The Scientist Behind the Pap Smear Saved Countless Women from Cervical Cancer
For decades, women around the world have made the annual pilgrimage to their doctor for the dreaded but potentially life-saving Papanicolaou test, a gynecological exam to screen for cervical cancer named for Georgios Papanicolaou, the Greek immigrant who developed it.
The Pap smear, as it is commonly known, is credited for reducing cervical cancer mortality by 70% since the 1960s; the American Cancer Society (ACS) still ranks the Pap as the most successful screening test for preventing serious malignancies. Nonetheless, the agency, as well as other medical panels, including the US Preventive Services Task Force and the American College of Obstetrics and Gynecology are making a strong push to replace the Pap with the more sensitive high-risk HPV screening test for the human papillomavirus virus, which causes nearly all cases of cervical cancer.
So, how was the Pap developed and how did it become the gold standard of cervical cancer detection for more than 60 years?
Born on May 13, 1883, on the island of Euboea, Greece, Georgios Papanicolaou attended the University of Athens where he majored in music and the humanities before earning his medical degree in 1904 and PhD from the University of Munich six years later. In Europe, Papanicolaou was an assistant military surgeon during the Balkan War, a psychologist for an expedition of the Oceanographic Institute of Monaco and a caregiver for leprosy patients.
When he and his wife, Andromache Mavroyenous (Mary), arrived at Ellis Island on October 19, 1913, the young couple had scarcely more than the $250 minimum required to immigrate, spoke no English and had no job prospects. They worked a series of menial jobs--department store sales clerk, rug salesman, newspaper clerk, restaurant violinist--before Papanicolaou landed a position as an anatomy assistant at Cornell University and Mary was hired as his lab assistant, an arrangement that would last for the next 50 years.
Papanikolaou would later say the discovery "was one of the greatest thrills I ever experienced during my scientific career."
In his early research, Papanikolaou used guinea pigs to prove that gender is determined by the X and Y chromosomes. Using a pediatric nasal speculum, he collected and microscopically examined vaginal secretions of guinea pigs, which revealed distinct cell changes connected to the menstrual cycle. He moved on to study reproductive patterns in humans, beginning with his faithful wife, Mary, who not only endured his almost-daily cervical exams for decades, but also recruited friends as early research participants.
Writing in the medical journal Growth in 1920, the scientist outlined his theory that a microscopic smear of vaginal fluid could detect the presence of cancer cells in the uterus. Papanikolaou would later say the discovery "was one of the greatest thrills I ever experienced during my scientific career."
At this time, cervical cancer was the number one cancer killer of American women but physicians were skeptical of these new findings. They continued to rely on biopsy and curettage to diagnose and treat the disease until Papanicolaou's discovery was published in American Journal of Obstetrics and Gynecology. An inexpensive, easy-to-perform test that could detect cervical cancer, precancerous dysplasia and other cytological diseases was a sea change. Between 1975 and 2001, the cervical cancer rate was cut in half.
Papanicolaou became Emeritus Professor at Cornell University Medical College and received numerous awards, including the Albert Lasker Award for Clinical Medical Research and the Medal of Honor from the American Cancer Society. His image was featured on the Greek currency and the US Post Office issued a commemorative stamp in his honor. But international acclaim didn't lead to a more relaxed schedule. The researcher continued to work seven days a week and refused to take vacations.
After nearly 50 years, Papanicolaou left Cornell to head and develop the Cancer Institute of Miami. He died of a heart attack on February 19, 1962, just three months after his arrival. Mary continued to work in the renamed Papanicolaou Cancer Research Institute until her death 20 years later.
The annual pap smear was originally tied to renewing a birth control prescription. Canada began recommending Pap exams every three years in 1978. The United States followed suit in 2012, noting that it takes many years for cervical cancer to develop. In September 2020, the American Cancer Society recommended delaying the first gynecological pelvic exam until age 25 and replacing the Pap test completely with the more accurate human papillomavirus (HPV) test every five years as the technology becomes more widely available.
