Whatever happened to the annual pap smear?

The reading programs at Rhode Island College, Providence College and Roger Williams University selected the book, The Immortal Life of Henrietta Lacks by Rebecca Skloot, as required summer reading for incoming freshman last year. This book is a nonfiction biography of a poor, black, working mother of five children who died of cervical cancer at the age of 31. The work is a masterpiece of investigative reporting because it reads like fiction, weaving together the life of a patient whose cancer cells became known as “HeLa” cells and the scientific history of how these cells helped scientists unravel the mystery of DNA, find a cure for polio, and produce medications for leukemia, influenza, and many other diseases. In 1951, when Lacks was diagnosed with inoperable cervical cancer, screening for cervical cancer was in its infancy. George Papanicolau had first reported that cervical cancer could be detected by means of a vaginal smear in 1928, but his work was not recognized until 1943, when he and Herbert Traut reported that smears could be used to diagnose cervical cancer at an early stage. At the beginning even pathologists were generally opposed to the Pap smear because it was an extremely complicated, time-consuming test with uncertain results. In 1952, the American Cancer Society’s (ACS) medical director, Charles S. Cameron, MD, wrote an editorial to the New York Times complaining that most physicians were not willing to cooperate with his organization’s efforts to promote cancer checkups that included the Pap smear. Over time the Pap smear campaign became overwhelmingly successful, due in part to the efforts of the ACS, but also due to the momentum of the women’s movement and books like Our Bodies Ourselves, which promoted the annual Pap test. In 1960, only 30 percent of American women had ever had a Pap smear, and 40% had never even heard of it. By the mid-1970s, over 50% of women were having annual Pap smears, and by 1980 the figures had jumped to 80%. Over the same interval, deaths from cervical cancer declined by almost 70%. Today, there still are over 4,500 new cases of invasive cervical cancer diagnosed annually, with most of these occurring in women who have never had a Pap smear. Despite its success, there is actually very little science to support the choice of an annual screening interval for cervical cancer screening. This particular screening interval was adopted somewhat arbitrarily to mirror the rhythm of refilling annual birth control prescriptions, but it became an annual ritual for millions of American women. In 1976, the Canadian Walton Report challenged the annual screening interval by suggesting that cervical cancer screening every 3 years was as effective as annual screening and in 1980 a National Institutes of Health panel advocated that all women have a Pap smear every one to three years. By 1992, it was apparent that cervical cancer was causally related to the human papilloma virus (HPV) virus. Terminology for the interpretation of Pap smears was standardized in 2001, eliminating much confusion about the interpretation of smears; and by 2003 it became possible to detect the HPV virus from the Pap smear sample itself, enabling doctors to identify high-risk women. In 2003, both The ACS and the American College of Obstetrics and Gynecology changed their cervical cancer screening recommendations to take into account the biology of cervical cancer as well as the evidence that a longer screening interval was as effective as the annual smear for women who had previously had three consecutive negative smears. In 2006, the Food and Drug Administration licensed the first vaccine to prevent cervical cancer caused by certain strains of HPV. Now, with both the HPV vaccine and virus testing available, the possibility of reducing the interval for Pap smears even further has become a reality.