Smartphones, Vinegar and the Future of Cervical Cancer Screening

100 years ago, cervical cancer reigned as the leading cause of cancer death for women in the United States

Then, a doctor at Cornell University began conducting studies on the sex cycle of guinea pigs and in 1915 realized that a similar “smear” technique could be applied to the study of human vaginal cells. A few decades of disinterest and skepticism later, the Pap smear became the standard cancer screening test for women. Today, the cervical cancer death rate has plunged by more than 50 percent and ranks 14th in frequency in the United States.

This is far from the case in developing countries, where cervical cancer is the most common cancer and the leading cause of cancer deaths among women. Over 85 percent of cervical cancer cases occur in the developing world and these staggering rates are largely due to the lack of screening. Pap smears are rare and less than five percent of women receive any cervical cancer screening at all.

However, new research and innovations in cervical cancer screening are helping to increase its breadth and frequency in many of the world’s poorest countries. Moreover, these new approaches are actually more accurate, convenient, and cost-effective than the traditional Pap smear, not to mention less unpleasant. They let doctors and their patients bypass the Pap smear altogether, while the Pap smear’s dominance in the U.S. remains strong.

No Place for the Pap

Many women may be surprised to learn that the Pap smear only detects cancer about half of the time but repeating the test on a regular basis increases the chances of finding cancer since the disease is slow to develop.

Repeating the test regularly is often not an option in developing countries where a number of barriers -- time, money, distance, transportation, children, agricultural cycles, social stigmas -- prevent women from visiting health clinics. Paps also take a hefty amount of resources to administer and read.

“The Pap test is hard to implement in low resource settings because it requires expensive machines, labs, and trained technicians, as well as for women to make the trips to clinics,” said Dr. José Jerónimo, the senior adviser for women’s cancers in a reproductive health program called PATH.

PATH is an international nonprofit dedicated to accelerating health innovation in the developing world. The organization has a number of initiatives aimed at making cervical cancer screening and prevention more prevalent in under-resourced areas. A key part of its approach is a low-tech effort called “VIA”, which stands for visual inspection with acetic acid.

This method involves swabbing the cervix with a 3 to 5 percent vinegar solution during a speculum exam, waiting for one minute, and then observing the cervix to see if white areas appear. In addition to being inexpensive and easy to administer, VIA also provides immediate results. It allows a patient to immediately receive guidance on next steps if the test is positive.

However, like the Pap, the vinegar technique only identifies 50 to 60 percent of precancerous cases, which is why PATH helped develop a new molecular test called careHPV that was developed and field tested for use in low-resource settings.

CareHPV can detect DNA from 14 cancer-causing types of HPV in 2.5 hours without extensive lab facilities, using an affordable machine the size of a toaster oven that runs on electricity or a battery. Women can collect their own samples using a small brush, without the need for a pelvic exam.

This approach is ideal for environments where health care resources are limited and testing is often administered by community health workers who visit people’s homes, as well as in places where stigmas against pelvic exams persist.

Dr. Jerónimo said that simply by allowing women to collect the sample themselves, coverage increases by 4 times.

Texting, Calling, and Cervical Cancer Screening

MobileODT is a startup that makes a mobile colposcope, a long-range, Internet-connected magnifying glass that plugs into smartphones. The device provides a high-resolution image of cervical tissue, which can then be securely transmitted for diagnostics.

[Skip to the bottom to a video of how a mobile colposcope works.]

“There are very few labs or specialists in developing countries who are able to correctly assess cervical cancer at its early stages,” said MobileODT chief executive and cofounder Ariel Beery.

“What we seek to do is enable those same health workers who are already in the field to use a tool they use everyday — a mobile phone — to better visualize the cervix and collaborate with experts to process those images with greater accuracy.”

The advanced prototype of the mobile colposcope is currently being piloted in Kenya, Haiti, Mexico, Botswana and the U.S.. The startup ultimately hopes to use the data it collects to develop algorithms that are able to assess the risk of cervical cancer at any stage of the viruses’ development.

TeamLiveLonger is another startup leveraging smartphone technology to combat cervical cancer, although its goal is to increase the feasibility of Pap smears, rather than replace them.

Founder Lou Auguste is of Haitian descent and worked as a first responder after the 2010 earthquake. There, he learned that Haitian women have the highest rate of mortality from cervical cancer in the world, with 54 per 100,000 women dying from the disease each year.

“Most women in Haiti have never been tested for cervical cancer or they don’t catch it before it is too late,” Auguste said.

“Doctors know how to perform pap smears but we realized there were only 5 pathologists in the whole country, so we needed to figure out a system for sending slides for consultations abroad.”

TeamLiveLonger developed an adaptor that connects a smartphone to a microscope to acquire images of slides. Its mobile technology then stitches the images together to produce a whole slide and securely transfers the images via a service called BitTorrent Sync (which enables the app to transfer large files over bad Internet connections) to a pathologist in the U.S. for analysis and diagnosis. TeamLiveLonger also built an electronic health record for mobile devices that makes it easy for health workers to keep cases updated and know when people come back to the clinic to receive results or treatment.

The Pap smear may not be the best method of screening for cervical cancer but it does hold the dubious distinction of being the most prevalent one. Innovation after innovation has emerged in this space over the past 20 years but their adoption is much faster in the developing world without the entrenched legacy of the Pap smear to overcome.

While women in Haiti, India, Nicaragua and Uganda get screened for cervical cancer with a brush and a mobile phone, it looks like women in the U.S. will have to endure the speculum for the foreseeable future.