Not everyone agrees that it's time to do away with this proven screening method, though. The incidence rate of cervical cancer among Hispanic women is 28% higher than for white women, and Black women are more likely to die of cervical cancer than any other racial or ethnicities.
Whether the Pap is administered every year, every three years or not at all, Papanicolaou will always be known as the medical hero who saved countless women who would otherwise have succumbed to cervical cancer.
Podcast: A Nasal Spray COVID Booster Shot, With Dr. Akiko Iwasaki
The "Making Sense of Science" podcast features interviews with leading medical and scientific experts about the latest developments and the big ethical and societal questions they raise. This monthly podcast is hosted by journalist Kira Peikoff, founding editor of the award-winning science outlet Leaps.org.
Real-world data shows that protection against Covid-19 infection wanes a few months after two or three shots of mRNA vaccines (while protection against severe disease remains high). But what if there was another kind of booster that could shore up the immune response in your nose, the "door" to your body? Like bouncers at a club, a better prepared nasal defense system could stop the virus in its tracks -- mitigating illnesses as well as community spread. Dr. Akiko Iwasaki, an immunologist at Yale, is working on such a booster, with fantastic results recently reported in mice. In this episode, she shares the details of this important work.
Listen to episode
Kira Peikoff was the editor-in-chief of Leaps.org from 2017 to 2021. As a journalist, her work has appeared in The New York Times, Newsweek, Nautilus, Popular Mechanics, The New York Academy of Sciences, and other outlets. She is also the author of four suspense novels that explore controversial issues arising from scientific innovation: Living Proof, No Time to Die, Die Again Tomorrow, and Mother Knows Best. Peikoff holds a B.A. in Journalism from New York University and an M.S. in Bioethics from Columbia University. She lives in New Jersey with her husband and two young sons. Follow her on Twitter @KiraPeikoff.
Technology is Redefining the Age of 'Older Mothers'
In October 2021, a woman from Gujarat, India, stunned the world when it was revealed she had her first child through in vitro fertilization (IVF) at age 70. She had actually been preceded by a compatriot of hers who, two years before, gave birth to twins at the age of 73, again with the help of IVF treatment. The oldest known mother to conceive naturally lived in the UK; in 1997, Dawn Brooke conceived a son at age 59.
These women may seem extreme outliers, almost freaks of nature; in the US, for example, the average age of first-time mothers is 26. A few decades from now, though, the sight of 70-year-old first-time mothers may not even raise eyebrows, say futurists.
“We could absolutely have more 70-year-old mothers because we are learning how to regulate the aging process better,” says Andrew Hessel, a microbiologist and geneticist, who cowrote "The Genesis Machine," a book about “rewriting life in the age of synthetic biology,” with Amy Webb, the futurist who recently wondered why 70-year-old women shouldn’t give birth.
Technically, we're already doing this, says Hessel, pointing to a technique known as in vitro gametogenesis (IVG). IVG refers to turning adult cells into sperm or egg cells. “You can think of it as the upgrade to IVF,” Hessel says. These vanguard stem cell research technologies can take even skin cells and turn them into induced pluripotent stem cells (iPSCs), which are basically master cells capable of maturing into any human cell, be it kidney cells, liver cells, brain cells or gametes, aka eggs and sperm, says Henry T. “Hank” Greely, a Stanford law professor who specializes in ethical, legal, and social issues in biosciences.
Mothers over 70 will be a minor blip, statistically speaking, Greely predicts.
In 2016, Greely wrote "The End of Sex," a book in which he described the science of making gametes out of iPSCs in detail. Greely says science will indeed enable us to see 70-year-old new mums fraternize with mothers several decades younger at kindergartens in the (not far) future. And it won’t be that big of a deal.
“An awful lot of children all around the world have been raised by grandmothers for millennia. To have 70-year-olds and 30-year-olds mingling in maternal roles is not new,” he says. That said, he doubts that many women will want to have a baby in the eighth decade of their life, even if science allows it. “Having a baby and raising a child is hard work. Even if 1% of all mothers are over 65, they aren’t going to change the world,” Greely says. Mothers over 70 will be a minor blip, statistically speaking, he predicts. But one thing is certain: the technology is here.
