University of Pennsylvania Cancer Center
Last Modified: May 16, 1999
After an intense lobbying effort, the federal government agreed in 1990 to fund Pap smear tests for elderly recipients of Medicare. Now, researchers conclude that the tests have remarkably reduced the rate of invasive cervical cancer for at-risk women.
Dr. Fredrick Montz, of Johns Hopkins Hospital and Medical Institution, and other researchers studied data from the California Cancer Registry, which keeps comprehensive oncology records, to see if federal funding of Pap tests had resulted in a positive impact. They examined data from the three years before the change in funding (1998, '89, '90) and compared that data for the five years following the change (1991-1995), compiling the number of cases of in situ, or noninvasive, cervical cancer detected versus the number of invasive cancers diagnosed.
A Pap smear, ideally, finds evidence of cervical cancer before it has become invasive so if more women were receiving Pap smears, the number of invasive versus non-invasive cancer should fall. In fact, the researchers found that this ratio went down by about one-third in women over the age of 65 while decreasing to a significantly lesser degree for younger patients, and for all ages taken as a whole. In the older women, the ratio shifted from an average of 1.5 to 1.1. When older women were divided by ethnic group, it was evident that all races appeared to benefit by the change, though Whites and Asian/Pacific Islanders had the maximal benefit. Looked at in a different way, in the three years prior to the change in funding, 21 out of every 100,000 women in California over the age of 65 were found to have invasive cervical cancer and 14 women were identified as having in situ cancer. In the years 1991-95 -- after Medicare started to pay for Pap smears for older women -- more women (17) were found to have non-invasive cancer, and fewer (18) invasive cancers were detected.