Surendra Srinivas Shastri, MD
A simple visual screening test using vinegar (acetic acid) has the potential to dramatically reduce the number of deaths from cervical cancer in the developing world, according to findings from a large, randomized study of 150,000 women in India, where use of the screening tool yielded a 31% reduction in cervical cancer mortality.
Researchers estimate that the strategy may prevent 22,000 cervical cancer deaths every year in India and nearly 72,000 such deaths in resource-poor countries around the world.
Announcing his team’s research findings June 1 at this year’s ASCO meeting in Chicago, lead study author Surendra Srinivas Shastri, MD, said that this trial is the “first to identify a cervical cancer screening strategy that reduces mortality and is feasible to implement on a broad scale throughout India and in other developing countries.” Shastri is professor of Preventive Oncology at Tata Memorial Hospital in Mumbai, India.
For the study, women aged 35 to 64 from 20 slum clusters in Mumbai, who had no previous history of cancer, were randomly assigned either to screening every 2 years (n = 75,360) using visual inspection with acetic acid (VIA) or no cervical cancer screening (n = 76,178)—the current local standard of care in India, where there is no countrywide Pap screening program because there is no infrastructure to support it, the researchers noted.
The screening group received four rounds of VIA screening and cancer education at 2-year intervals between 1998 and 2010 from primary health workers (PHWs). The control group was given one round of cancer education at recruitment and advised to report any signs of cervical cancer that they noticed to their PHW.
Shastri explained that the first challenge for researchers was to educate women about cervical cancer and the benefits of screening, because they had had no prior experience of such programs. “We had to pass through several layers of community barriers before we could actually talk to these women about cervical cancer screening and then start the screening process,” he said. This process involved talking with political and religious leaders, as well as teachers, who are very influential in these communities, Shastri added.
“This ensured a sense of community ownership,” he said, and yielded “very good participation.” A rate of 89% participation was achieved in the screening group, which Shastri described as “huge for a country like India and in most other places.” Participation in the control group was also high (91%).
The VIA test is performed by applying vinegar to the cervix using a cotton swab. After 60 seconds, the cervix is examined with the naked eye using a lamp. Precancerous tissue turns white when vinegar is applied; healthy tissue does not change color.
The PHWs who performed the screening were local women with at least a 10th grade education and good communication skills. They were given 4 weeks of intensive training at the beginning of the study plus 1-week refresher courses each year, and the quality of their screening proved to be comparable to that of an expert gynecologist (K = 0.84).
The incidence of invasive cervical cancer was 26.7% per 100,000 in the screening group and 27.5% in the control group. Treatment compliance when cervical cancer was diagnosed was 86.3% in the screening group and 72.3% in the control group. Most notably, a 31% reduction in cervical cancer mortality was seen in the screening group (95% CI, 0.54-0.88; P
Study authors pointed to the benefits of having PHWs conduct the screening and education program, both because they can easily access women in their communities, especially in remote and rural areas, and because of the overall lack of sufficient nurses, physicians, and laboratory facilities in India and other developing countries.
Shastri stressed that another important finding from this study is that there was no overdiagnosis. “Overdiagnosis is a huge problem in all screening programs and all screening trials. There was almost zero overdiagnosis in this trial,” he noted.