And more technologies for the same purpose could be on the way. In March 2021, researchers from Monash University in Melbourne, Australia, published research in Nature, where they successfully reprogrammed skin cells into a three-dimensional cellular structure that was morphologically and molecularly similar to a human embryo–the iBlastoid. In compliance with Australian law and international guidelines referencing the “primitive streak rule," which bans the use of embryos older than 14 days in scientific research, Monash scientists stopped growing their iBlastoids in vitro on day 11.
“The research was both cutting-edge and controversial, because it essentially created a new human life, not for the purpose of a patient who's wanting to conceive, but for basic research,” says Lindsay Wu, a senior lecturer in the School of Medical Sciences at the University of New South Wales (UNSW), in Kensington, Australia. If you really want to make sure what you are breeding is an embryo, you need to let it develop into a viable baby. “This is the real proof in the pudding,'' says Wu, who runs UNSW’s Laboratory for Ageing Research. Then you get to a stage where you decide for ethical purposes you have to abort it. “Fiddling here a bit too much?” he asks. Wu believes there are other approaches to tackling declining fertility due to older age that are less morally troubling.
He is actually working on them. Why would it be that women, who are at peak physical health in almost every other regard, in their mid- to late- thirties, have problems conceiving, asked Wu and his team in a research paper published in 2020 in Cell Reports. The simple answer is the egg cell. An average girl in puberty has between 300,000 and 400,000 eggs, while at around age 37, the same woman has only 25,000 eggs left. Things only go downhill from there. So, what torments the egg cells?
The UNSW team found that the levels of key molecules called NAD+ precursors, which are essential to the metabolism and genome stability of egg cells, decline with age. The team proceeded to add these vitamin-like substances back into the drinking water of reproductively aged, infertile lab mice, which then had babies.
“It's an important proof of concept,” says Wu. He is investigating how safe it is to replicate the experiment with humans in two ongoing studies. The ultimate goal is to restore the quality of egg cells that are left in patients in their late 30s and early- to mid-40s, says Wu. He sees the goal of getting pregnant for this age group as less ethically troubling, compared to 70-year-olds.
But what is ethical, anyway? “It is a tricky word,” says Hessel. He differentiates between ethics, which represent a personal position and may, thus, be more transient, and morality, longer lasting principles embraced across society such as, “Thou shalt not kill.” Unprecedented advances often bring out fear and antagonism until time passes and they just become…ordinary. When IVF pioneer Landrum Shettles tried to perform IVF in 1973, the chairman of Columbia’s College of Physicians and Surgeons interdicted the procedure at the last moment. Almost all countries in the world have IVF clinics today, and the global IVF services market is clearly a growth industry.
Besides, you don’t have a baby at 70 by accident: you really want it, Greely and Hessel agree. And by that age, mothers may be wiser and more financially secure, Hessel says (though he is quick to add that even the pregnancy of his own wife, who had her child at 40, was a high-risk one).
As a research question, figuring out whether older mothers are better than younger ones and vice-versa entails too many confounding variables, says Greely. And why should we focus on who’s the better mother anyway? “We've had 70-year-old and 80-year-old fathers forever–why should people have that much trouble getting used to mothers doing the same?” Greely wonders. For some women having a child at an old(er) age would be comforting; maybe that’s what matters.
And the technology to enable older women to have children is already here or coming very soon. That, perhaps, matters even more. Researchers have already created mice–and their offspring–entirely from scratch in the lab. “Doing this to produce human eggs is similar," says Hessel. "It is harder to collect tissues, and the inducing cocktails are different, but steady advances are being made." He predicts that the demand for fertility treatments will keep financing research and development in the area. He says that big leaps will be made if ethical concerns don’t block them: it is not far-fetched to believe that the first baby produced from lab-grown eggs will be born within the next decade.
In an op-ed in 2020 with Stat, Greely argued that we’ve already overcome the technical barrier for human cloning, but no one's really talking about it. Likewise, scientists are also working on enabling 70-year-old women to have babies, says Hessel, but most commentators are keeping really quiet about it. At least so far.