In the U.S., the pap smear has become a routine part of women's health care, and it's dramatically reduced cervical cancer deaths. But in Africa and other impoverished regions, few women get pap smears because the countries lack the laboratories and other resources necessary to offer them.
The World Health Organization reports that more than 80 percent of deaths from cervical cancer now occur in low-income nations. Thus, there's a push to come up with a new, low-tech way to screen women for cervical cancer in the developing world.
Now doctors think a bit of vinegar may be a solution.
"We have already seen that the pap smear hasn't worked as a public health intervention for preventing cervical cancer in low and middle-income countries," Ricky Lu, an obstetrician-gynecologist with the international health group Jhpiego, which is associated with Johns Hopkins University.
Lu is promoting a cervical cancer screening technique in which a nurse or a midwife simply swabs a woman's cervix with vinegar (or diluted acetic acid) and then looks with the naked eye, or a magnifying glass, for pre-cancerous lesions. The screening technique requires only vaginal spoons, vinegar and a bit of training. It can be performed in the simplest health clinics without a need for laboratory tests or even electricity.
In the developing world, Lu says, public health providers need a cervical cancer screening tool that is fast, easy and inexpensive. "We need a test that is simple, practical and good enough to identify precancerous lesions," he says. "And then also it's critical that it is available where women come [for health care]."
When a health care provider spots a precancerous lesion with the vinegar test, it can often be removed immediately, and the entire procedure takes only a few minutes.
At least six countries in Africa have now adopted the technique as part of their public health care systems, and it's also caught on in Thailand and parts of Asia.
Doreen Ramogola-Masire, an obstetrician-gynecologist in Botswana, is using a similar approach. One of the key elements of the technique, she says, is that women can be tested and treated in a single visit.
Ramogola-Masire simply swabs a woman's cervix with vinegar and then looks for any potentially cancerous lesions, which appear as white tissue. If pre-cancerous lesions are present, she freezes them with nitrous oxide.
"She's lying on the couch," Ramogola-Masire says. "You look at [the cervix], you wash it with vinegar. You take a picture. You can immediately review the picture because you've got a screen. So you can say to them, this is the white change. I think this is where the abnormality is. We are going to freeze it. What happens is the freezing actually takes care of the top layer. You just sluff that off. And hopefully you've taken care of the problem."
Almost all cervical cancer is caused by the human papillomavirus. There appears to be higher rates of HPV and cervical cancer among women with HIV, Ramogola-Masire says. Botswana has one of the highest rates of HIV in the world, with nearly a quarter of all adults believed to be HIV positive.
In the early days of the AIDS epidemic, Ramogola-Masire says, cervical cancer wasn't much of a concern because women with HIV weren't living long enough for the cancer to develop. Once cervical cancer has spread, it's difficult to treat, particularly in poor countries with limited health resources.
If caught early, cervical cancer is easily treatable. If not, Ramogola-Masire says, it's a terrible death. "It invades you nerves at the spine at the back, so you are in a lot of pain," she says.
"The other thing is that because there's a lot of dead tissue, you smell. There's a lot of bleeding. You're incontinent. You're in pain, you're bleeding ... I think it's just a horrible disease to die from."
Ramogola-Masire hopes that the widespread adoption of cervical cancer screening with vinegar in the developing world can help prevent those horrible deaths.
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Deaths from cervical cancer in the U.S. and other developed countries declined dramatically over the latter half of the 20th century. That's partly because pap smears have become a routine part of women's health checkups. But in the developing world they're not routine and women continue to die from the highly treatable form of cancer. According to the World Health Organization, roughly 80 percent of cervical cancer deaths now occur in low income countries. NPR's Jason Beaubien reports now on a growing push for the low-tech alternative to pap smears, one that uses little more than household vinegar.
JASON BEAUBIEN, BYLINE: In Botswana at a small clinic behind the Princess Marina Hospital in the capital, Dr. Doreen Ramogola-Masire is in a rush. Matronly women in their 30s and 40s are sitting on long benches in the clinic's central corridor waiting to be screened for cervical cancer. Ramogola-Masire clicks through photos on a Motorola cell phone.
DR. DOREEN RAMOGOLA-MASIRE: This is normal cervix. It's nice pink.
BEAUBIEN: But then on the later image on the phone there's a cloudy white area on a cervix.
RAMOGOLA-MASIRE: And that is abnormality we're talking about. So this is quite thick. So to me that will be a moderate, severe abnormality.
BEAUBIEN: That abnormality is tissue that may eventually turn into cervical cancer and if it does, Ramogola-Masire says, it will probably be fatal. Across Africa, most women are never screened for cervical cancer. Pap smears require tissue samples to be analyzed in a lab. The results then have to get shipped back to clinics where they may or may not ever reach the original patient. Even testing for HPV which causes most cases of cervical cancer is difficult in places where women only sporadically access health care. Ramogola-Masire in Botswana is using a much simpler approach.
RAMOGOLA-MASIRE: One visit. Same visit.
BEAUBIEN: Ramogola-Masire simply swabs a woman's cervix with vinegar and then looks to see if any potentially cancerous abnormalities have turned white. If pre-cancerous lesions are present, she freezes them off with nitrous oxide.
RAMOGOLA-MASIRE: She's lying on the couch, you look at it, you wash it with vinegar. You take a picture. You can immediately review the picture because you've got a screen, so you can say to them, this is the white change and I think this is where the abnormality is. We are going to freeze it and what happens, the freezing actually takes care of the top layer, it just sluffs(ph) that off. And hopefully, you've taken care of the problem.
BEAUBIEN: The picture can even be taken with a cell phone and sent to a doctor for review. Although on this day, Ramogola-Masire is using a digital camera. The entire process can be done by a trained mid-wife and take only a few minutes. If the patient already has developed cancer, this vinegar test will show that, but the treatment is far more complex. At least six countries in Africa have started using the vinegar screening technique in government health clinics. It's also caught on in Thailand and several other Asian countries. Ricky Lu with the global health group, Jhpiego from Johns Hopkins University, has been studying the technique as alternative to pap smears for more than a decade.
DR. RICKY LU: We have already seen that the pap smear hasn't worked as a public health intervention for preventing cervical cancer in low and middle income countries.
BEAUBIEN: Dr. Lu has a slightly different procedure from Dr. Ramogola-Masire in Botswana. Rather than using nitrous oxide to freeze any abnormal lesions, Jhpeigo is using carbon dioxide or dry ice. This, Dr. Lu says, is because carbon dioxide is more widely available.
LU: Dry ice or carbon dioxide is always going to be available where you would probably find Coca-Cola or Pepsi bottling companies because they run their soda companies using carbon dioxide as well. So there must be some source of carbon dioxide somewhere.
BEAUBIEN: The dry ice or the nitrous oxide is delivered to the tip of the cervix with a wand that costs about $2,000. This is the most expensive part of the procedure. Jhpiego is trying to come up with a cheaper alternative.
MARTIN VARADY: Basically, all you have to do is turn it on for about 10 seconds.
BEAUBIEN: Martin Varady with Jhpiego just got his masters in bio-medical engineering from Johns Hopkins. He's holding a prototype of a dry ice delivery system that uses a compact 5-pound CO2 gas canister.
VARADY: Currently with the existing devices they usually get about 10 to 15 patients on a big 50-pound tank, but with this one, this is just the small 5-pound tank, we expect that we should be able to treat about 25 to 30 women.
BEAUBIEN: This new system, which they're still refining, could cost just a couple of hundred dollars, fit in a backpack and allow potentially life-saving cervical cancer screening in even the most remote parts of the world. Jason Beaubien, NPR News.
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