early detection with the Pap test has sharply reduced the threat of cervical cancer.
National records show incidence and mortality rates have fallen 40 percent in the last two decades. Records going back to 1950 for white women show incidence and mortality rates have fallen 75 percent since then.
Nonetheless, this year, about 15,000 women will be diagnosed with cervical cancer, and about 5,000 will die of the disease. Those numbers should be far lower, authorities say.
"We shouldn't have cervical cancer in our country," said Michael Steller, a gynecological oncologist at the National Cancer Institute. "It's preventable if you get a routine Pap smear."
A Pap smear is a slide of cells gently scraped from the neck of a woman's uterus, or cervix. Its developer, the late George Papanicolaou, a Cornell University Medical College researcher in cell biology, capitalized on the fact that cervical cancer is one of the few cancers with well-defined precancerous stages.
After the test was introduced in 1945, it caught on slowly, recalled John Mikuta, 71, a professor of gynecological oncology at the University of Pennsylvania Medical Center.
Taking cells from a woman was easy, but analyzing them under a microscope was like looking for a needle in a haystack. In a smear of 300,000 cells, as few as 10 or 20 might be abnormal.
"Originally, it was a very laborious process," Mikuta said. "It took a pathologist 30 to 40 minutes to read a slide." Now trained technicians can do it in five or six minutes.
Indeed, to deter commercial laboratories from sacrificing accuracy to quantity, federal regulators in 1988 imposed limits on technicians' daily slide quotas and other quality-assurance measures. A reputable lab will miss about 5 percent of abnormal smears, said Michael Henry, a pathologist and lab director at the National Naval Medical Center in Bethesda, Md. The safeguard is that abnormal cells usually take up to a decade to develop into invasive cancer.
Yet tragic mistakes have been made. Last month, a Wisconsin lab was fined for misreading the Pap tests of two women who later died.
"There's a greater awareness of the issue, and women are asking, `Why was this missed?' " Henry said. "I think that's good because it makes the labs try to do better."
If a smear is abnormal, diagnosis normally involves a colposcopy--inspection of the cervix under magnified illumination--and possibly a biopsy. Mildly abnormal cells may revert to normal without treatment.
More severe abnormalities or early stage cancer that has not spread usually can be completely cured by destroying the tissue with lasers, electrical treatment, cryosurgery (which uses cold) or other methods. If the cancer has spread, a hysterectomy or radiation therapy may be recommended. If cancer has not spread very far, about 80 to 90 percent survive. About 60 percent survive late-stage, invasive cancer involving the lymph nodes.
Alan Lichter, a University of Michigan radiation oncologist, said: "Tremendous progress has been made, but this is almost completely a preventable cause of death. Cure rates approach 100 percent if it's detected before it becomes invasive."
A study last fall by the UCLA Center for Health Policy Research found screening rates correlate with socioeconomic and cultural disadvantages and age. Large percentages of low-income women, the uninsured, high school dropouts and the elderly had not been screened in the year before the survey. Asian women were the least likely to have been screened.
Medicare began covering Pap smears four years ago, and free Pap tests are available at many public health clinics, though obtaining treatment after diagnosis is often a problem.
"Also, there's a belief among women that if you don't have symptoms, nothing's wrong," said gynecological oncologist Patricia Braly, of the Louisiana State University School of Medicine.
Dr. Edward L. Trimble, of the National Cancer Institute, said that many women over 60 presume they are no longer at risk of cervical cancer, and some doctors share this misunderstanding: "We have to find a way to get the message out to them."
Meanwhile, the American College of Obstetricians-Gynecologists recommends that most women get a Pap test every year.