Mumbai: Findings from a randomized, controlled trial conducted by doctors at the Tata Memorial Hospital among 150,000 women in Mumbai slums over a 15-year period show that biennial screening for cervical cancer — the most common and most deadly cancer among Indian women — by trained non-medical personnel using acetic acid (vinegar) reduced cervical cancer mortality by 31 per cent.
If implemented in developing countries that have little or no access to Pap screening, this easy-to-use procedure could ultimately prevent 22,000 deaths from cervical cancer in India and 72,000 deaths in low-resource countries worldwide each year, according to Dr Surendra S Shastri of the Tata Memorial Hospital.
The burden of cervical cancer weighs heavily in resource-limited settings, largely a result of lack of screening programmes. Nearly 142,000 cases of cervical cancer occur each year in India alone, and annually more than 77,000 Indian women die of the disease. When viewed from a global perspective, these figures account for approximately 30 per cent of the burden of cervical cancer worldwide.
Whereas Pap smear screening for precancerous cells has cut cervical cancer incidence and mortality by 80 per cent in high-income countries, large-scale Pap screening is simply not feasible in India. In 1992 and again in 2006, the government determined that inadequate infrastructure, lack of trained personnel, logistic difficulties, and the relatively high cost of the procedure pose too great a drain on restricted resources.
VIA (visual inspection with acetic acid) is a simple, rapid, inexpensive test that offers a practical alternative to Pap smears or HPV DNA testing in resource-limited settings. Sixty seconds after applying vinegar to the cervix using a cotton swab, precancerous lesions turn white and can be discerned from pink healthy tissue with the naked eye—something that primary health workers can easily be trained to identify with high accuracy.
Given these advantages, “VIA is a technique that can be used in the lowest-resource settings in countries like India,” Dr Shastri said on Tuesday at the annual meeting of the American Society of Clinical Oncology held in Chicago.
Dr Shastri and colleagues sought to evaluate the feasibility of using VIA as a large-scale screening programme for reducing cervical cancer mortality in India. The investigators initiated a randomized controlled trial in 1998 among 151,538 women age 35 to 64 in Mumbai slums who had no prior cancer history. One-half of the women were randomly assigned to receive four rounds of cancer education and VIA every 24 months, whereas the other one-half received no screening — the current standard of care in India — and one-time cancer education at recruitment.
All women in the screening group who tested positive by VIA, and those in the control group who noticed signs or symptoms of cervical cancer taught to them at enrolment, were directed to Tata Memorial Hospital or other facilities for diagnosis. Those with confirmed disease received free cervical cancer treatment.
Invasive cervical cancer occurred at a similar incidence in the screening and control groups (26.74 and 27.49 cases per 100,000 women-years of observation, respectively), demonstrating no overdiagnosis from screening. “This is a crucial factor in low-resource settings where the public health systems are already overburdened,” Dr Shastri emphasized.
VIA enabled diagnosis at an earlier stage of the disease and hence earlier treatment, which translated into survival gains. Use of VIA significantly reduced the rate of cervical cancer mortality from 16.22 to 11.12 deaths per 100,000 women-years of observation (p = 0.003) — a 31 per cent reduction compared with the control group. All-cause mortality also fell by 7 per cent in the screening group compared with the control group, from a rate of 873.01 to 814.51 deaths per 100,000 women-years of observation, although this change was not statistically significant (p = 0.406).
Instead of having to rely on physicians and nurses, the screening exams were carried out by primary health workers trained to perform VIA in only 4 weeks. These were local women with at least a 10th-grade education and good communication skills. Dr Shastri noted that an expert gynaecologist randomly rescreened approximately 5 per cent of participants using the VIA technique, confirming excellent agreement with the findings of the trained nonmedical personnel (kappa = 0.84).
Although study follow-up is still ongoing, Dr Shastri has immediate plans to begin to implement VIA screening more broadly. “We are already working with state and national health authorities in India to make this screening strategy available to women throughout the country,” Dr Shastri told ASCO Daily News.