A successful cervical cancer screening experiment in rural Thailand has shown that developing countries can combat a leading women's health threat cheaply with limited technology.
Cervical cancer is the world's main cause of female cancer deaths, killing nearly 300,000 women annually.
Thai and U.S. public health experts say a simple vinegar test combined with immediate treatment in a single visit offers hope for fighting this scourge in poor parts of the world.
Johns Hopkins University gynecologist Paul Blumenthal helped design the project. "What's attractive about our approach is that almost all the components necessary to run the entire program are available locally," he said.
In industrial countries, the Pap smear is the common tool to assess a woman's risk of cervical cancer. It requires sophisticated laboratories and highly trained technicians. Women usually must make three visits and many do not complete the process.
But Dr. Blumenthal's Johns Hopkins team and doctors from the Royal Thai College of Obstetrics and Gynecology combined an inexpensive vinegar wash test and a simple visual inspection to do the same thing in a single visit. The vinegar solution bleaches abnormal cells, which become visible to the naked eye.
Studies have found the process can identify most cases of pre-cancer and cancer as well as a Pap smear can.
In the Thai experiment, women shown to have abnormal cells underwent immediate cryotherapy, a freezing process that destroys affected tissue. Cryotherapy units have few moving parts and do not use electricity, but instead rely on carbon dioxide coolant in tanks. "We showed that this scenario was safe and acceptable and therefore likely to be feasible," said Dr. Blumenthal.
The researchers report in the medical journal The Lancet that local nurses screened 6,000 rural Thai women aged 30 to 45 with the vinegar wash. Thirteen percent tested positive for precancerous cells and almost all of them agreed to immediate cryotherapy. The intervention worked for the vast majority who received the treatment. Dr. Blumenthal says that 94 percent tested negative when screened a year later. "Whether or not we have reduced mortality from cervical cancer will take a while to determine that factually," he said. "Those patients may not have been destined to get cervical cancer for five or even 10 years. But intuitively, if we can prevent the precursor, then it makes sense that we will have prevented the disease."
The Johns Hopkins gynecologist says the test project in Thailand is important for policymakers and public health experts in developing countries, who are considering the best way to begin or strengthen cervical cancer prevention programs. "There is tremendous interest in these alternative approaches to cervical cancer around the world," he said. "This is another example where a gram of prevention is worth a kilo[gram] of cure."